CN103517278B - Access the competing method of public frequency band - Google Patents

Abstract

The invention provides a competition method for accessing public frequency band. The method of the present invention is applied to the scenario where the first type of user equipment and the second type of user equipment within the coverage area of the wireless access device compete to access the public frequency band, first determine the first type of user equipment and the second type of user equipment based on the backoff mechanism The back-off time for the user equipment of the second type to access the public frequency band, wherein the back-off time is an integer multiple of at least one time slot; then, determine the second time based on the network service quality of the user equipment of the first type a priority for a type of user equipment to access the public frequency band, and adjust the backoff time of the first type of user equipment based on the priority, so as to avoid that the backoff time of the first type of user equipment differs from that of the second type of user equipment The backoff time of the user equipment creates contention conflicts. It can be seen that, in the present invention, the length of the adjusted backoff time is adjusted so that the user equipment of the first type does not generate contention conflicts with the user equipment of the second type.

Description

Competing approaches to access common frequency bands

technical field

The invention relates to a competition method, in particular to a competition method for accessing public frequency bands.

Background technique

D2D (Device to Device) communication is a novel direct communication technology between terminals applied in the cellular system, which allows mobile terminals to use the licensed frequency band of the cellular network for point-to-point communication under the control of the cellular network. D2D communication has gradually become a research hotspot in the field of wireless communication due to its advantages such as reducing terminal transmit power, prolonging battery life, enhancing multicast and broadcast transmission rates, and improving system spectrum efficiency.

However, as spectrum resources become increasingly scarce, communication technologies based on LTE standards that can work in shared frequency bands (such as ISM frequency bands) are receiving more and more attention. The use of LTE communication technology in the ISM frequency band can bring the following benefits: 1) Provide a new market for future communication systems based on LTE technology; 2) Provide additional capacity for cellular communication; 3) Generate new applications and communication solutions (eg wireless D2D communication using LTE technology).

In order to enable the LTE D2D system to work in the ISM frequency band, the main challenge comes from the coexistence of LTE D2D communication and WLAN communication based on IEEE 802.11 series standards. Since WLAN communication using the ISM frequency band has been widely deployed at present, it is very likely that LTE D2D communication and a certain WLAN communication will be deployed in the same area at the same time and compete for the use of the same frequency resource. However, the existing LTE standard obviously cannot be applied to this kind of competition, so the most intuitive and effective method is to use the same media access mechanism (such as CSMA/CA mechanism) for D2D communication as WLAN users.

However, although the media access mechanism can effectively coordinate and manage the use of wireless channels by WLAN user equipment, this mechanism cannot coordinate the resource competition between multiple types of user equipment (such as LTE D2D user equipment and WLAN user equipment), and Once a large number of user equipments (for example, including D2D communication pairs and WLAN users) compete for the same frequency resource, serious contention conflicts will result. Specifically, when the back-off counters of the D2D user equipment pair and the WLAN user equipment decrease to zero at the same time, contention conflicts will occur between the two user equipments, which will result in increased communication delay and decreased frequency band utilization.

Since WLAN communication using the ISM frequency band has been widely deployed, it is very likely that an LTE user equipment and a certain WLAN user equipment will be deployed in a same area at the same time and compete to use the same frequency resource.

Therefore, in order to enable LTE D2D communication to efficiently work in the ISM frequency band, it is necessary to optimize the radio resource management scheme in the existing LTE user equipment (such as: staggering the access channel time of each system and the way of grouping D2D communication pairs) and Redesign.

Contents of the invention

In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a competition method for accessing a common frequency band, so as to reduce competition conflicts between two types of user equipments in the common frequency band.

In order to achieve the above object and other related objects, the present invention provides a competition method for accessing the public frequency band, which is applied to the first type of user equipment and the second type of user equipment within the coverage area of the wireless access device to compete for access to the public frequency band The scenario includes: 1) determining the back-off time for the user equipment of the first type and the user equipment of the second type to access the common frequency band based on a back-off mechanism, wherein the back-off time is an integer of at least one time slot 2) Determine the priority of the first type of user equipment to access the public frequency band based on the network service quality of the first type of user equipment, and adjust the priority of the first type of user equipment based on the priority backoff time, so as to avoid conflicts between the backoff time of the user equipment of the first type and the backoff time of the user equipment of the second type.

