WO2010012123A1 - A method for uplink/downlink logic topology structure management in a mesh network and the apparatus thereof - Google Patents

Abstract

A method for uplink/downlink logic topology management in a mesh network and the apparatus thereof are provided for solving problems in the prior art. Specifically, each first type of network device firstly determines whether a predetermined condition is satisfied, and when the predetermined condition is satisfied, based on the antenna array or one or more directional antennas installed thereon, it determines a new uplink logic connection originated from the first type of network device, wherein the new uplink logic connection points to a new uplink potential opposite terminal differing from the current uplink potential opposite terminal. The scheme can make that the opportunistic communication OC is still used when the gain of a wireless channel in the mesh network has no time-varying character or has worse time-varying character, and that the throughput in the mesh network can obtain greater improvement.

Description

 Upstream and downstream logic in mesh networks

 Method and device for topology management

 The present invention relates to mesh networks, and more particularly to methods and apparatus for managing uplink and downlink logical topology structures in a mesh network. Background technique

 The development of modern communication theory in recent years reveals the fact that the time variation of the wireless channel is beneficial to increase the throughput of the system, for example, the number of bits transmitted per Hz per second is bps/HZ.

 With the support of the above theory, a unique communication technology emerged, namely Opportunistic Communication (hereinafter referred to as OC). The basic idea is that the signal is transmitted when the channel gain is high, and the signal is not transmitted when the channel gain is low. The gain of the static channel is a Rayleigh random variable, but it does not change with time. The gain of the time-varying channel is also a Rayleigh random variable, but with time, a lot of practice proves that when the channel condition has good time-varying , can achieve greater throughput than non-time-varying channel conditions. Figure 1 shows the communication between a transmitting end and a receiving end over a period of time. The channel gain changes significantly with time. When the channel gain exceeds a predetermined channel gain threshold, that is, corresponding to the shaded area. Within the time range, the transmitting end will try to send a signal to the receiving end, and when the channel gain falls below the threshold, the above signal transmission will be aborted, the transmitting end enters a silent state, and the data to be transmitted generated by itself is generated. Cache is performed, waiting for channel conditions to become advantageous again.

 In order to take full advantage of the throughput advantages brought by the change of the wireless channel, there are three solutions in the prior art:

 1. The most basic OC in a star network

 See David Tse & Stephen Hanly, <Multi-Access Fading Channels: Part I: Polymatroid Structure, Optimal Resource Allocation and Throughput Capacities^, IEEE Transactions on Information Theory, v. 44(7), Nov., 1998.

 1

Confirmation This document provides a detailed description of the most basic OC in a star network. A typical star network is a wireless access network composed of a mobile terminal and a base station (or Node B) as shown in FIG. 2. Taking the uplink as an example, based on the estimation result of the uplink channel between each mobile terminal and the base station, the base station only selects to receive the mobile station whose uplink channel gain is higher than a predetermined threshold value in any period of time. The signal sent by the terminal, in particular, the base station can allocate all the corresponding time-frequency resources to those mobile terminals with higher uplink channel gain between the base stations. In FIG. 2, the mobile terminal and the base station are connected by a solid line, that is, the mobile terminal can send a signal to the base station at this time. Conversely, the mobile terminal and the base station are connected by a dotted line to indicate that the mobile terminal cannot send a signal to the base station at this time. Or, even if it sends a signal, it will not be accepted by the base station.

 2. Opportunistic communication based on beamforming in a star network,

 Opportunistic Beam Forming based on beamforming in a star network is also referred to as Opportunistic Beam Forming. Referring to Figure 3, in the star network shown therein, the mobile terminal is stationary, and thus, when it is connected to the base station When the scatterer (eg, car, house, etc.) does not move for a period of time, the channel gain versus time between the mobile terminal and the base station will be a horizontal straight line. However, if the mobile terminal moves slowly, in the field of wireless communication, the slow moving is typically the speed when the person walks, and the channel between the base station and the base station will be in a slow fading state, and it is also difficult to achieve opportunistic communication for the channel condition. The ideal requirement shown in Figure 1.

 It can be seen that the most basic OC in a star network is only suitable for the case where the mobile terminal moves quickly, causing a rapid change in channel gain, or a channel that naturally changes rapidly. to this end,

Pramod Viswanath & David Tse, Opportunistic Beam forming using Dumb Antennas>, IEEE Transactions on Information Theory, vol. 48(6), June, 2002, proposing a conventional antenna array consisting of multiple transmit antennas for a transmitter (Conventional Antenna Array ), and control the direction of the beam (Beam) finally obtained by multiple transmitting antennas by complex weighting the modulation symbols on different transmitting antennas. Therefore, when the weighting coefficients used are constantly changing, multiple transmitting antennas are used. The beam formed on the antenna will rotate 360 degrees around the transmitting end. Therefore, the channel condition between the receiver and the receiving end will have a strong time-varying, thus artificially creating opportunistic communication in the star network. The condition of the letter.

 3. Existing opportunistic communications in mesh networks

 Although people have conducted in-depth research on opportunistic communication in a star network, opportunistic communication in mesh networks is not mature enough. See Ma & Qian Zhang & Chen Qian & Lionel M. Ni, <Energy-efficient opportunistic topology control in wireless sensor networh>, in the First International Workshop on Mobile Opportunistic Networking- (MobiOpp) in conjunction with ACM Mobisys, 07, where The idea of implementing opportunistic communication in the sensor network shown in Figures 4a-4b,

 In the sensor network shown in Figures 4a, 4b, network devices 1-7 are wireless sensors that are responsible for collecting data and transmitting it wirelessly to network devices 8, 9. The functions of the network devices 8, 9 are similar to those of the wireless gateway, for receiving wireless signals from various sensors, and transmitting them to a server or the like via a wired link, so as to analyze and process the collected data. Hereinafter, a network device similar to 8, 9 in a mesh network is referred to as a hub device, and a network device similar to the sensor 1-7 that directly or indirectly communicates with the hub device is referred to as a node. . In addition, the network devices herein generally refer to various devices appearing in the mesh network, including but not limited to the above-mentioned nodes and hub devices.

 In the sensor network shown in Figures 4a and 4b, each node and hub device use an omnidirectional antenna for signal transmission.

 According to one characteristic of the mesh network, many of the nodes cannot communicate directly with the hub device. A typical cause of this phenomenon is that the physical distance between these nodes and the pivot device is very far. To this end, in the mesh network, the nodes that cannot directly communicate with the hub device, such as the nodes 1, 2, etc. shown in Figure 4a, are often relayed by other nodes. Similarly, when the hub device reaches a certain When the downlink quality of each node is too far due to the distance, the data sent by the hub device to the corresponding node will also be relayed by other nodes.

As shown in FIG. 4a, since the node 4 is closer to the hub device 8, the uplink channel quality is extremely poor, so that the channel attenuation of the uplink channel of the node 4 hub device 8 is greater than that of the node 4^ node 6~ hub. The sum of the attenuations on this channel of device 8. Therefore, when determining the uplink logical topology, the uplink logical topology of this time period does not include the node 4 hub. Device 8 is an upstream logical connection. The uplink signal sent by node 4 is forwarded by node 6. In addition, the link between nodes 1 and 3 is also extremely poor, so node 1 is only connected to node 4,

There is a logical connection between 2, and when the routing of the uplink signal is performed, the signal sent by node 1 finally reaches the hub device 9 via nodes 2, 5. This routing result may be determined by the following conditions:

 - There are certain principles for routing, such as: less hop count, lower link attenuation, etc.

 - The path of node 1 to node 1 or 2 includes the following:

 1-2-5-Bridge equipment 9; 1-2-3-6-Bridge equipment 9; 1-4-6-Bridge equipment 9; 1-4-6- Hub equipment 8; 1-2-3-6- Hub device 9;

 - Consider the principle of less hops, and eliminate 1-2-3-6-hub equipment 8 and 1-2-3-6- hub equipment with more hops 9;

 - Considering the principle of low link attenuation, since the total attenuation of the link 1-2-5-the hub device 9 is the lowest, the uplink route is finally selected for the node 1.

 After a period of time, the channel conditions between the nodes change due to the relative displacement between the nodes or other reasons. At this time, the channel quality on the uplink logical connections of nodes 1 to 3 is good, and thus, the uplink network logic extension The Park structure becomes as shown on the right. In addition, the principle of less hop count and lower link attenuation is considered. Finally, the 1-3-6-hub device 8 with 3 hops and the total link attenuation is selected as the uplink route of node 1.

 The scheme shown in the above figure is also applicable to the case where there is a relatively fast motion between nodes and a channel change occurs. At this time, the logic topology will adapt adaptively with this relative motion. The principle is similar to the foregoing, and will not be described again. .

 However, the OC in the existing sensor network has a disadvantage, that is, it relies too much on the natural variation of the channel, and causes the natural change of the channel, including but not limited to: movement between the transmitting end or the receiving end, and between the transmitting end and the receiving end. The scatterer moves or changes.

 Therefore, when the wireless channel between nodes and between the node and the hub device is not time-varying or time-varying, the OC scheme described above in connection with Figures 4a, 4b will no longer be applicable.

To this end, there is an urgent need for a new technical solution for use in a mesh network to implement OC under non-time-varying or time-varying channel conditions. Summary of the invention

 In order to solve the above problems in the prior art, an object of the present invention is to provide a technical solution applied to a mesh network, which should enable the gain of the wireless channel in the mesh network to be time-varying or less time-varying. Can still use oc.

 In order to achieve the above object, according to a first aspect of the present invention, a method for managing uplink logical topology structure in a mesh network is provided, where the mesh network includes a plurality of first type network devices, Each of the plurality of transmit antennas of the first type of network device respectively constitutes an antenna array, and the method includes the following steps: one or more of the first type of network devices satisfying a predetermined condition change corresponding to multiple transmit antennas of the first type The uplink space division encodes a parameter group, thereby changing the uplink logical topology of the mesh network.

 According to a second aspect of the present invention, a method for downlink logical topology management in a mesh network is provided, wherein the mesh network includes a plurality of first type network devices, each of the first The plurality of transmitting antennas of the type network device respectively form an antenna array, and the method comprises the following steps: one or more of the first type network devices satisfying a predetermined condition change a downlink space coding parameter corresponding to the plurality of transmitting antennas thereof Group, thereby changing the downlink logical topology of the mesh network.

