WO2011144018A1 - Communication method and device supporting low speed user terminals - Google Patents

Abstract

The present invention discloses a method and device supporting a large number of low speed user terminals. The method includes allocating different monitoring periods for each pre-divided user group, wherein said user group include at least one user terminal; allocating air interface resource to the user terminals of the user group in the current monitoring period; performing data transmission with the user terminals of the user group in the current monitoring period through said air interface resource. The embodiments of the present invention allocate the system resource in groups to the user terminals of each group according to time multiplex manner, through dividing a large number user terminals into groups. Thereby the utilization efficiency of the system resource is improved; providing service for even larger number of user terminals is supported; and processing load and energy consumption of the user terminals is reduced.

Description

 Communication method and device supporting low rate user terminal

 This application claims the priority of the Chinese Patent Application entitled "A Communication Method and Apparatus for Supporting Low-Rate User Terminals", which is filed on May 18, 2010, in the Chinese Patent Office, Application No. 201010176811. This is incorporated herein by reference. TECHNICAL FIELD The present invention relates to the field of wireless communication technologies, and in particular, to a communication method and apparatus for supporting a low rate user terminal. BACKGROUND In a mobile communication system using OFDMA (Orthogonal Frequency Division Multiplexing), for each user terminal, whether it is a normal user terminal or a low-rate user terminal, a resource assignment message must be sent to notify it. Use the corresponding air interface resources, such as business resources and control resources. When the number of user terminals in the system is gradually increased, the system needs to send a large number of assigned resource messages to notify the user terminal of the corresponding air interface resources, and in order to maintain the communication quality with the user terminal, the system also needs to allocate a large amount of channel resources to the user terminal for the user. The terminal performs channel measurement and reports measurement results, thereby consuming a large amount of system overhead.

 In the prior art, the design capacity of each cell in different communication systems is different, and generally supports simultaneous services for a few to several tens of up to a hundred user terminals. For example, one carrier fan in the GSM system can be 7 at the same time. -8 user terminal services, one carrier fan in CDMA system can serve 20-30 user terminals at the same time. One carrier fan in WCDMA system can serve 50-60 user terminals at the same time, 10M bandwidth WiMAX system One of the carrier fans can serve 80-120 or so user terminals at the same time. In a 10M bandwidth LTE system, one carrier fan can also serve 80-120 or so user terminals at the same time. In addition, the rate of user terminals that can be supported in different communication systems is also different. For example, the peak downlink rate of a user terminal in a CDMA system can reach 3.1 Mbps, and the average transmission rate of each user terminal is about 100 Kbps; The peak downlink rate of a user terminal can reach 384Kbps, and the average transmission rate of each user terminal is about 50Kbps. The peak downlink rate of a user terminal in the HSDPA version of the WCDMA system can reach 14.4Mbps, and the average transmission rate of each user terminal. Can reach about 1Mbps. Thus, the cells of existing communication systems are designed for relatively small user terminal capacity and relatively high data rates, primarily to meet the needs of human mobile voice communications and mobile data services.

When applying current mobile communication systems to communication between low-rate user terminals, such as M2M (Machine to When the machine, machine to machine communication, the inventor found that when there are a large number of low-rate user terminals in the current mobile communication system, the overhead of the system is too large, the resource utilization efficiency is low, and the design capability of the system cannot be fully utilized. Reduces the number of user terminals that the system can accommodate at the same time. Summary of the invention

 The embodiments of the present invention provide a communication method and apparatus for supporting a low-rate user terminal, so as to solve the problem that the existing system has a large overhead and restricts the number of user terminals.

 To this end, the embodiment of the present invention adopts the following technical solutions: A communication method for supporting a low-rate user terminal, including:

 Assigning different listening periods to the pre-assigned individual user groups, the user group including at least one user terminal; allocating air interface resources to the user terminals in the user group in the current listening period;

 Data transmission is performed by the air interface resource and the user terminal in the user group in the current listening period.