Preferably, the step 2) includes: shortening the backoff time based on the network quality of service of the first type of user equipment being better than a preset network quality of service; based on the network quality of service of the first type of user equipment The back-off time is extended if it is worse than the preset network service quality; wherein, the back-off time after adjustment and the back-off time before adjustment are within a time slot range.

Preferably, the method further includes: A) grouping all the user equipments of the first type based on the number of the user equipments of the first type within the coverage of the wireless access device exceeding a first threshold; B) determining, based on the number of groups, the offset of the starting moment of the back-off time for each user equipment of the first type in each group to access the public frequency band.

Preferably, in the step A), the method of detecting the number of the first type of user equipment within the coverage of the wireless access device includes: based on the wireless access device allocated to all the first Determine the number of the first type of user equipment within the coverage of the wireless access device by using the identification information of the user equipment of the same type.

Preferably, the method of grouping all the first-type user equipments in the step A) includes: grouping all the first-type user equipments based on the priority of each of the first-type user equipments , so that the priority of each user equipment of the first type in each group is balanced.

Preferably, the step B) further includes: dividing a time slot into time periods greater than the number of groups, and determining the first time slot in each group based on the time periods and the number of groups An offset of the start moment of the back-off time for accessing the common frequency band by the similar user equipment, wherein each of the offsets is different.

Preferably, the step 2) further includes: adjusting the starting moment of the back-off time for the user equipment of the first type in the corresponding group to access the public frequency band based on the offset.

Preferably, the method further includes: based on that the number of the first type of user equipment within the range exceeds the first threshold, and the number of the first type of user equipment is different from the number of the second type of user equipment If the ratio of the numbers exceeds the second threshold, the priorities of some of the first-type user equipments for accessing the public frequency band are adjusted.

Preferably, the step 2) further includes: adjusting the backoff time based on the adjusted priority of the user equipment of the first type.

As mentioned above, the competition method for accessing the public frequency band of the present invention has the following beneficial effects: the length of the adjusted backoff time is adjusted by obtaining the priority of the first type of user equipment, so that the first type of user equipment There is no contention conflict with the second type of user equipment; in addition, when the wireless access device detects that the number of the first type of user equipment exceeds a first threshold, group the first type of user equipment , and adjust the offset of the backoff time based on the grouping, so as to change the starting moment of the backoff time of the first type of user equipment, so as to reduce the competition between the first type of user equipment and the second type of user equipment Conflict: adjusting the length of the backoff time on the basis of changing the starting moment of the backoff time of the first type of user equipment can further reduce the problem of contention conflict between the first type of user equipment and the second type of user equipment .

Description of drawings

FIG. 1 is a flow chart of the competition method for accessing public frequency bands of the present invention.

FIG. 2 is a flow chart of a preferred solution of the competition method for accessing public frequency bands of the present invention.

FIG. 3 is a schematic diagram showing the structure of the wireless access equipment covering the first type of user equipment and the second type of user equipment in the competition method for accessing the public frequency band according to the present invention.

FIG. 4 is a schematic diagram of an embodiment of adjusting backoff time in the contention method for accessing a public frequency band according to the present invention.

FIG. 5 is a schematic diagram of another embodiment of adjusting backoff time in the contention method for accessing a common frequency band according to the present invention.

FIG. 6 is a schematic diagram of another embodiment of adjusting backoff time in the contention method for accessing a public frequency band according to the present invention.

Component designation description

1 Wireless access device

2 Class I user equipment

3 Second class user equipment

S1~S2, S1’~S5’ steps

Detailed ways

Embodiments of the present invention are described below through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes, and various modifications or changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present invention.