 According to a third aspect of the present invention, an uplink topology management apparatus for uplink logical topology management in a first type of network device of a mesh network is provided, wherein the first type of network device is The root transmitting antennas form an antenna array, and the uplink topology management device includes: a first determining device, configured to determine whether the predetermined condition is met; and a first executing device, configured to be different from the current uplink when the predetermined condition is met The uplink space division coding parameter group of the space division coding parameter group is used as a new uplink space division coding parameter group corresponding to the plurality of transmission antennas, thereby changing an uplink logical topology structure of the mesh network; wherein, the new uplink The space division coding parameter set corresponds to an uplink logical connection of the first type of network device to one of the other network devices in its vicinity.

According to a fourth aspect of the present invention, a downlink topology management apparatus for downlink logical topology management in a first type of network device of a mesh network is provided, wherein the first type of network device is The transmitting antennas constitute an antenna array, and the downlink topology management device includes: a second determining device, configured to determine whether the predetermined condition is satisfied; And configured to, when the predetermined condition is satisfied, use a downlink spatial coding parameter group different from its current uplink spatial coding parameter group as a new downlink spatial coding parameter group corresponding to the multiple transmit antennas, thereby changing the The downlink logical topology structure of the mesh network; wherein the new downlink space division coding parameter group corresponds to a downlink logical connection of the first type network device to one of the other network devices in the vicinity thereof.

 With the present invention, technical effects including, but not limited to, the following can be obtained:

 - Can still be used when the channel gain of the mesh network is time-varying or time-varying

OC;

 - Make the throughput in the wireless communication system can be greatly improved;

 - Reduce the power consumption of network devices;

 - Provide multi-user diversity; '

 - By using the principle of minimum hop count, it can help to reduce the transmission delay. DRAWINGS

 Other features, objects, and advantages of the present invention will become more apparent from the Detailed Description of Description

 Figure 1 shows the communication between a transmitting end and the receiving end over a period of time; Figure 2 shows a wireless access network consisting of a mobile terminal and a base station (or Node B);

 Figure 3 shows a star network implementing beam-forming opportunistic communication; Figures 4a-4b show a mesh sensor network implementing opportunistic communication;

 Figure 5a shows a static uplink logical topology in a mesh network; Figure 5b shows signal transmission in a first time slot according to the uplink logical topology shown in Figure 5a;

 Figure 5c shows the signal transmission in the second time slot according to the uplink logical topology shown in Figure 5b;

 6a is a schematic diagram showing a dynamically adjustable mesh network uplink logical topology in a first time slot according to an embodiment of the present invention;

Figure 6b shows a dynamically adjustable mesh in accordance with an embodiment of the present invention. Schematic diagram of the network uplink logic topology in the second time slot;

 Figure 6c shows the signal transmission in the first time slot according to the uplink logical topology shown in Figure 6a;

 Figure 6d shows the signal transmission in the second time slot according to the uplink logical topology shown in Figure 6b;

 7 is a flow chart showing a method for uplink logical topology management in a network device of a mesh network according to an embodiment of the present invention;

 FIG. 8 is a block diagram showing an uplink topology management apparatus for uplink logical topology management in a network device of a mesh network according to an embodiment of the present invention; FIG.

 FIG. 9 is a block diagram showing a downlink topology management apparatus for downlink logical topology management in a network device of a mesh network according to an embodiment of the present invention; FIG.

 Figures 10a-10f show the results of simulating the invention under beamforming.

 Wherein, the same or similar reference numerals denote the same or similar step features or device (module) features. detailed description

 The invention is further described in detail below with reference to the accompanying drawings. Before introducing a specific flowchart of the method or apparatus of the method of the present invention, first compare the difference in network throughput caused by the static logic topology structure and the dynamic logic topology structure in the mesh network. It will be very helpful to make an intuitive and intuitive understanding of the present invention. In addition, in view of the fact that the present invention is fully applicable to the uplink and downlink logic topologies, the above will be mainly applied to the case where the present invention is applied to the downlink without any inventive effort, especially for symmetric channels.

 For simplicity of explanation, the following comparison is based on the following premise:

 - All nodes and hub devices use the same frequency resources;

 - All nodes and hub devices are half-duplex, that is, they cannot receive signals while transmitting signals;

- There is no parallel reception, ie a node or hub device cannot receive it at the same time Signals from two peer devices, because the above signals at the same frequency are likely to cause mutual interference.

 It will be understood by those skilled in the art that the above-mentioned limitations for the comparative technical effects are by no means limited to the scope of application or the scope of protection of the present invention. The utility of the present invention uses the same frequency resources, nodes and hubs for nodes and hub devices. There is no limit to whether the device can work in parallel (half-duplex, full-duplex, or other).

Based on the above premise, first look at the mesh network using the static uplink logic topology shown in Figure 5a. The signal-to-noise ratio on each uplink logical connection is 20 dB, so the spectral efficiency on each uplink logical connection is approximately C=lo _g2 (l+SNR) 6.64 bps/Hz. According to this static uplink logical topology, Router 2 can never send an uplink signal directly to the gateway 3'.

 In the first time slot shown in FIG. 5b, the router 2 sends a signal to the router ,. Those skilled in the art understand that since the router 1 needs to forward the uplink signal router 2 for the router 2, it cannot fully utilize the router and the router. 1, between 6.64bps / Hz spectral efficiency, and can only use 3.32bps / Hz. Thereafter, in the second time slot, the router sends a signal to the gateway 3, and the frequency efficiency on the link is 6.64 bps/Hz.

Thus, the total throughput in the mesh network employing the static ascending logical topology shown in Figures 5a-5c can be calculated. In two time slots, with router 2 as the starting point and gateway 3 as the end point, the amount of data transmitted in the first time slot is 0. Since no data arrives at gateway 3, the data transmitted in the second time slot is 6.64 bits, therefore, the final total spectral efficiency is

An exemplary mesh network has different uplink logical topology structures in the first and second time slots. In the uplink logical topology shown in FIG. 6a, the signal-to-noise ratio of each uplink logical connection is 20 dB. Therefore, the spectral efficiency on each uplink logical connection is approximately C=log ₂ (l+SNR). ~6.64 bps/Hz. In the uplink logic topology shown in Figure 6b, the signal-to-noise ratio of the other links is 20dB, and the signal-to-noise ratio of the router 2 to the gateway is 14dB. This value is based on Figure 6b. The distance between the various network devices shown and consider the electromagnetic waves Calculated by transferring in free space, the formula is: 20 - 101og ₁₀ (2 ² ) = 14

As can be seen from Figures 6c and 6d, in the first time slot, the router 1 performs uplink communication with the gateway 3, and the spectrum efficiency is 6.64 bps/Hz; in the second time slot, the router 2 performs the same with the gateway 3. For uplink communication, the spectral efficiency is 4.648 bps/Hz. Therefore, the total spectral efficiency in two time slots is ¹ time slot ^{X 6} . ⁶ ₂ ⁴ slot ^{X 4} . ⁶⁴⁸ = 5.6 AAb _P sl H _Z .

 Compared to the spectral efficiency of only 3.32lips/Hz in the static logic topology, the logical topology change brings about a 70% spectral efficiency increase, which is considerable.

 The benefits of the change of the logical topology in the mesh network are described above. However, as mentioned above, the logical topology of the mesh network often does not change by itself, which requires intervention by the present invention. It is ensured that the logical topology of the mesh network can be advantageously changed.

 FIG. 7 is a flow chart showing a method for uplink logical topology management in a network device of a mesh network according to an embodiment of the present invention. Hereinafter, the method portion of the present invention will be described in detail with reference to Fig. 7 in conjunction with Figs. 6a-6d.

 The uplink logical topology of the current time is shown in Figure 6a, wherein the current uplink logical topology includes the uplink logical connection of Router 2 to Router 1 and the uplink logical connection of Router 1 to Gateway 3. The method begins in step S00, in which routers 1, 2 determine if a predetermined condition is met. It is understood by those skilled in the art that since the gateway 3 is located in the uplink vertices in the mesh network shown in FIGS. 6a-6d, in other words, there is no current uplink in the network starting from the gateway 3 and pointing to other network devices. Therefore, the gateway 3 preferably does not need to perform the various steps shown in FIG. Alternatively, by pre-configuration, the gateway 3 obtains a negative judgment result each time the judgment operation in step S00 is performed.

 At routers 1, 2, when any one or more of the following conditions are met, it can be determined that the predetermined condition is satisfied:

 Condition a: A predetermined length of time has elapsed since the router previously determined a new uplink logical connection;

 Condition b: The load of the current upstream potential communication peer of the router exceeds a predetermined threshold;

Condition c: When the router randomly determines whether it is necessary to determine a new uplink logical connection, A determination result indicating that a new uplink logical connection needs to be determined is obtained.

 For the judgment of whether the condition a is satisfied, a timer can be started after each determining a new uplink logical connection, and the timer can generate an interrupt after a predetermined length of time, indicating that the condition a is satisfied, so that the cycle is repeated .

 For the judgment of condition 2, it is necessary for each router to monitor the load status of its current upstream potential communication peer. Taking Figure 6a as an example, the concept of 'uplink potential communication peer is explained: According to the uplink logic topology shown in Figure 6a, if router 1 generates uplink data, then these uplink data will only be sent to the gateway. 3. However, when performing step S00, the router 1 is not necessarily performing uplink communication with the gateway 3. For this reason, the potential is used to indicate that when the router 1 has the uplink data transmission task, the gateway 1 will become its communication pair. Otherwise, there will be only one uplink logical connection between the gateway 3 and the router 1, and there is no signal that is actually being transmitted. Those skilled in the art understand that a signal is an object for transmission generated by frequency-converting data and control information. Hereinafter, data, control information, and signals generated therefrom are collectively referred to as signals without confusion.

 Specifically, in order to determine whether the condition 2 is satisfied, according to an exemplary embodiment of the present invention, each network device queries its uplink potential peer device by means of signaling interaction according to the current uplink logical topology structure. Load condition. Those skilled in the art understand that the load condition of a network device can be characterized by a wide variety of information, typically such as the proportion of used resources in the total resources on the air interface, processor occupancy, and the like. By setting thresholds for various resources, you can determine whether condition 2 is satisfied.

 As for condition 3, its implementation includes but is not limited to: Each network device generates a random number that only takes a Boolean value every time period T is elapsed. For example, if the generated random number is 0, it means that condition 3 is satisfied, and conversely, if the value is 1, it means that condition 3 is not satisfied. Preferably, since the other network devices do not know about the determination based on the condition 3 and the subsequent determination of the new uplink logical connection, after determining based on the condition 3 and determining the new uplink logical connection, The network device needs to inform the whole network of this result. In conjunction with Figure 6a, Router 1 needs to inform Router 2 and Gateway 3 of it.