 A communication device supporting a low rate user terminal, comprising:

 a monitoring period allocating unit, configured to allocate different listening periods to each of the pre-assigned user groups, where the user group includes at least one user terminal;

 a resource assignment unit, configured to allocate air interface resources to user terminals in the user group in the current listening period; and a data transmission unit, configured to perform data transmission by using the air interface resource and the user terminal in the user group in the current listening period.

 It can be seen that, in the embodiment of the present invention, a large number of user terminals are grouped, and system resources are allocated to user terminals of each user group in a time-multiplexed manner, thereby improving system resource utilization efficiency, supporting providing services for a larger number of user terminals, and reducing Processing load and energy consumption of the user terminal. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a flowchart of a communication method supporting a large number of low-rate user terminals according to an embodiment of the present invention;

2 is a schematic diagram of a communication device supporting a large number of low-rate user terminals according to an embodiment of the present invention. The embodiment of the invention provides a communication method and device for supporting a low-rate user terminal, and the method or device can meet the communication requirements of a low-rate user terminal, and does not modify the physical structure such as the channel structure of the existing mobile communication system. Under the premise of layer technology, the overhead of the system can be reduced. Referring to FIG. 1, a flowchart of a communication method for supporting a large number of low-rate user terminals according to an embodiment of the present invention includes the following steps:

 S101: assign a different listening period to each of the pre-assigned user groups, where the user group includes at least one user terminal;

 S102: Allocating air interface resources to the user terminals in the user group in the current listening period, and specifically, allocating the air interface resources by using the assignment message;

 S103: Perform data transmission by using the air interface resource with a user terminal in a user group that is in a current listening period. It can be seen that, in the embodiment of the present invention, a large number of user terminals are divided into user groups, and communication is performed with user terminals in different user groups in different listening periods, that is, system resources are allocated to each user group in a time-multiplexed manner. The user terminal improves the utilization efficiency of system resources, supports providing services for a larger number of user terminals, and reduces processing load and energy consumption of the user terminals.

 It should be noted that the embodiments of the present invention are applicable to various low-rate communication systems, in addition to the M2M system, a system for communicating with humans and a system for communicating with humans, as long as the user terminal in the system requires speed. The capacity of the entire system is not particularly high.

 There are multiple implementations of step S102:

 (1) single assignment

 By default, the base station sends an assignment message allocation air interface resource for each user terminal in the user group.

(2) Group assignment

 In order to save bandwidth, the embodiment of the present invention specifically provides that the base station can configure the air interface resource by means of a "group assignment". The so-called group assignment means that an assignment message is sent to each user group, and in the assignment message, the specific Specifically, the air interface resource allocated to each user terminal in the group is specifically determined by using a group index + user terminal identifier to allocate air interface resources allocated to each user terminal, and the user terminal determines by using the group index and the user terminal identifier. Air interface resources allocated for itself. If the air interface resource is to be allocated to the user terminal by using the group assignment method, the base station sends the packet information to the user terminal through the air interface signaling after grouping the terminal. At this time, the base station can distinguish each user group by the group number.

 In addition, preferably, the foregoing assignment message may also be sent to the user terminal in each user group in a bitmap manner. In the default order, each user terminal knows its location and resource size in the entire resource block. The way to effectively reduce the overhead of assigning messages.

In addition, in the default or the normal situation, the assignment messages in the above two implementation manners are all instant assignment messages, that is, immediate and effective, and one assignment message only allocates a certain resource of the corresponding frame to the user once, the user terminal only at After receiving the assignment message, the resource allocated by the base station to the user terminal may be occupied, and the resource is not used by the user terminal in the next cycle, and the assignment message needs to be additionally sent.