Embodiment one

FIG. 1 is a flowchart of a competition method for accessing public frequency bands according to the present invention. The competition method for accessing the public frequency band is applied to a scenario where the user equipment of the first type and the user equipment of the second type within the coverage of the wireless access device compete for access to the public frequency band. The competition method in this embodiment is mainly performed by a first competition system, and the first competition system is an application module or the like installed in the first type of user equipment. The first type of user equipment is a modern intelligent electronic device that can automatically and quickly perform a large number of numerical calculations and various information processing according to a pre-stored program. Its hardware includes but is not limited to: PDA, set-top box, embedded device Wait. Preferably, the first type of user equipment is a device for direct communication between devices, for example, a mobile phone. The second type of user equipment is an intelligent electronic device with a communication mode different from that of the first type of user equipment, and its hardware includes but not limited to: PDA, set-top box, embedded device, etc. Preferably, the second type of user equipment is a device that uses the wireless access device for communication, for example, a notebook computer and the like.

In step S1, the first competition system determines a backoff time for the user equipment of the first type and the user equipment of the second type to access the common frequency band based on a backoff mechanism, wherein the backoff time is at least one hour Integer multiples of the gap. Wherein, the public frequency band includes any frequency band that enables the first type of user equipment and/or the second type of user equipment to communicate based on network protocols, including but not limited to the ISM frequency band (industrial, scientific and medical frequency band) Wait. The backoff mechanism includes, but is not limited to: a random backoff mechanism, an adaptive backoff mechanism, and the like.

It should be noted that those skilled in the art should understand that the manner of determining the backoff time for the user equipment of the first type to access the public frequency band based on the backoff mechanism will not be described in detail here.

For example, the first contention system obtains time slots and the number of time slots for the user equipment of the first type and the user equipment of the second type to access the common frequency band based on a random backoff mechanism, and based on the time slot and the The back-off time for each of the user equipment of the first type and the user equipment of the second type to access the common frequency band is obtained by using the product of the number of time slots.

In step S2, the first competition system determines the priority of the first type of user equipment to access the public frequency band based on the network service quality of the first type of user equipment, and adjusts the priority based on the priority The back-off time of the user equipment of the first type is used to avoid competition and conflict between the back-off time of the user equipment of the first type and the back-off time of the user equipment of the second type. Wherein, the network service quality includes any index representing the network service, including but not limited to: network delay, network congestion, network throughput, packet loss rate, and the like.

The manner in which the first competition system determines the priority of the first type of user equipment to access the public frequency band based on the quality of service of the network where the first type of user equipment is located includes but is not limited to:

1) Determining a priority for the first type of user equipment to access the public frequency band based on a network quality of service of the first type of user equipment. For example, if the network quality of service obtained by the first type of user equipment only includes a network delay of 50 ms, then the first competition system determines that the first type The user equipment has a low priority for accessing the public frequency band.

2) First obtain the evaluation value of the network service quality based on the multiple network service qualities of the first type of user equipment, and then determine the access of the first type of user equipment based on the evaluation value of the network service quality. The priority of the public frequency band. For example, the network service quality of the first type of user equipment obtained by the first competition system includes: network delay 50 ms, network jitter 30 ms, the preset weight of network delay is 1, and the weight of network jitter is 2, Then the first competition system first obtains the evaluation value of the service quality of the mobile network where the user equipment of the first type is located is 1*50+2*30=110, and then based on the evaluation value being less than the preset evaluation value of 150 , to determine that the priority of the user equipment of the first type to access the public frequency band is high.

Specifically, the manner in which the first competition system adjusts the backoff time based on the priority includes step S21.

In step S21, the first competition system shortens the backoff time based on the network quality of service of the first type of user equipment being better than a preset network quality of service; based on the network quality of service of the first type of user equipment The back-off time is extended if it is worse than the preset network service quality; wherein, the back-off time after adjustment and the back-off time before adjustment are within a time slot range.

For example, if the first competition system determines that the priority of the user equipment of the first type to access the public frequency band is high, the first competition system shortens the backoff time by half a time slot length, so that all The user equipment of the first type accesses the common channel prior to the user equipment of the second type having a contention conflict with it.

In another example, the first competition system determines that the priority of the user equipment of the first type to access the public frequency band is low, then the first competition system extends the backoff time by half a time slot length, so that The first type of user equipment accesses the common channel before the second type of user equipment after detecting the next DIFS time.