Optionally, the determination performed by the routers 1, 2 in step S00 can also be implemented by the gateway 3. For example, the gateway 3 records the previous new determination from each router. The row logically connects to the elapsed time and, after it reaches a predetermined length of time, notifies the corresponding router to determine a new upstream logical connection. In summary, the routers 1, 2 will obtain their respective judgment results in step S00. Those skilled in the art understand that, according to different embodiments of the present invention, the result of performing step S00 at the routers 1, 2 may be various, for example, the router 1 determines that the result is yes and the router 2 determines that the result is no, or both No, either router 1 determines no and Router 2 determines yes, or both. In this example, both routers 1 and 2 get a positive judgment result, and thus, a new uplink logical connection needs to be determined. This new upstream logical connection meets the following conditions:

 - starting with the corresponding router;

 - Point to a different network device near the router that is different from its current upstream potential peer device.

 Those skilled in the art understand that as long as one router re-determines a new uplink logical connection that satisfies the above conditions, the uplink logical topology shown in Figure 6a will change, resulting in the aforementioned throughput gain.

 Since both routers 1 and 2 need to determine a new uplink logical connection, at routers 1, 2, the method proceeds to the next step of step S00. As shown in FIG. 7, when the result of the step S00 is YES, the method will enter one of S01, S01, S01, wherein the three subsequent steps respectively correspond to determining a new uplink. The following exemplary techniques for logical connections:

 1) using Spatial Division Multiple Access technology, typically as beamforming technology;

 2) Use Spatial Multiplexing technology.

 3) using multiple directional directional antennas;

 4) use a variable directivity antenna, such as a steerable directional antenna;

In order to fully introduce the present invention, in this example, the router 1 has a transmit antenna array, and the router 2 has a rotatable directional antenna and a plurality of orientation fingers. PT/CN2008/001391 directional antenna.

 Thus, router 1 can determine a new uplink logical connection based on the exemplary techniques 1) or 2) above. Router 2 can use the above exemplary techniques 3), 4). Introduced as follows:

 ♦ SDMA

 Example 1

 There are many implementations of space division multiple access, of which beamforming is more typical. In accordance with one non-limiting embodiment of the present invention, router 1 implements step S01 using beamforming techniques. According to the uplink logical topology shown in FIG. 6a, for the uplink communication, corresponding to the antenna array composed of multiple transmit antennas at the router 1, a beamforming coding parameter group, wherein each beamforming parameter is a complex number, and respectively Corresponding to one of the antenna arrays in the antenna array. Each of the complex parameters weights the to-weighted symbols on the corresponding antennas to form a beam directed to the router 1 at this time as the upstream potential peer device, gateway 3.

 Specifically, in step S01, the router 1 selects a new current uplink beamforming coding parameter set from the pre-stored plurality of uplink beamforming coding parameter sets, thereby changing the uplink logical topology structure of the mesh network shown in FIG. 6a. According to the invention, each pre-stored set of uplink beamforming coding parameters corresponds to one of the other network devices in the vicinity of the router 1, i.e. one parameter group corresponds to the gateway 3 and the other corresponds to the router 2.

 According to an embodiment of the present invention, each uplink beamforming coding parameter group at the router 1 is saved in a predetermined order, thereby ensuring that each selected uplink beamforming coding parameter group is different, thereby ensuring new and old uplink logic. The connection points to a different network device.

According to a variant of the example described in the previous paragraph, the router 1 stores the respective uplink beamforming coding parameter groups in association with the corresponding other network devices, for example, using the feature information of the gateway 3 and the router 2 respectively. The corresponding uplink beamforming coding parameter set is identified. When step S01 is performed, since the current uplink potential peer device is the gateway 3, the router 1 selects the pre-stored uplink beamforming coding parameter group identified by the feature information of the router 2, and applies the transmit antenna thereto. Array. According to still another variation of the above example, the router 1 saves each uplink beamforming coding parameter set in association with a preset uplink logical topology information. Each of the preset uplink logical topology information includes at least an uplink logical connection starting from the router 1 to one other network device, for example, corresponding to the uplink beamforming coding parameter group used by the router 1 before performing step S01. The uplink logical topology information is shown as 2^13, which includes the uplink logical connection of the router 1 to the gateway 3, and also includes the optional uplink logical connection of the router 2 to the router 1. Then, when step S01 is performed, the router 1 selects an uplink beamforming coding parameter group corresponding to another preset uplink logical topology information 1^2-^3.

 According to a non-limiting embodiment of the present invention, the pre-stored plurality of uplink beamforming coding parameter sets may be obtained in the following manner. First, the router 1 obtains relative position information between it and each of the other network devices in the vicinity, and then, based on the obtained relative position information, the router 1 respectively calculates two corresponding to the uplink logical links 1^3 and 1 2 Uplink beamforming coding parameter set. For the calculation method of beamforming coding parameter group, please refer to Petre Stoica, Fellow, IEEE & Zhisong Wang, Student Member, IEEE & Jian Li, Senior Member, IEEE, IEEE SIGNAL PROCESSING LETTERS, VOL. , NO. 6, JUNE 2003 Robust Capon Beam Forming.

 In some relatively complex network environments, each node can uniformly report its location information to a hub device, and then the hub device broadcasts the location information of each node downward, or the node accesses the hub device as needed. The location information of the other nodes required is obtained, and then its relative position to the corresponding other nodes is known. For example, the routers 1, 2 report their location information with respect to the gateway 3 to the gateway 3, respectively, and then the gateway 3 notifies.

 According to a preferred embodiment of the present invention, the antenna array at the router 1 is an adaptive antenna array (Adaptive Antenna Array), which has the advantage of being in a pointing router while forming a strong main lobe pointing to the correct target such as the gateway 3. The direction of 2 can form a null (Null) to minimize interference, which is especially valuable when each network device uses the same frequency band.

In connection with the description of Embodiment 1, those skilled in the art understand that the router 1 is based on The plurality of pre-stored sets of coding parameters are used to change the uplink logical topology of the mesh network in which it is located by determining a new uplink logical connection when the aforementioned predetermined conditions are met. Then, preferably, this requires that each of the uplink beamforming coding parameter sets pre-stored at the router 1 is valid. In other words, each pre-stored set of uplink beamforming coding parameters should preferably point to one of the other network devices in the vicinity of router 1. Since the relative positions of devices such as routers and gateways are usually fixed, the above-mentioned pre-stored coding parameter sets can maintain their validity for a long period of time.

 Those skilled in the art understand that when the relative motion between the first type of network device and other network devices in the vicinity thereof is slow motion or relatively stationary, the pre-stored uplink beamforming coding parameter set is meaningful because, in one In a longer period of time, an uplink beamforming coding parameter set can determine an uplink logical connection starting from the first type of network device and pointing to another network device.

Let us consider the case where the relative motion between the first type of network device and other network devices in the vicinity thereof is a fast motion, typically, such as a mesh access network. The first mobile terminal that is far away from the access device needs to rely on a second mobile terminal to transmit an uplink signal to the access device. Initially, the users of the first and second mobile terminals are resting, and thus the relative motion between the two mobile terminals is static. In this stage, the first mobile terminal acquires a mobile terminal corresponding to the second mobile terminal. The uplink beamforming coding parameter set of the uplink logical connection is saved in association with the second mobile terminal. After a period of time, the first mobile terminal enters a car with the user, and the car then travels west, while the user of the second mobile terminal remains in place to rest, at which time, the person skilled in the art understands that the first move The uplink beamforming coding parameter group saved in association with the second mobile terminal in the terminal has not been able to point to the second mobile terminal more accurately. Therefore, preferably, the first mobile terminal monitors itself and each other network device in the vicinity. Relative motion, and after learning that it is moving rapidly relative to the second mobile terminal, deleting the uplink beamforming coding parameter set saved in association with the second mobile terminal. In addition, since the first mobile terminal moves quickly, the channel condition between it and other surrounding network devices can usually change sufficiently small in a sufficiently short time, and therefore, the channel condition in the existing sensor network To reconstruct the logical topology to achieve opportunistic communication skills The program will apply.

 Thus, those skilled in the art understand that the present invention is more suitable for situations where the relative motion therebetween is slow or stationary, as compared to the case where the first type of network device is in rapid relative motion with other network devices.

 Example 2

 In Embodiment 1, the router 1 performs step S01 depending on the pre-stored uplink beamforming coding parameter set. In the second embodiment, the router 1 does not need to pre-store such an encoded parameter array, but is generated immediately when the predetermined condition is satisfied. Specifically, router 1 periodically updates its relative location information with other nearby network devices for immediate generation of the encoded parameter array. Generally, the relative position information obtained by the router 1 and other network devices is composed of a distance parameter and an angle parameter, and can be implemented by a mature positioning technology such as TDOA.

 Taking as shown in Figs. 6a and 6b, when it is judged that the predetermined condition is satisfied in the state shown in Fig. 6a, the router 1 generates an encoding parameter group based on the relative position between itself and the router 2, and thereafter, whenever the router 1 sends an uplink signal to the router 2, and a main lobe pointing to the router 2 is formed on the antenna array. Preferably, the router 1 also considers its relative positional relationship with the gateway 3, so that whenever the router 1 sends an uplink signal to the router 2 according to the uplink logical topology shown in FIG. 6b, it can not only point to the router 2 A strong main lobe is formed in the direction, and a null can be formed in the direction pointing to the gateway 3 to avoid interference. For details, please refer to Petre Stoica, Fellow, IEEE & Zhisong Wang, Student Member, IEEE & Jian Li, Senior Member, IEEE, IEEE SIGNAL PROCESSING LETTERS, VOL. 10, NO. 6, JUNE 2003 Robust Capon Beam Forming.

 Those skilled in the art understand that the above description of the implementation of step S01 using beamforming techniques is merely an example, and the spatial division multiple access coding described in the present invention is not limited to beamforming coding.

 ♦ Space division multiplexing

 Example 3

Similar to space division multiple access coding in the case of beamforming, spatial division multiplexing coding also adds different phases and amplitudes to multiple transmit antennas to achieve the directionality of the transmitted signal. The difference is that the main purpose of general space division multiplexing is to increase the point-to-point transmission rate or reduce the bit error rate, while space division multiple access is mainly used to provide point-to-multipoint simultaneous transmission capability.