 In order to avoid the bandwidth occupation caused by the multiple transmission of the assignment message, the embodiment of the present invention also proposes a manner of "continuous assignment", that is, by agreeing with the user terminal, the assignment message continues for multiple allocation periods. Effective, for example, the air interface resource assigned to the message can last for several cycles. This situation is common in mobile communications; for example, voice service or VoIP service, one voice packet is sent every 20ms, and when two people talk, the average person Each time of speaking is 500ms or more, so from a system perspective, it can allocate a resource every 20ms (5ms for one frame, that is, 4 frames), and allocate 25 times continuously, that is, for more than 500ms; The number of allocated resources and the length of the period can be carried in the assignment message or agreed by the protocol.

 Specifically, the instant assignment message is valid within an agreed time period or the number of allocated air interface resources expires, that is, the persistent assignment message is directed to a user terminal, indicating a group or a series of resources. The way of distribution. Specifically, the base station notifies the terminal to allocate the length of the period of the message by using the field of the appointment period or the time period of the assignment message. As the premise, if the user terminal is to be allocated resources by means of the group assignment method, the base station should notify the user terminal of the packet information through the air interface signaling at the same time as the grouping. At this time, the base station can distinguish each user terminal by the group number. group.

 The meaning of persistent assignment is that an assignment message can be assigned to air interface resources of multiple periods, and the manner of assigning messages relative to the instant can save the overhead of assigning messages. Specifically, the system may allocate a certain resource of a certain frame to a certain user, and then specify that the user uses the resource fixedly every 10 frames, for a total of 10 times; thus, starting from the current assigned frame, assuming the current frame number At 100, the assignment message indicates that the user can use the 100, 110, 120, 130, 140, 150, 160, 170, 180, 190 frames of the resource. A set or a string of resources is represented by the length of the assignment period carried in the persistent assignment message, which is generally the number of assigned resources.

 Through the group assignment or / and continuous assignment described above, the number of assigned messages can be effectively reduced, thereby further saving bandwidth resources.

 The following is a detailed introduction to the scheme with a specific example.

 1) The base station divides the user terminal into different user groups, and each user group includes at least one user terminal.

 The base station can flexibly divide the user terminal into the corresponding user group according to the time sequence of the user terminal accessing the system, the wireless environment information, the user terminal capability information, and the self-load situation of the base station system. The size and number of user groups are flexibly determined based on the system load, the number of currently accessed user terminals, and the capacity specifications of the maximum number of user terminals that the system is prepared to support.

The division of the user terminal into the corresponding user group is mainly performed by the base station, and the base station itself records the information of the user group. That is, since all resources are uniformly allocated to the user terminal by the base station, it is generally not necessary to notify the user terminal. For the default common assignment mode, the base station can distinguish the user groups and notify each user terminal by setting time-multiplexed Sleep sleep cycle parameters for user terminals of different user groups; each group has different monitoring periods, one for each group. The sleep parameters of the user terminals in the user group are the same. For the group assignment mode, since the user terminal has received the packet information (including the packet number) sent by the base station, the base station can distinguish by the group number (Group No). The user terminal group notifies that each user terminal group distinguishes the user terminal by a group index or a user terminal identifier.

 For example, a cell in a system needs to support 5000 user terminals, and the user terminals can be divided into 100 groups, and each user group has 50 user terminals;

 Each group can be defined by a group number of 0-99; each user group can also be distinguished by defining a sleep period parameter, for example, assuming that the system 5ms is a frame, and 10s=2000 frames are an allocation period, each user The group uses a 20 frame listening/available period in the allocation period, and the other 99 groups time multiplexes the resources in the current allocation period.

 2) The base station allocates different listening periods for each user group, allocates air interface resources to the user terminals in the user group through the assignment message, and performs data transmission with the user terminal by using the air interface resources allocated for the user terminal.

 During the time when the system allocates resources to other groups, the user terminal in each user group can maintain the status monitoring system message or listen to other cells of the system, or enter the sleep state without interacting with the system, thereby saving Energy consumption.