Embodiment two

As shown in FIG. 2, the competition method is jointly executed by the first competition system and the second competition system. The second competing system is an application module or the like installed in the wireless access device. The wireless access device is a modern intelligent electronic device that can automatically and quickly perform a large number of numerical calculations and various information processing according to a pre-stored program, and can communicate with all networks covered by the wireless access device The user equipment communicates, and its hardware includes but not limited to: wireless gateway, wireless router, wireless bridge, etc.

In step S1', the first competition system determines the priority of accessing the public frequency band for the first type of user equipment based on the network service quality of the first type of user equipment, and provides the priority to to the wireless access device.

It should be noted that those skilled in the art should understand that the above method of determining the priority of the first type of user equipment to access the public frequency band based on the network service quality of the first type of user equipment is the same as that in the aforementioned step S1 Determining that the priority of accessing the public frequency band by the first type of user equipment is the same or similar based on the network service quality of the first type of user equipment, which will not be repeated here.

The first contention system sends the priority to the wireless access device.

For example, the first contention system sends the network access request including the priority to the wireless access device.

In step S2', the second competition system groups all the user equipments of the first type based on the number of the user equipments of the first type within the coverage of the wireless access device exceeding a first threshold .

Specifically, the method for the second competition system to determine the number of the first type of user equipment within the coverage of the wireless access device includes step S21'.

In step S21', the second competition system determines the user equipment of the first type within the coverage of the wireless access device based on the identification information assigned by the wireless access device to all the user equipments of the first type. The number of user devices. Wherein, the identification information includes any information allocated by the wireless access device, including but not limited to: IP address. Preferably, there are two user equipments of the first type in each group.

For example, as shown in FIG. 3, the wireless access device allocates an IP address to the first type of user equipment based on a network access request from the first type of user equipment, and the second competition system allocates an IP address based on the assigned The number of IP addresses of the first type of user equipment is used to determine the number of the first type of user equipment within the coverage of the wireless access device.

The manner in which the second competition system groups all the user equipments of the first type includes but is not limited to: random grouping.

Preferably, the second competition system groups all the first-type user equipments based on the priority of each of the first-type user equipments, so that each of the first-type user equipments in each group Balanced priorities.

Specifically, each of the user equipments of the first type provides their respective priorities to the second competition system, and the second competition system assigns the obtained first priority A type of user equipment is grouped together, and the remaining user equipment of the first type is grouped.

For example, the priorities of all first-type user equipment acquired by the second competition system include: the priority of the first-type user equipment A1 is high, the priority of the first-type user equipment A2 is high, and the priority of the first-type user equipment is high. If the priority of the device A3 is low, the second competition system groups the first-type user equipment A1 and the first-type user equipment A3 into one group, and divides the first-type user equipment A2 into one group.

In step S3', the second contention system determines the offset of the start time of the back-off time for each user equipment of the first type in each group to access the public frequency band based on the number of groups.

Specifically, the second contention system increments the offset of each packet sequentially by a preset time period.

For example, group 1 includes: first-type user equipment B1, first-type user equipment B2;

Group 2 includes: first-type user equipment B3, first-type user equipment B4;

The preset time period is t, then the second competition system sets the time period of group 1 as t, and the time period of group 2 as 2t, and sends the time period t to the first type of user equipment B1 and the first type of user equipment The user equipment B2 sends the time period 2t to the first-type user equipment B3 and the first-type user equipment B4.

Preferably, the step S3' also includes a step S31'.

In step S31', the second contention system divides a time slot into time periods greater than the number of groups, and determines the first time slot in each group based on the time periods and the number of groups An offset of a start time of a backoff time for a type of user equipment to access the public frequency band, wherein each of the offsets is different.

For example, the second competition system divides the acquired user equipment of the first type into three groups, and the duration of one time slot is T _slot , and the second competition system divides a time slot equally based on the number of groups to determine that the time period is T _slot /4, then the second competition system determines that the offset of the first group is T _slot /4 based on the time period and the number of groups. The offset of the second group is 2T _slot /4, and the offset of the third group is 3T _slot /4. Then, the offset of each group is sent to each first-type user equipment of the corresponding group.

It should be noted that the above method of dividing the duration of a time slot into equal parts is only an example. In fact, any division of a time slot into time periods greater than the number of groups, and determining each time period based on the time period The method of offsetting the starting moment of the backoff time for each user equipment of the first type in the group to access the public frequency band is included within the scope of the present invention.