 In fact, after the router 1 obtains the relative location information between the router and the other network devices, the calculation of the uplink beamforming coding parameter group and the uplink precoding parameter group can be implemented by using the mature coding technology in the prior art, where When the precoding technique is used, the generation process of the parameter group can be seen in π· Vu & Arogyaswami Paulraj <MIMO Wireless Linear Pre-coding>, Accepted to IEEE Signal Processing Magazine, Submitted Feb 2006, revised Nov 2006 and Dec 2006.

 In view of this, the specific implementation manners of spatial division multiplexing coding and space division multiple access coding in the present invention are very similar, and therefore the case of space division multiplexing coding will not be described in detail for the sake of brevity. Those skilled in the art understand that when using the precoding technique, the router 1 can implement step S01 based on the set of uplink precoding parameters stored in association with other network devices or preset uplink logical topology information. Alternatively, when the precoding technique is used, the router 1 can also generate the uplink precoding parameter set for step S01 in real time based on its relative position information with other nearby network devices.

 Those skilled in the art understand that the above description of implementing step S01 using the precoding technique is merely an example, and the space division multiplexing code described in the present invention is not limited to precoding.

 In the above, router 1 is taken as an example to describe the process of using an antenna array to change the uplink logical topology of a mesh network. In the following, the case of using the directional directivity antenna or the variable directivity antenna will be described by taking the router 2 as an example. The related description of the router 1 is taken as a reference hereto.

 ♦ Use multiple directional directional antennas

 Example 4

 It can be understood that the directional antennas pointing in the same direction among the plurality of directional directivity antennas in this example function similarly to an antenna array after determining the spatial division coding parameters, when the router 2 is surely directed to a nearby one. When the network device sends an uplink signal, the directional directivity antenna used by the network device points to the other network device, that is, the uplink logical connection starting from the router 2 and pointing to the other network device is determined.

Thus, in accordance with one non-limiting embodiment of the present invention, router 2 will have more The directional directivity antennas having the same pointing in the directional directivity antennas are grouped into one group, and the plurality of sets of identification information are saved. Thus, in the situation shown in FIG. 6a, when the predetermined condition is satisfied, the router 2 selects another directional directional antenna group (pointing to the gateway 3) different from the currently used directional directional antenna group (pointing to the router 1). Thus, a new upstream logical connection pointing to gateway 3 starting with router 2 is determined.

 According to a specific case of this example, each of the identification information groups held at the router 2 has a specific order, and in step S01, the router 2 selects the directional directional antenna group in this particular order.

 According to another specific case of the present example, each of the identification information groups stored at the router 2 has no specific order, and in step S01, the directional directivity antenna group is randomly selected, and preferably, the router 2 places it in step S01. The identification information of the other network devices pointed to by the selected directional directivity antenna group is notified to other network devices in the mesh network. The purpose of this preferred notification step is that after the directional directional antenna group reselected by router 2 is directed to one of the other network devices in its vicinity, if the other network device itself is unable to receive multiple signals at the same time (ie, no Supporting concurrent reception), the other type of network device that wants to point the new uplink logical connection to this other network device knows that the router 2 has first directed the new uplink logical connection to the network device, if it is The same operation results in mutual interference with the router 2, so this first type of network device preferably additionally selects one network device to determine its new uplink logical connection.

 Since the pointing of the directional directivity antenna cannot be controlled by the router 2, the situation of selecting the directional directional antenna group by pre-storing, and in step S01, the selection based on the pre-stored information is preferably applied to the relative relationship between the respective network devices. A situation where the location is relatively fixed, for example, a mesh infrastructure network.

 Example 5

If there is relative motion between the router 2 and other network devices in the vicinity thereof, the router 2 needs to monitor its relative position with other network devices in the vicinity in time, and when a predetermined condition is met, determine another network device in the vicinity thereof as The new upstream potential peer device, which in turn points in the direction closest to the new upstream potential peer device Directed directional antennas (groups) to determine new upstream logical connections.

 As mentioned above, the router 2 can also rely on a variable directivity antenna to achieve S01 which acts similarly to steps S01, sor. The above description of the antenna array and the directional directivity antenna is used herein as a reference. :

 ♦ Use variable directional antenna

 Example 6

 Since the variable directivity antenna such as the rotatable directional antenna can be directed in either direction, and for economic reasons, the router 2 for implementing the step SOI' can be provided with only one variable directivity antenna.

 It can be understood that when the variable directivity antenna in this example points in a specific direction, it acts like an antenna array after determining the spatial division coding parameters, when the router 2 is surely to a nearby network. When the device sends an uplink signal, its variable directional antenna will point to the other network device, that is, determine the uplink logical connection starting from router 2 and pointing to the other network device.

 Thus, in accordance with one non-limiting embodiment of the present invention, router 2 maintains each of its plurality of specific orientations of variable directional antennas in association with one of the other network devices in its vicinity. Therefore, in the situation shown in FIG. 6a, the antenna is directed to the router 1, and when it is determined in step S00 that the predetermined condition is satisfied, the router 2 adjusts its antenna pointing to point to the gateway 3, thereby determining that the router 2 is Start point, a new upstream logical connection to gateway 3.

 According to a specific case of the present example, each pointer (shown as an angle value) held at the router 2 has a specific sequence, and in step SOI ', the router 2 selects its variable direction in this particular order. The pointing of the directional antenna.

According to another specific case of this example, each pointer stored at the router 2 has no specific order, and a pointer is randomly selected from the step sor, and preferably, the router 2 selects it in step SOI ', The identification information of the other network device corresponding to the new pointer of the variable antenna group is notified to other network devices in the mesh network. The purpose of this preferred notification step is that after the variable directional antenna of router 2 is angled to point to another network device in its vicinity, if this other The network device itself cannot receive multiple signals at the same time (ie, does not support concurrent reception), and other network devices of the first type that want to point the new uplink logical connection to this other network device know that the router 2 has already advanced. The new uplink logical connection points to this network device, and if it does the same operation, it will cause mutual interference with the router 2. Therefore, this first type of network device preferably additionally selects a network device to determine its new Uplink logical connection.

 According to the present invention, as the uplink logical topology changes, it is necessary to determine in the mesh network which device can transmit signals on the current uplink logical connection and which are not. In addition, the network also needs to allocate resources for the transmission of the above signals, which can be supported by existing scheduling technologies such as professional fairness and new technologies that may emerge in the future, and please see David Tse & Stephen Hanly for details. , <Multi-Access Fading Channels: Part I: Polymatroid Structure, Optimal Resource Allocation and Throughput Capacities , IEEE Transactions on Information Theory, v. 44(7), Nov., 1998.

 Those skilled in the art understand that even if the scheduling, resource allocation, routing, etc. after the change of the logical topology structure are not introduced, the full disclosure of the present invention is not affected, in order to make the idea of the present application easier to understand, The characteristics of the processing process after the logical topology structure change of the present invention are described as follows:

 The present invention is used to realize opportunistic communication, and the core idea of opportunistic communication is exactly: communication is good when the channel condition is good, and communication is not performed when the channel condition is not good. Therefore, after the logical topology changes, whether a mobile terminal should use its current uplink logical connection to send a signal to its current upstream potential peer device depends on the channel condition corresponding to the uplink logical connection, for example, A predetermined threshold is set for the channel gain, which is allowed to transmit an uplink signal when the actual channel gain reaches or exceeds the predetermined threshold.

 In addition, when performing routing, the principle of minimum hop count, the principle of minimum channel attenuation, and the like can be considered, and will not be described again.

Hereinafter, the specific device of the present invention will be described in detail with reference to the block diagrams 8, 9 and in conjunction with Figs. 6a-6d. FIG. 8 is a block diagram showing an uplink topology management apparatus for uplink logical topology management in a network device of a mesh network according to an embodiment of the present invention, FIG. 9 is a block diagram showing FIG. A block diagram of a downlink topology management apparatus for downlink logical topology management in a network device of a mesh network according to an embodiment of the present invention. In the following, the uplink topology management device will be described in detail with reference to FIG. 9. According to this part, the person skilled in the art can implement the downlink topology management device without creative labor.

 The illustrated uplink topology management device 10 includes: a first determination device 100, a first determination device 101, a first parameter group acquisition device 102, a first storage device 103, a first location information obtaining device 104, and a first detection device 105. The first deletion device 106 and the second location information obtaining device 107. The first determining device 101 includes a first pointing determining device 1010 and a first pointing adjusting device 101 1 .

 The uplink logical topology of the current time is shown in Figure 6a, wherein the current uplink logical topology includes the uplink logical connection of Router 2 to Router 1 and the uplink logical connection of Router 1 to Gateway 3. First, the first judging means 100 at the routers 1, 2 judges whether or not a predetermined condition is satisfied. Those skilled in the art understand that since the gateway 3 is located in the uplink vertices in the mesh network shown in Figures 6a-6d, in other words, there is no current uplink in the network starting from the gateway 3 and pointing to other network devices. Thus, based on the network environment shown in Figures 6a-6d, the gateway 3 preferably does not need to include the upstream topology management device 10. Alternatively, by the pre-configuration, the first judging device 100 at the gateway 3 obtains a negative judgment result each time the judgment operation is performed.

 At routers 1, 2, when any one or more of the following conditions are met, it can be determined that the predetermined condition is satisfied:

 Condition a: A predetermined length of time has elapsed since the router previously determined a new uplink logical connection;

 Condition b: The load of the current upstream potential communication peer of the router exceeds a predetermined threshold;

 Condition c: When the router randomly determines whether it is necessary to determine a new uplink logical connection, a judgment result indicating that a new uplink logical connection needs to be determined is obtained.

For the judgment of whether the condition a is satisfied, a timer can be started after each determining a new uplink logical connection, and the timer can generate an interrupt after a predetermined length of time, indicating that the condition a is satisfied, so that the cycle is repeated . For the judgment of condition 2, it is necessary for each router to monitor the load status of its current upstream potential communication peer. Taking Figure 6a as an example, the concept of 'uplink potential communication peer is explained: According to the uplink logic topology shown in Figure 6a, if router 1 generates uplink data, then these uplink data will only be sent to the gateway. 3, however, when the first judging device 100 performs the judging operation, the router 1 is not necessarily performing uplink communication with the gateway 3. For this reason, the 'potential' is used to indicate that when the router 1 has the uplink data transmission task, the gateway 1 will It will become its communication peer. Otherwise, there will be only one uplink logical connection between the gateway 3 and the router 1, and there is no signal that is actually being transmitted. Those skilled in the art understand that a signal is an object for transmission generated by frequency-converting data and control information. Hereinafter, data, control information, and signals generated therefrom are collectively referred to as signals without confusion.