 The base station allocates air interface resources to the user terminal by sending the assignment message, and the resources used by different user groups are multiplexed in time, and the user terminal of each user group can only use the resources allocated by the system to the user at a specific time; The periodic mode or event mode allocates resources for user terminals of each user group.

 For the understanding of time multiplexing, the following is exemplified by a single assignment: Assume that each user group uses 20 frame resources, a total of 100 groups, then 0-19 frame resources are used in group 0, and 20-39 frame resources are in 1 group is used; and so on; since the assignment message only describes which user terminals the resources of the current frame are allocated, from the perspective of the air interface assignment message, the resources of 20 frames per cycle are time-multiplexed by such groups. Or shared use.

 After allocating the air interface resources, the base station can use the air interface resources allocated for the user terminal to perform data transmission with the air interface resources. In addition, the embodiment of the present invention further provides a communication device that supports a low-rate user terminal. Specifically, the device may be a base station device, or may be a functional entity located inside the base station, and may be combined by software, hardware, or software and hardware. The way to achieve.

Referring to Figure 2, the device includes: The monitoring period allocating unit 201 is configured to allocate different listening periods for each user group that is pre-allocated, and the user group includes at least one user terminal;

 The resource assignment unit 202 is configured to allocate air interface resources to the user terminal in the current listening period. The data transmission unit 203 is configured to perform data transmission by using the air interface resource with the user terminal in the user group in the current listening period.

 Optionally, the foregoing apparatus may further include: a grouping unit, configured to divide the user terminal according to a time sequence of the user terminal accessing the system, wireless environment information, user terminal capability information, or/and a service QoS requirement information of the user terminal Go to the corresponding user group.

 Optionally, the foregoing resource assignment unit 202 may further include:

 a first resource assignment unit, configured to send an assignment message allocation air interface resource to each user terminal; or a second resource assignment unit, configured to separately send an assignment message allocation air interface resource to each group;

 The assignment message is valid for immediate or continuous appointment time.

 Embodiments of the present invention are applicable to mobile communication systems employing 0FDMA technology, such as WiMAX, LTE FDD systems, LTE TDD systems, and subsequent evolution systems of these systems.

 In summary, the embodiment of the present invention allocates system resources to groups of user terminals in a time-multiplexed manner by grouping a large number of user terminals, thereby improving system resource utilization efficiency and supporting providing services for a larger number of user terminals. Reduce the processing load and energy consumption of the user terminal. In particular, bandwidth resources can be further saved by group assignment and/or continuous assignment.

 A person skilled in the art can understand that the process of implementing the method of the foregoing embodiment can be completed by hardware related to program instructions, and the program can be stored in a readable storage medium, and the program executes the above method when executed. Corresponding steps. The storage medium may be, for example, a ROM/RAM, a magnetic disk, an optical disk, or the like.

 The above description is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can also make several improvements and retouchings without departing from the principles of the present invention. It should be considered as the scope of protection of the present invention.