Next, in step S4', the first competition system adjusts the starting moment of the backoff time for the user equipment of the first type in the corresponding group to access the public frequency band based on the offset.

For example, as shown in FIG. 4, the offset of the start time of the backoff time obtained by the first competition system is T _slot /4, then the first competition system will originally start timing the backoff time at time t3 The time is delayed by T _slot /4 duration, that is, the first competing system starts timing the back-off time for the user equipment of the first type to access the public frequency band at time t3'.

As another example, as shown in FIG. 5, the offset of the start time of the backoff time obtained by the first competition system is 2T _slot /4, then the first competition system will start timing the time at time t5. The start time of the backoff time is advanced by 2T _slot /4 duration, that is, the first competing system starts timing the backoff time for the user equipment of the first type to access the public frequency band at time t5'.

In step S5', the first competition system adjusts the backoff time of the first type of user equipment based on the priority determined in step S1', so as to avoid the backoff time of the first type of user equipment from the The back-off time of the second type of user equipment generates contention conflicts.

It should be noted that those skilled in the art should understand that the above method of adjusting the back-off time of the first type of user equipment based on the determined priority of the first type of user equipment to access the public frequency band is the same as the foregoing The method of adjusting the backoff time of the first type of user equipment based on the determined priority of the first type of user equipment for accessing the public frequency band in step S2 is the same or similar, and will not be described in detail here.

For example, as shown in FIG. 6, the first contention system connects the user equipment of the first type to the start time of the backoff time based on the obtained offset 2T _slot /4 of the start time of the backoff time. The time is advanced from t6 to t6', and then, based on the determined priority being high, the first contention system shortens the backoff time by 1/5 time slot, so that the end time of the backoff time is t7.

On the basis of Embodiment 2, in this embodiment, the second competition system of the present invention further executes step SA (not shown), and the first competition system executes step SB (not shown).

In step SA, the second competition system is based on the fact that the number of user equipments of the first type within the range exceeds the first threshold, and the number of user equipments of the first type is different from the number of user equipments of the second type If the ratio of the numbers exceeds the second threshold, the priorities of some of the first-type user equipments for accessing the public frequency band are adjusted.

Specifically, the second competition system will allow some of the first-type user equipment to access The priority of the public frequency band is adjusted to be high; the second competition system based on the ratio of the number of the first type of user equipment to the number of the second type of user equipment is lower than the preset ratio B, then partly The priority of accessing the public frequency band by the user equipment of the first type is adjusted to be low, so that user equipments in each network compete fairly for the public frequency band.

For example, the second competition system detects that the number of user equipments of the second type is 25, and the number of user equipments of the first type is 50, of which 30 user equipments of the first type access all If the priority of the public frequency band is high and the others are low, then the second competition system is based on the fact that the ratio of the number of the first type of user equipment to the number of the second type of user equipment is greater than a preset threshold of 1.5, then The second competition system adjusts the priority of 15 user equipments of the first type with high priority to low, so that user equipments in each network compete fairly for the public frequency band.

It should be noted that those skilled in the art should understand that the above method of adjusting the priority of some user equipments to access the public frequency band is only an example. In fact, any preset The method of determining the priority of adjusting part of the user equipments to access the public frequency band based on the number of proportions is included in the scope of the present invention.

In another example, the number of user equipments of the second type detected by the second competition system is 50, the number of user equipments of the first type is 10, and 3 of the user equipments of the first type The priority of the 7 user equipments of the first type is low, the sum of the throughputs of the user equipments of the second type obtained by the second competition system is 20M, the first type The sum of the throughputs of the user equipments is 30M, then the second competition system adjusts the priorities of the four user equipments of the first type to be high based on the ratio of the throughputs.

The second contention system sends the adjusted priority to the corresponding user equipment of the first type.

Next, in step SB, when the priority of the user equipment of the first type obtained by the first competition system does not match the priority determined based on the quality of service of the network where the user equipment of the first type is located, the The first contention system adjusts the backoff time based on the adjusted priority of the user equipment of the first type.