 Specifically, in order to determine whether the condition 2 is satisfied, according to an exemplary embodiment of the present invention, each network device queries its uplink potential peer device by means of signaling interaction according to the current uplink logical topology structure. Load condition. Those skilled in the art understand that the load condition of a network device can be characterized by a wide variety of information, typically such as the proportion of used resources in the total resources on the air interface, processor occupancy, and the like. By setting thresholds for various resources, you can determine whether condition 2 is satisfied.

 As for condition 3, its implementation includes but is not limited to: Each network device generates a random number that only takes a Boolean value every time period T is elapsed. For example, if the generated random number is 0, it means that condition 3 is satisfied, and conversely, if the value is 1, it means that condition 3 is not satisfied. Preferably, since the other network devices do not know about the determination based on the condition 3 and the subsequent determination of the new uplink logical connection, after determining based on the condition 3 and determining the new uplink logical connection, The network device needs to inform the whole network of this result. In conjunction with Figure 6a, Router 1 needs to inform Router 2 and Gateway 3 of it.

Alternatively, the determination performed by the first determining device 100 at the routers 1, 2 may also be implemented by the gateway 3. For example, the gateway 3 records the elapsed time from the previous determination of the new uplink logical connection by each router, and notifies the first judging device 100 on the corresponding router after it reaches a predetermined length of time, and then determines by the first Device 101 determines a new upstream logical connection. In summary, the first determining devices 100 at the routers 1, 2 will each obtain their respective judgment results. Those skilled in the art understand that, according to different embodiments of the present invention, the judgment result obtained by the routers 1, 2 may be various, for example, the router 1 determines that the result is yes and the router 2 determines that the result is no, or both, Either router 1 determines that the result is no and router 2 determines that the result is yes, or both. In this example, both routers 1 and 2 get a positive judgment result, and then the first determining means 101 is instructed to determine a new uplink logical connection. This new upstream logical connection meets the following conditions:

 - starting with the corresponding router;

 - Point to a different network device near the router that is different from its current upstream potential peer device.

 Those skilled in the art understand that as long as one router re-determines a new uplink logical connection that satisfies the above conditions, the uplink logical topology shown in Figure 6a will change, resulting in the aforementioned throughput gain.

 Since both routers 1, 2 need to determine new uplink logical connections, subsequent operations at routers 1, 2 are typically based on the following techniques:

 1) using Spatial Division Multiple Access technology, typically as beamforming technology;

 2) using Spatial Multiplexing technology;

 3) using multiple directional directional antennas;

 4) Use a variable directivity antenna such as a steerable directional antenna.

 In order to fully introduce the present invention, in this example, router 1 has a transmit antenna array, and router 2 has a rotatable directional antenna and a plurality of directional antennas.

 Thus, router 1 can determine a new uplink logical connection based on the exemplary techniques 1) or 2) above. Router 2 can use the above exemplary techniques 3), 4). Introduced as follows:

♦ SDMA Example 7

 There are many implementations of space division multiple access, of which beamforming is more typical. In accordance with one non-limiting embodiment of the present invention, router 1 uses beamforming techniques to determine a new uplink logical connection. According to the uplink logical topology shown in FIG. 6a, for the uplink communication, corresponding to the antenna array composed of multiple transmit antennas at the router 1, a beamforming coding parameter group, wherein each beamforming parameter is a complex number, and respectively Corresponding to one of the antenna arrays in the antenna array. Each of the complex parameters weights the to-weighted symbols on the corresponding antennas to form a beam directed to the router 1 at the current upstream peer device, gateway 3.

 Specifically, the first determining device 101 of the router 1 selects a new current uplink beamforming coding parameter group from the plurality of uplink beamforming coding parameter groups prestored by the first storage device 103, thereby changing the mesh network shown in FIG. 6a. Uplink logic topology. According to the invention, each pre-stored set of uplink beamforming coding parameters corresponds to one of the other network devices in the vicinity of the router 1, i.e. one parameter group corresponds to the gateway 3 and the other corresponds to the router 2.

 According to an embodiment of the present invention, the first saving device 103 of the router 1 saves each uplink beamforming coding parameter group in a predetermined order, thereby ensuring that each selected uplink beamforming coding parameter group is different, thereby ensuring New and old uplink logical connections point to different network devices.

 According to a variant of the example described in the previous paragraph, the first saving means 103 at the router 1 stores the respective uplink beamforming coding parameter sets in association with corresponding other network devices, for example, gateway 3, router respectively. The feature information of 2 identifies the corresponding uplink beamforming coding parameter set. When the first determining device 101 is working, since the current uplink potential peer device is the gateway 3, it selects the pre-stored uplink beamforming coding parameter group identified by the feature information of the router 2, and applies it to the router 1. Transmitting antenna array.

According to still another variation of the above example, the first saving means 103 of the router 1 saves each of the uplink beamforming coding parameter sets in association with a predetermined uplink logical topology information. Each preset uplink logical topology information includes at least the beginning For the uplink logical connection of the router 1 to one of the other network devices, for example, before the first determining device 101 works, the uplink logical topology information corresponding to the uplink beamforming coding parameter group used by the router 1 is visually shown as 2^1^ 3, which includes the uplink logical connection of Router 1 to Gateway 3, and also includes the optional uplink logical connection of Router 2 to Router 1. Thus, when the first determining means 101 is in operation, an uplink beamforming coding parameter set corresponding to another predetermined uplink logical topology information 1 2^3 is selected.

 According to a non-limiting embodiment of the present invention, the pre-stored plurality of uplink beamforming coding parameter sets may be obtained in the following manner. First, the first location information obtaining means 104 at the router 1 obtains the relative location information between the router 1 and each of the other network devices in the vicinity, and then, according to the obtained relative location information, the first parameter group acquisition at the router 1 The device 102 calculates two uplink beamforming coding parameter sets corresponding to the uplink logical links 1-3 and 1-2, respectively.

 In some relatively complex network environments, each node can uniformly report its location information to a hub device, and then the hub device broadcasts the location information of each node downward, or the node accesses the hub device as needed. The location information of the other nodes required is obtained, and then its relative position to the corresponding other nodes is known. For example, the routers 1, 2 report their location information with respect to the gateway 3 to the gateway 3, respectively, and then the gateway 3 notifies.

 According to a preferred embodiment of the invention, the antenna array at the router 1 is an adaptive antenna array (Adaptive Antenna Array), which has the advantage of being in a pointing router while forming a strong main lobe pointing to the correct target such as the gateway 3. The direction of 2 can form a null (Null) to minimize interference, which is especially valuable when each network device uses the same frequency band.

In connection with the description of Embodiment 1, the person skilled in the art understands that the first determining means 101 at the router 1 is based on the pre-stored plurality of encoding parameter sets to complete the logical topology in the aforementioned predetermined condition. Then, preferably, this requires that each of the uplink beamforming coding parameter sets pre-stored at the router 1 is valid. In other words, each pre-stored uplink beamforming The set of code parameters should preferably point to one of the other network devices in the vicinity of router 1. Since the relative positions of devices such as routers and gateways are usually fixed, the above-mentioned pre-stored coding parameter sets can maintain their validity for a long period of time.

 Those skilled in the art understand that when the relative motion between the first type of network device and other network devices in the vicinity thereof is slow motion or relatively stationary, the pre-stored uplink beamforming coding parameter set is meaningful because, in one In a longer period of time, an uplink beamforming coding parameter set can determine an uplink logical connection starting from the first type of network device and pointing to another network device.

 Let us consider the case where the relative motion between the first type of network device and other network devices in the vicinity thereof is a fast motion, typically, such as a mesh access network. The first mobile terminal that is far away from the access device needs to rely on a second mobile terminal to transmit an uplink signal to the access device. Initially, the users of the first and second mobile terminals are resting, and thus the relative motion between the two mobile terminals is static. In this stage, the first mobile terminal acquires a mobile terminal corresponding to the second mobile terminal. The uplink beamforming coding parameter set of the uplink logical connection is saved in association with the second mobile terminal. After a period of time, the first mobile terminal enters a car with the user, and the car then travels west, while the user of the second mobile terminal remains in place to rest, at which time, the person skilled in the art understands that the first move The uplink beamforming coding parameter group saved in association with the second mobile terminal in the terminal may not be more accurately pointed to the second mobile terminal. Therefore, preferably, the uplink topology management device 10 at the first mobile terminal has a first The detecting device 105 is configured to monitor relative motion between the first mobile terminal and each of the other network devices in the vicinity, and after learning that the mobile device is fast moving relative to the second mobile terminal, the first deleting device 106 and the second mobile terminal The associated uplink beamforming coding parameter set is deleted. In addition, since the first mobile terminal moves quickly, the channel condition between it and other surrounding network devices can usually change sufficiently small in a sufficiently short time, and therefore, the channel condition in the existing sensor network A technical solution to reconstruct the logical topology to achieve opportunistic communication will apply.

Thus, those skilled in the art understand that the present invention is more suitable for the relative motion therebetween than the case where the first type of network device performs rapid relative motion with other network devices. Slow or static situation.

 Example 8

 In Embodiment 7, the first determining means 101 in the router 1 relies on the pre-stored set of uplink beamforming coding parameters to determine a new uplink logical connection. In the seventh embodiment, the router 1 does not need to pre-store such a group of encoding parameters, but is generated by the first determining means 101 when the predetermined condition is satisfied. Specifically, the second location information obtaining means 107 at the router 1 periodically updates the relative location information between the router 1 and other nearby network devices in preparation for immediate generation of the encoding parameter set. Generally, the relative position information between the router 1 and other network devices obtained by the second location information obtaining device at the router 1 is composed of a distance parameter and an angle parameter, and can be implemented by a mature positioning technology such as TDO A.

 Taking as shown in FIGS. 6a and 6b, when it is judged that the predetermined condition is satisfied in the state shown in FIG. 6a, the first determining means 101 at the router 1 generates an encoding parameter based on the relative position between itself and the router 2. Group, thereafter, whenever router 1 sends an upstream signal to router 2, a main lobe pointing to router 2 is formed on its antenna array. Preferably, the first determining means 101 at the router 1 also considers its relative positional relationship with the gateway 3, so that whenever the router 1 transmits an uplink signal to the router 2 in accordance with the uplink logical topology shown in FIG. 6b Not only can a strong main lobe be formed in the direction pointing to the router 2, but also a zero trap can be formed in the direction pointing to the gateway 3 to avoid interference.