Claims

Rights request  A communication method for supporting a low-rate user terminal, comprising:  Assigning different listening periods to the pre-assigned individual user groups, the user group including at least one user terminal; allocating air interface resources to the user terminals in the user group in the current listening period;  Data transmission is performed by the air interface resource and the user terminal in the user group in the current listening period.  The method according to claim 1, wherein the allocating air interface resources to user terminals in the user group in the current listening period includes:  The air interface resource is allocated to the user terminal in the user group in the current listening period by the assignment message.  3. The method according to claim 1, wherein the method further comprises:  The user terminal is divided into corresponding user groups according to the time sequence of the user terminal accessing the system, the wireless environment information, the user terminal capability information, or/and the service QoS requirement information of the user terminal.  The method according to claim 2, wherein the assigning the air interface resource to the user terminal in the user group in the current listening period by using the assignment message is specifically:  Sending the assigned message allocation air interface resource to each user terminal in the user group in the current listening period; or sending the assignment message including the group index and the user terminal identifier to the user group in the current listening period, in the current listening period Each user terminal in the user group determines the air interface resource allocated for itself by the group index and the user terminal identifier.  The method according to claim 4, wherein the assignment message is an instant assignment message, and the instant assignment message only allocates the air interface resource to the user terminal for use once; or, the assignment The message continues to be valid until the assigned time of the assigned message or the allocated resource expires.  6. The method according to claim 4 or 5, further comprising:  When the assignment message is sent to the user terminal, indicating that the other user terminals other than the user terminal remain active or go to sleep; or  When a group assignment message is sent to each user group, the user terminal in other user groups other than the user group is instructed to remain active or enter a sleep state.  7. A communication device supporting a low-rate user terminal, comprising:  a monitoring period allocating unit, configured to allocate different listening periods to each of the pre-assigned user groups, where the user group includes at least one user terminal; a resource assignment unit, configured to allocate air interface resources to user terminals in a user group in a current listening period; a data transmission unit, configured to use the air interface resource and a user terminal in a user group in a current listening period Data transfer.  The device according to claim 7, wherein the communication device further comprises: a grouping unit, configured to: according to a time sequence of the user terminal accessing the system, wireless environment information, user terminal capability information, or/and a user The service QoS requirement information of the terminal divides the user terminal into corresponding user groups.  The device according to claim 7 or 8, wherein the resource assignment unit comprises: a first resource assignment unit, configured to send an assignment to each user terminal in a user group in a current listening period. Message allocation air interface resources; or  And a second resource assignment unit, configured to send an allocation message to the user group in the current listening period; the assignment message is valid for immediate effective or continuous appointment time.  A communication method for supporting a low-rate user terminal, comprising: a plurality of user groups, each user group being assigned a different listening period, each user group including at least one user terminal;  The user terminal in the user group in the current listening period receives the air interface resource allocated by the base station;  The user terminal in the user group of the current listening period performs data transmission with the base station through the air interface resource.  The method according to claim 10, wherein the user terminal in the user group in the current listening period receives the air interface resources allocated by the base station, including:  The user terminal in the user group in the current listening period receives the air interface resource allocated by the base station through the assignment message.  12. The method according to claim 10, wherein the method further comprises:  The user terminal is divided into corresponding user groups according to the time sequence of the user terminal accessing the system, the wireless environment information, the user terminal capability information, or/and the service QoS requirement information of the user terminal.  The method according to claim 11, wherein the user terminal in the user group in the current listening period receives the air interface resource allocated by the base station through the assignment message, which is specifically:  The user terminal in the user group in the current listening period obtains the allocated air interface resource by using the assignment message sent by the base station; or the user terminal in the user group in the current listening period receives the assignment message sent by the base station, the assignment message The user terminal in the user group in the current listening period determines the air interface resource allocated by the user terminal through the group index and the user terminal identifier. The method according to claim 13, wherein the assignment message is an immediate assignment message, and the instant assignment message only allocates the air interface resource to the user terminal for use once; or, the assignment The message continues to be valid until the assigned time of the assigned message or the allocated resource expires. A terminal, wherein the terminal belongs to one of a plurality of user groups, and each of the plurality of user groups is assigned a different listening period, and the terminal includes:  a first unit, configured to: when the user group to which the terminal belongs is in a current listening period, receive the air interface resource allocated by the base station;  And a second unit, configured to perform data transmission with the base station by using the air interface resource when the user group to which the terminal belongs is in a current listening period.  The terminal according to claim 15, wherein the first unit is configured to: when the user group to which the terminal belongs is in the current listening period, receive the air interface resource allocated by the base station by using the assignment message.  The terminal according to claim 16, wherein the first unit comprises:  The third unit is configured to: when the user group to which the terminal belongs is in the current listening period, receive an assignment message sent by the base station, where the assignment message includes an indication message of the group index and the user terminal identifier;  And a fourth unit, configured to determine, by using a group index and a user terminal identifier in the assignment message, an air resource allocated for itself.