It should be noted that, the above method of adjusting the backoff time based on the adjusted priority of the first type of user equipment based on the first type of user equipment is the same as the method of adjusting the backoff time based on the first type of user equipment in the foregoing step S5'. The way of adjusting the backoff time is the same or similar to the priority determined by the quality of service of the network, which will not be described in detail here.

To sum up, in the competition method for accessing the first type of user equipment to the public frequency band described in the present invention, the length of the adjusted backoff time is adjusted by obtaining the priority of the first type of user equipment, so that all The user equipment of the first type does not generate a contention conflict with the user equipment of the second type; in addition, when the wireless access device detects that the number of user equipment of the first type exceeds a first threshold, the user equipment of the second type One type of user equipment is grouped, and the offset of the backoff time is adjusted based on the grouping, so as to change the starting moment of the backoff time of the first type of user equipment, so that the difference between the first type of user equipment and the second type can be reduced. Competition conflict between user equipments; adjusting the length of the backoff time on the basis of changing the start time of the backoff time of the first type of user equipment can further reduce the distance between the first type of user equipment and the second type of user equipment problem of competing conflicts. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial application value.

The above-mentioned embodiments only illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed in the present invention should still be covered by the claims of the present invention.

Claims (8)

1. A kind of 1. competing method for accessing public frequency band, applied to the first kind user in radio reception device institute coverage The scene of equipment and the second class user equipment contention access public frequency band, it is characterised in that the competing method includes：

   1) determine that the first kind user equipment and the second class user equipment access the public frequency band based on avoidance mechanism Back off time, wherein, the back off time for time slot at least one integral multiple；

   2) determine that the first kind user equipment accesses the public affairs based on the network service quality of the first kind user equipment With the priority of frequency range, and the back off time of the first kind user equipment is adjusted based on the priority, to avoid described the The back off time of a kind of user equipment produces competition with the back off time of the second class user equipment and conflicts；Wherein, based on institute The network service quality for stating first kind user equipment is better than default network service quality, between keeping out of the way described in shortening；Based on described The network service quality of first kind user equipment is inferior to default network service quality, extends the back off time；Wherein, adjust The back off time afterwards is with the back off time before adjustment in a slot range.
2. 2. the competing method of access public frequency band according to claim 1, it is characterised in that the method further includes：

   A the quantity) based on the first kind user equipment in radio reception device institute coverage exceedes first threshold When, all first kind user equipmenies are grouped；

   B) packet-based quantity determines that each first kind user equipment accesses the public frequency band in each packet The offset of the initial time of back off time.
3. 3. it is according to claim 2 access public frequency band competing method, it is characterised in that in the step A) in detecting The mode of the quantity of the first kind user equipment in radio reception device institute coverage includes：

   The identification information that all first kind user equipmenies are distributed to based on the radio reception device is described wireless to determine The quantity of the first kind user equipment in access device institute coverage.
4. 4. it is according to claim 2 access public frequency band competing method, it is characterised in that in the step A) in institute There is the mode that the first kind user equipment is grouped to include：

   All first kind user equipmenies are grouped based on the priority of first kind user equipment each described, with Make the priority of each first kind user equipment in each group balanced.
5. 5. the competing method of access public frequency band according to claim 2, it is characterised in that the step B) further include：

   By a time slot dividing into the period more than the number of packet, and the number based on the period and the packet Measure to determine that the first kind user equipment in each packet accesses the initial time of the back off time of the public frequency band Offset, wherein, each offset is different.
6. 6. the competing method of access public frequency band according to claim 5, it is characterised in that the step 2) further includes：

   The first kind user equipment adjusted based on the offset in respective packets accesses when keeping out of the way of the public frequency band Between initial time.
7. 7. the competing method of access public frequency band according to claim 2, it is characterised in that the method further includes：

   Quantity based on the first kind user equipment in the scope exceedes the first threshold and the first kind user The quantity of equipment and the ratio of the quantity of the second class user equipment exceed second threshold, first kind user described in adjustment member Equipment accesses the priority of the public frequency band.
8. 8. the competing method of access public frequency band according to claim 7, it is characterised in that the step 2) further includes： Priority based on the first kind user equipment after adjustment adjusts the back off time.