 Those skilled in the art understand that the above description of the implementation of step S01 using beamforming techniques is merely an example, and the spatial division multiple access coding described in the present invention is not limited to beamforming coding.

 ♦ Space division multiplexing

 Example 9

 Similar to space division multiple access coding, such as beamforming, space division multiplexing coding also adds different phases and amplitudes to multiple transmit antennas to achieve the directionality of the transmitted signal. The difference is that the main purpose of general space division multiplexing is to increase the point-to-point transmission rate or reduce the bit error rate, while space division multiple access is mainly used to provide point-to-multipoint simultaneous transmission capability.

In fact, Router 1 is getting its relative location letter with other network devices. After the information, the calculation of the uplink beamforming coding parameter group and the uplink precoding parameter group can be implemented by relying on the mature coding technology in the prior art. When the precoding technique is adopted, the generation process of the parameter group can be seen in detail. Vu & Arogyaswami Paulraj <MIMO Wireless Linear Pre-coding>, Accepted to IEEE Signal Processing Magazine, Submitted Feb 2006, revised Nov 2006 and Dec 2006.

 In view of this, the specific implementation manners of spatial division multiplexing coding and space division multiple access coding in the present invention are very similar, and therefore the case of space division multiplexing coding will not be described in detail for the sake of brevity. It is understood by those skilled in the art that when the precoding technique is used, the first determining means 101 at the router 1 can determine based on the uplink precoding parameter set saved in association with other network devices or preset uplink logical topology information. New upstream logical connection. Alternatively, when the precoding technique is used, the first determining device 101 at the router 1 may also generate an uplink for determining a new uplink logical connection in real time based on the relative location information between the router 1 and other nearby network devices. Precoding parameter group.

 Those skilled in the art understand that the above description of using the precoding technique is merely an example, and the space division multiplexing coding described in the present invention is not limited to precoding.

 In the above, router 1 is taken as an example to describe the process of using an antenna array to change the uplink logical topology of a mesh network. In the following, the case of using the directional directivity antenna or the variable directivity antenna will be described by taking the router 2 as an example. The related description of the router 1 is taken as a reference hereto.

 ♦ Use multiple directional directional antennas

 Example 10

 It can be understood that the directional antennas pointing in the same direction among the plurality of directional directivity antennas in this example function similarly to an antenna array after determining the spatial division coding parameters, when the router 2 is surely directed to a nearby one. When the network device sends an uplink signal, the directional directivity antenna used by the network device points to the other network device, that is, the uplink logical connection starting from the router 2 and pointing to the other network device is determined.

Thus, in accordance with one non-limiting embodiment of the present invention, the router 2 groups the directional directional antennas having the same orientation among the plurality of directional directivity antennas thereon, and stores the plurality of sets of identification information, the above saving Operation may preferably be performed by the first holding device 103 to execute. Thus, in the situation shown in Fig. 6a, when the predetermined condition is satisfied, the first determining means 101 at the router 2 selects another directional directional antenna different from the currently used directional directional antenna group (pointing to the router 1). Group (pointing to gateway 3) to determine a new upstream logical connection to gateway 3 starting with router 2.

 According to a specific case of the present example, each of the identification information blocks held by the first holding means 103 at the router 2 has a specific order, and the first determining means 101 selects the directional directivity antenna group in this particular order.

 According to another specific case of the example, the respective identification information groups held by the first saving device 103 at the router 2 have no specific order, and the first determining device 101 randomly selects the directional directional antenna group, and preferably, the router 2 The identification information of other network devices pointed by the directional directivity antenna group selected by the first determining device 101 is notified to other network devices in the mesh network. The purpose of this preferred notification operation is that after the directional directional antenna group reselected by router 2 points to one of the other network devices in its vicinity, if the other network device itself cannot receive multiple signals at the same time (ie, no Supporting concurrent reception), the other type of network device that wants to point the new uplink logical connection to this other network device knows that the router 2 has first directed the new uplink logical connection to the network device, if it is The same operation results in mutual interference with the router 2, so this first type of network device preferably additionally selects one network device to determine its new uplink logical connection.

 Since the orientation of the directional directivity antenna cannot be controlled by the router 2, the situation in which the identification information of the directional directional antenna group is pre-stored and selected based on the pre-stored information is preferably applied to the relative position between the respective network devices. Situation, for example, network infrastructure network.

 Example 11

If there is relative motion between the router 2 and other network devices in the vicinity thereof, the router 2 needs to monitor its relative position with other network devices in the vicinity in time, and when a predetermined condition is met, determine another network device in the vicinity thereof as The new upstream potential peer device, in turn, is directed in the direction of the directional directional antenna (group) closest to the new upstream potential peer device to determine the new uplink logical connection. Relative position The monitoring can be implemented by the first location information obtaining means 104 or the second location information obtaining means 107.

 As previously mentioned, the effects of the plurality of directional directivity antennas described above may also be made variable to directional antennas. The above description of the antenna array and directional directional antennas is hereby incorporated by reference:

 ♦ Use variable directional antenna

 Example 12

 Since the variable directivity antenna such as the rotatable directional antenna can be directed in either direction, the number of variable directivity antennas of the router 2 can be one for economic reasons.

 It can be understood that when the variable directivity antenna in this example points in a specific direction, it acts like an antenna array after determining the spatial division coding parameters, when the router 2 is surely to a nearby network. When the device sends an uplink signal, its variable directional antenna will point to the other network device, that is, determine the uplink logical connection starting from router 2 and pointing to the other network device.

 Thus, in accordance with one non-limiting embodiment of the present invention, router 2 saves each of its plurality of specific orientations of variable directional antennas in association with one of its other network devices in the vicinity, specifically by the first save The device 103 performs the save operation. Thus, in the situation shown in FIG. 6a, the antenna is directed to the router 1, and when the first determining means 100 determines that the predetermined condition is satisfied, the first pointing determining means 1010 at the router 2 is the variable directivity antenna. Determining a new pointing, and adjusting the pointing of the antenna by the first pointing adjustment device 101 1 to point to the gateway 3, thereby determining a new uplink logical connection pointing to the gateway 3 starting from the router 2 .

 According to a specific case of the present example, each of the pointers (reflected as angle values) held at the router 2 has a specific order, and the first pointing determining means 1010 selects the variable directional antenna in this particular order. Pointing.

According to another specific case of the present example, the respective pointers stored at the router 2 have no specific order, and the first pointing determining means 1010 randomly determines a pointing therefrom. Preferably, the router 2 will first determine the pointing device 1010. Notifying the mesh network of the identification information of the other network device corresponding to the new pointer of the determined variable antenna group Other network devices in the network. The purpose of this preferred notification step is that after the variable directional antenna of router 2 is directed to an other network device in its vicinity, if the other network device itself is unable to receive multiple signals at the same time ( That is, if the concurrent reception is not supported, the other type of network device that wants to point the new uplink logical connection to the other network device knows that the router 2 has first directed the new uplink logical connection to the network device. If the same operation is performed by itself, it will cause mutual interference with the router 2. Therefore, this first type of network device preferably additionally selects one network device to determine its new uplink logical connection.

 According to the present invention, as the uplink logical topology changes, it is necessary to determine in the mesh network which device can transmit signals on the current uplink logical connection and which are not. In addition, the network also needs to allocate resources for the transmission of the above signals, which can be supported by existing scheduling technologies such as professional fairness and new technologies that may emerge in the future, and please see David Tse & Stephen Hanly for details. , <Multi-Access Fading Channels: Part I: Polymatroid Structure, Optimal Resource Allocation and Throughput Capacities , IEEE Transactions on Information Theory, v. 44(7), Nov., 1998.

 Those skilled in the art understand that even if the scheduling, resource allocation, routing, etc. after the change of the logical topology structure are not introduced, the full disclosure of the present invention is not affected, in order to make the idea of the present application easier to understand, The characteristics of the processing process after the logical topology structure change of the present invention are described as follows:

 The present invention is used to realize opportunistic communication, and the core idea of opportunistic communication is exactly: communication is good when the channel condition is good, and communication is not performed when the channel condition is not good. Therefore, after the logical topology changes, whether a mobile terminal should use its current uplink logical connection to send a signal to its current upstream potential peer device depends on the channel condition corresponding to the uplink logical connection, for example, A predetermined threshold is set for the channel gain, which is allowed to transmit an uplink signal when the actual channel gain reaches or exceeds the predetermined threshold.

In addition, when performing routing, the principle of minimum hop count, the principle of minimum channel attenuation, and the like can be considered, and will not be described again. Figures 10a-10f show the results of simulating the invention under beamforming. 10a shows the physical layer configuration of the simulation. The six transmitting antennas form a regular hexagonal transmitting antenna array, and the distance between two adjacent antennas is 0.5 wavelength. Figure 10b shows the direction of the beam's target direction, ie the direction of the main lobe and the direction of the interference produced in a simulation, ie the direction indicated by null. In Figs. 10c, 10d, the simulation results in Euclidean coordinates are shown, wherein the abscissa in Fig. 10c is the direction, the ordinate is the antenna gain in the corresponding direction; the abscissa in Fig. 10d is the direction, The ordinate is the antenna gain (logarithm) in the corresponding direction. The simulation results in polarization coordinates are shown in Figures 10e and 10f, where Figure 10e is the antenna pattern and Figure 10f is the same antenna pattern, but the gain is logarithmically. Although the above uses the antenna array, the directional directivity antenna, and the variable directivity antenna in a classified manner, those skilled in the art understand that the introduction of the separation is only for the sake of clarity of description. The same applies to the case where two or all of an antenna array, a directional directivity antenna, and a variable directivity antenna are used in combination on the same first type of network device, and all of these situations fall within the protection of the claims of the present application. In the range.

 The specific embodiments of the present invention have been described above. It is to be understood that the invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the appended claims.

Claims

Claim A method for uplink logical topology management in a first type of network device of a mesh network, wherein the first type of network device has an antenna array and/or one or more directional antennas, The antenna array or one of the directional antennas determines a current uplink logical connection starting from the first type of network device and directed to its current upstream potential peer device, the method comprising the steps of:  a. determine whether the predetermined conditions are met;  Determining, based on the antenna array or the one or more directional antennas, a new uplink logical connection starting from the first type of network device, where the predetermined condition is met, wherein the new uplink logic The connection points to a new upstream potential peer device that is different from the current upstream potential peer device.  2. The method according to claim 1, wherein the step a comprises: determining that the predetermined condition is satisfied when any one of the following conditions is satisfied:  - a predetermined length of time has elapsed since the first type of network device last determined a new uplink logical connection;  - the load of the current upstream potential communication peer of the first type of network device exceeds a predetermined threshold;  - When the first type of network device randomly determines whether a new uplink logical connection needs to be determined, a determination result indicating that a new uplink logical connection needs to be determined is obtained.  The method according to claim 1 or 2, wherein the first type of network device has a plurality of directional directivity antennas, each of the directional directional antennas pointing to the vicinity of the first type of network device And one of the other network devices, wherein the one or more of the directional directional antennas determine a current uplink logical connection starting from the first type of network device and pointing to the current uplink potential peer device, the step b further comprising:  Bl '. Select one or more directional directivity antennas from the remaining directional directivity antennas, wherein the selected one or more directional directivity antennas determine the new uplink logical connection. The method according to claim 1 or 2, wherein the first type of network The network device has a variable directivity antenna, and the current direction of the variable directivity antenna determines a current uplink logical connection starting from the first type of network device and pointing to its current upstream potential peer device, Step b also includes:  Bl". determining a new orientation for the variable directivity antenna;  B2". The variable directional antenna is adjusted to point to the new pointer, and the adjusted variable directional antenna determines the new uplink logical connection.  The method according to claim 1, wherein the first type of network device has an antenna array, and the antenna array determines the current uplink based on a current uplink spatial coding parameter group corresponding thereto. Logical connection, the step b includes:  Selecting an uplink space division coding parameter group different from the current uplink space division coding parameter group by using a plurality of uplink space division coding parameter groups prestored by the first type network device as the new current uplink space coding Parameter group.  The method according to claim 5, further comprising: before the step bl:  Obtaining an uplink space division coding parameter group respectively determined according to the relative location information between the network device of the first type and each of the other network devices in the vicinity, where each obtained uplink space coding group corresponds to The first type of network device is a starting point and points to an uplink logical connection of the corresponding other network device;  III. The obtained uplink space coding parameter group is saved in association with the corresponding other network device;  The step bl further includes:  - Select one of the other network parameter sets that were previously different from the current upstream potential peer device.  The method according to claim 6, wherein the step II further comprises:  I. obtaining relative location information between the first type of network device and each of the other network devices in the vicinity; The step II further includes: - calculating an uplink space division coding parameter group according to the relative position information between the first type of network device and each of the other network devices in the vicinity.  The method according to claim 6 or 7, wherein the step III further comprises:  - storing each of the acquired uplink space division coding parameter groups in association with a preset uplink logic topology information, wherein each of the preset uplink logic topology information is included in The plurality of uplink logical connections starting from the first type of network device and the other one or more first type network devices and pointing to their respective uplink potential peer devices at the same time,  The pre-set uplink logical topology information includes a current uplink logical topology information, which includes starting, by using the first type network device and the other one or more first type network devices respectively. Multiple current uplink logical connections to their respective current upstream potential peer devices;  The step bl further includes:  - selecting an uplink spatial coding parameter set previously stored in association with another uplink logical topology information different from the current uplink logical topology information as the new current uplink spatial coding parameter group.  The method according to claim 6, wherein the mesh network comprises a mesh access network and/or a mesh infrastructure network, wherein when the mesh network is a mesh access network , the method also includes:  - detecting whether it is in a relatively slow motion or a relatively stationary state with each other nearby network device;  - deleting the uplink space code previously stored in association with the one or more other network devices when it is detected that it is not in a relatively slow motion or a relatively stationary state with one or more other network devices in the vicinity Parameter group.  The method according to claim 1, wherein the step b further comprises: Obtaining relative location information between the first type of network device and one or more other nearby network devices; The step b further includes:  Obtaining respective new uplink space division coding parameter groups in cooperation with the other one or more first type network devices according to the obtained relative location information between the network devices and other nearby network devices;  The new uplink space division coding parameter group acquired by the first type network device corresponds to an uplink starting from the first type network device and pointing to another network device different from the current uplink potential peer device. Logical connection.  The method according to claim 5 or 10, wherein the space division coding comprises space division multiplexing coding and space division multiple access coding.  12. The method according to claim 11, wherein the space division multiplexing coding comprises precoding, and the space division multiple access coding comprises beamforming coding.  13. Method according to claim 5 or 10, characterized in that the antenna array is an adaptive antenna array.  14. A method for downlink logical topology management in a first type of network device of a mesh network, wherein the first type of network device has an antenna array and/or one or more directional antennas, The antenna array or one of the directional antennas determines a current downlink logical connection starting from the first type of network device and directed to its current downstream potential peer device, the method comprising the steps of:  A. Determine whether the predetermined condition is satisfied;  B. determining, when the predetermined condition is satisfied, a new downlink logical connection starting from the first type of network device based on the antenna array or the one or more directional antennas, wherein the new downlink logic The connection points to a new downstream potential peer device that is different from the current downstream potential peer device.  The method according to claim 14, wherein the step A comprises: determining that the predetermined condition is satisfied when any one of the following conditions is satisfied:  - a predetermined length of time has elapsed since the first type of network device last determined a new downlink logical connection; - the load of the current downlink potential communication peer of the first type of network device exceeds a predetermined threshold; - When the first type of network device randomly determines whether a new downlink logical connection needs to be determined, a determination result indicating that a new downlink logical connection needs to be determined is obtained.  16. The method according to claim 14 or 15, wherein the first type of network device has a plurality of directional directivity antennas, each of the directional directional antennas pointing to the vicinity of the first type of network device And one of the other network devices, wherein the one or more of the directional directional antennas determine a current downlink logical connection starting from the first type of network device and pointing to the current downlink potential peer device, the step b further comprising:  一个. Selecting one or more directional directivity antennas from the remaining directional directivity antennas, wherein the selected one or more directional directivity antennas determine the new downlink logical connection.  The method according to claim 14 or 15, wherein the first type of network device has a variable directivity antenna, and the variable directivity antenna is determined by the first type of network device The starting point is the current downlink logical connection of the current downstream potential peer device, and the step b further includes:  B1". determining a new orientation for the variable directivity antenna;  B2". Adjusting the variable directivity antenna to point to the new pointer, and the adjusted variable directivity antenna determines the new downlink logical connection.  The method according to claim 14, wherein the first type of network device has an antenna array, and the antenna array determines the current downlink based on a current downlink spatial coding parameter group corresponding thereto. Logical connection, the step B includes:  B1. Selecting, by the first type network device, a downlink space division coding parameter group different from the current downlink space division coding parameter group as a new current downlink space coding. Parameter group.  The method according to claim 18, wherein before the step B1, the method further comprises: Obtaining a downlink space division coding parameter group respectively determined according to relative position information between the network device of the first type and each of the other network devices in the vicinity, where each obtained downlink space coding group corresponds to The first type of network device is a starting point and points to a downlink logical connection of the corresponding other network device; Q. The obtained downlink space division coding parameter group is saved in association with the corresponding other network device;  The step B1 further includes:  - selecting a downlink space division coding parameter set previously saved in association with one other network device different from the current downlink potential peer device as the new current downlink space division coding parameter group.  The method according to claim 19, wherein the step P further comprises:  Obtaining relative location information between the first type of network device and each of the other network devices in the vicinity;  The step P further includes:  - calculating a downlink space division coding parameter group based on the relative position information between the first type of network device and each of the other nearby network devices.  The method according to claim 19 or 20, wherein the step Q further comprises:  - storing each of the acquired uplink space division coding parameter groups in association with a preset downlink logic topology information, wherein each of the preset downlink logic topology information is included in The plurality of downlink logical connections starting from the first type of network device and the other one or more first type network devices and pointing to their respective downlink potential peer devices at the same time,  The each of the preset downlink logical topology information includes a current downlink logical topology information, which includes starting with the first type network device and the other one or more first type network devices respectively. Multiple current downlink logical connections to their respective current downstream potential peer devices;  The step B1 further includes:  - selecting a downlink space division coding parameter set previously saved in association with another downlink logical topology information different from the current downlink logical topology information as the new current downlink spatial division coding parameter set. 22. The method of claim 19, wherein the mesh network comprises The mesh access network and/or the mesh infrastructure network, wherein when the mesh network is a mesh access network, the method further includes:  - detecting whether it is in a relatively slow motion or a relatively stationary state with each other nearby network device;  - Deleting a downlink space code previously stored in association with the one or more other network devices when it is detected that it is not in a relatively slow motion or a relatively stationary state with one or more other network devices in the vicinity Parameter group.  The method according to claim 14, wherein the step B further comprises:  Obtaining relative location information between the first type of network device and one or more other nearby network devices;  The step B further includes:  Obtaining respective new downlink space division coding parameter groups in cooperation with the other one or more first type network devices according to the obtained relative location information between the network devices and other nearby network devices;  The new downlink space division coding parameter group acquired by the first type network device corresponds to the downlink of the first type network device and points to another network device different from the current downlink potential peer device. Logical connection.  The method according to claim 18 or 23, wherein the space division coding comprises space division multiplexing coding and space division multiple access coding.  The method according to claim 24, wherein the space division multiplexing coding comprises precoding, and the space division multiple access coding comprises beamforming coding.  The method according to claim 18 or 23, wherein the antenna array is an adaptive antenna array. 27. An uplink topology management apparatus for uplink logical topology management in a first type of network device of a mesh network, wherein the first type of network device has an antenna array and/or one or more The directional antenna, the antenna array or one of the directional antennas determines a current uplink logical connection starting from the first type of network device and pointing to its current uplink potential peer device, where the uplink topology management device includes: a first determining device, configured to determine whether the predetermined condition is satisfied;  a first determining means, configured to determine, according to the antenna array or the one or more directional antennas, a new uplink logical connection starting from the first type of network device when a predetermined condition is met,  The new uplink logical connection points to a new uplink potential peer device different from the current uplink potential peer device.  The uplink topology management apparatus according to claim 27, wherein the first determining means is configured to: when any one of the following conditions is satisfied, determine that the predetermined condition satisfies:  - a predetermined length of time has elapsed since the first type of network device last determined a new uplink logical connection;  - the load of the current upstream potential communication peer of the first type of network device exceeds a predetermined threshold;  - When the first type of network device randomly determines whether a new uplink logical connection needs to be determined, a determination result indicating that a new uplink logical connection needs to be determined is obtained.  The uplink topology management device according to claim 27 or 28, wherein the first type of network device has a plurality of directional directivity antennas, each of the directional directional antennas pointing to the first An other network device in the vicinity of the type network device, wherein the one or more of the directional directivity antennas determine a current uplink logical connection starting from the first type of network device and pointing to its current upstream potential peer device,  The first determining means is further configured to: select one or more directional directional antennas from the remaining directional directional antennas, wherein the selected one or more directional directional antennas determine the new uplink logical connection.  The uplink topology management device according to claim 27 or 28, wherein the first type of network device has a variable directivity antenna, and the current orientation of the variable directivity antenna is determined. The first determining device includes: the first type of the network device as the starting point and the current uplink logical connection of the current uplink potential peer device. a first pointing determining device, configured to determine a new pointing for the variable directivity antenna; a first pointing adjustment device, configured to adjust the variable directivity antenna to point to the new pointing, and the adjusted variable directivity antenna determines the new uplink logical connection.  The uplink topology management device according to claim 27, wherein the first type of network device has an antenna array, and the antenna array is determined based on a current uplink spatial coding parameter group corresponding thereto The current uplink logical connection, the first determining device is further configured to:  - selecting, by the uplink packet coding parameter group pre-stored by the first type network device, an uplink space division coding parameter group different from the current uplink space division coding parameter group as a new current uplink space coding parameter group.  The uplink topology management device according to claim 31, further comprising:  a first parameter group obtaining device, configured to obtain an uplink space division coding parameter group respectively determined according to relative position information between the first type network device and each other network device in the vicinity, where each uplink acquired The space division coding group corresponds to an uplink logical connection starting from the first type of network device and pointing to the corresponding other network device;  a first saving device, configured to save the acquired uplink space division coding parameter group in association with a corresponding other network device;  The first determining device is further configured to:  - selecting an uplink space division coding parameter set previously saved in association with one other network device different from the current upstream potential peer device as the new current uplink space coding parameter group.  33. The uplink topology management apparatus according to claim 32, further comprising:  a first location information obtaining device, configured to obtain relative location information between the first type of network device and each of the other network devices in the vicinity; The first parameter group obtaining device is further configured to calculate an uplink space division coding parameter group according to the relative position information between the first type network device and each of the other network devices in the vicinity. The uplink topology management device according to claim 32 or 33, wherein the first saving device is further configured to: preset each of the acquired uplink space coding parameter groups with a preset An uplink logical topology information is stored in association, wherein each of the preset uplink logical topology information includes the first type network device and one or more first types at the same time Network devices are starting points and point to multiple uplink logical connections of their respective upstream potential peer devices,  The pre-set uplink logical topology information includes a current uplink logical topology information, which includes starting, by using the first type network device and the other one or more first type network devices respectively. Multiple current uplink logical connections to their respective current upstream potential peer devices;  The first determining apparatus is further configured to: select an uplink space coding parameter group that is previously saved in association with another uplink logic topology information different from the current uplink logic topology information, as the new current Upstream space division coding parameter group.  The uplink topology management device according to claim 32, wherein the mesh network comprises a mesh access network and/or a mesh infrastructure network, wherein when the mesh network is a mesh When accessing the network, the uplink topology management device further includes:  a first detecting device, configured to detect whether it is in a relatively slow motion or a relatively static state between itself and each other network device in the vicinity;  a first deleting device, configured to associate with the one or more other network devices before deleting, when detecting that it is not in a relatively slow motion or a relatively stationary state with one or more other network devices in the vicinity The saved uplink space coding parameter group.  36. The uplink topology management device according to claim 27, further comprising:  a second location information obtaining device, configured to obtain relative location information between the first type of network device and one or more other network devices in the vicinity;  The first determining device is further configured to, according to the obtained relative location information between the network device and other nearby network devices, acquire the new uplink space coding parameters in cooperation with the other one or more first type network devices. Group The new uplink space coding parameter group corresponding to the first type network device corresponds to An upstream logical connection starting from the first type of network device and pointing to another other network device different from its current upstream potential peer device.  37. The uplink topology management apparatus according to claim 31 or 36, wherein the space division coding comprises space division multiplexing coding and space division multiple access coding.  38. The uplink topology management apparatus according to claim 37, wherein the space division multiplexing coding comprises precoding, and the space division multiple access coding comprises beamforming coding.  The uplink topology management device according to claim 31 or 36, wherein the antenna array is an adaptive antenna array.  40. A downlink topology management apparatus for downlink logical topology management in a first type of network device of a mesh network, wherein the first type of network device has an antenna array and/or one or more a directional antenna, the antenna array or one of the directional antennas determines a current downlink logical connection starting from the first type of network device and directed to its current downstream potential peer device, where the downlink topology management device includes:  a second determining device, configured to determine whether the predetermined condition is satisfied;  a second determining means, configured to determine, according to the antenna array or the one or more directional antennas, a new downlink logical connection starting from the first type of network device when a predetermined condition is met,  The new downlink logical connection points to a new downlink potential peer device different from the current downlink potential peer device.  The downstream topology management apparatus according to claim 40, wherein the second determining means is configured to: when any one of the following conditions is satisfied, determine that the predetermined condition satisfies:  - a predetermined length of time has elapsed since the first type of network device last determined a new downlink logical connection;  - the load of the current downlink potential communication peer of the first type of network device exceeds a predetermined threshold;  - When the first type of network device randomly determines whether a new downlink logical connection needs to be determined, a determination result indicating that a new downlink logical connection needs to be determined is obtained. 42. The downstream topology management apparatus according to claim 40 or 41, wherein The first type of network device has a plurality of directional directivity antennas, each of the directional directional antennas pointing to one of the other network devices in the vicinity of the first type of network device, wherein the one or more of the directional directivity antennas Determining a current downlink logical connection starting from the first type of network device and pointing to its current downstream potential peer device,  The second determining means is further configured to select one or more directional directivity antennas from the remaining directional directivity antennas, wherein the selected one or more directional directivity antennas determine the new downlink logical connection.  The downlink topology management device according to claim 40 or 41, wherein the first type of network device has a variable directivity antenna, and the current orientation of the variable directivity antenna is determined. The second determining device includes: the first type of the network device as the starting point and the current downlink logical connection of the current downlink potential peer device.  a second pointing determining device, configured to determine a new pointing direction for the variable directivity antenna;  And a second pointing adjustment device, configured to adjust the variable directivity antenna to point to the new pointing, and the adjusted variable directivity antenna determines the new downlink logical connection.  The downlink topology management device according to claim 40, wherein the first type of network device has an antenna array, and the antenna array is determined based on a current downlink spatial coding parameter group corresponding thereto The current downlink logical connection,  The second determining apparatus is further configured to: select, by the downlink type coding parameter group prestored by the first type network device, a downlink space division coding parameter group different from the current downlink space division coding parameter group. As a new current downlink space division coding parameter set.  The downstream topology management device according to claim 44, further comprising:  a second parameter group obtaining device, configured to obtain a downlink space coding parameter group respectively determined according to relative position information between the first type network device and each of the other network devices in the vicinity, where each acquired downlink The space division coding group corresponds to a downlink logical connection starting from the first type network device and pointing to the corresponding other network device; a second saving device, configured to acquire the obtained downlink space coding parameter group and corresponding other Network devices are saved in association;  The second determining apparatus is further configured to: select, as a new current downlink space coding parameter group, a downlink space division coding parameter group previously saved in association with one other network device different from the current downlink potential peer device. .  The downlink topology management device according to claim 45, further comprising:  a third location information obtaining device, configured to obtain relative location information between the first type of network device and each of the other network devices in the vicinity;  The second parameter group obtaining means is further configured to calculate a downlink space division coding parameter group according to the relative position information between the first type network device and each of the other network devices in the vicinity.  The downlink topology management device according to claim 45 or 46, wherein the first saving device is further configured to: set each of the acquired downlink space coding parameter groups with a preset One downlink logic topology information is stored in association, wherein each of the preset downlink logic topology information includes the first type network device and one or more first types at the same time Network devices are starting points and point to multiple downstream logical connections of their respective downstream potential peer devices,  The each of the preset downlink logical topology information includes a current downlink logical topology information, which includes starting with the first type network device and the other one or more first type network devices respectively. Multiple current downlink logical connections to their respective current downstream potential peer devices;  The second determining apparatus is further configured to: select, as the new current, a downlink spatial coding parameter group that is previously saved in association with another downlink logical topology information different from the current downlink logical topology information. Downstream spatial coding parameter group.  The downlink topology management device according to claim 45, wherein the mesh network comprises a mesh access network and/or a mesh infrastructure network, wherein when the mesh network is a mesh When the network is connected to the network, the downlink topology management device further includes: a second detecting device, configured to detect whether it is in a relatively slow motion or a relatively static state between itself and each other network device in the vicinity; a second deleting device, configured to associate with the one or more other network devices before deleting, when detecting that it is not in a relatively slow motion or a relatively stationary state with one or more other network devices in the vicinity The saved downlink space coding parameter group.  49. The downlink topology management apparatus according to claim 40, further comprising:  a fourth location information obtaining device, configured to obtain relative location information between the first type of network device and one or more other network devices in the vicinity;  The second determining device is further configured to, according to the obtained relative location information with other network devices in the vicinity, cooperate with the other one or more first type network devices to acquire respective new downlink space coding parameters. Group  The new downlink space division coding parameter group acquired by the first type network device corresponds to the downlink of the first type network device and points to another network device different from the current downlink potential peer device. Logical connection.  50. The downlink topology management apparatus according to claim 44 or 49, wherein the space division coding comprises space division multiplexing coding and space division multiple access coding.  51. The downlink topology management apparatus according to claim 50, wherein the space division multiplexing coding comprises precoding, and the space division multiple access coding comprises beamforming coding.  The downlink topology management device according to claim 44 or 49, wherein the antenna array is an adaptive antenna array.  53. A first type of network device in a mesh network, wherein the first type of network device has an antenna array and/or one or more directional antennas, comprising: according to any one of claims 27 to 39 The uplink topology management apparatus for uplink logical topology management and/or the downlink topology management apparatus for downlink logical topology management according to any one of claims 40 to 52.