WO2010009600A1

WO2010009600A1 - Resource configuration method for multimedia broadcast and multicast service

Info

Publication number: WO2010009600A1
Application number: PCT/CN2008/073696
Authority: WO
Inventors: 苟伟; 王斌; 马子江; 毕峰
Original assignee: 中兴通讯股份有限公司
Priority date: 2008-07-23
Filing date: 2008-12-24
Publication date: 2010-01-28
Also published as: CN101635881A; CN101635881B

Abstract

A resource configuration method for a multimedia broadcast and multicast service MBMS, comprises: at least two resource allocation schemes, a base station comparing the resource allocation schemes and selecting the scheme that has a lower signaling overhead and that can achieve the allocation to implement the service resource configuration. The MBMS resource configuration method can significantly reduce the overhead to utilize each scheme separately, and as such the overall overhead can be reduced.

Description

Multimedia broadcast and multicast service resource configuration method

Technical field

The present invention relates to a Long Term Evolution (LTE) system, and more particularly to a method for configuring a Multimedia Broadcast Multicast Service (MBMS) resource in a hybrid carrier system.

Background technique

With the rapid development of the Internet and the popularity of large-screen multi-function mobile phones, a large number of mobile data multimedia services and various high-bandwidth multimedia services have emerged, such as video conferencing, television broadcasting, video on demand, advertising, online education, interactive games, and the like. This aspect meets the rising business needs of mobile users and brings new business growth points to mobile operators. These mobile data multimedia services require multiple users to receive the same data at the same time, and have the characteristics of large data volume, long duration, and delay sensitivity compared with general data services.

In order to effectively utilize mobile network resources, 3rd Generation Partnership Project ( 3rd Generation

The Partnership Project (3GPP) proposes MBMS, which is a technology that transmits data from one data source to multiple targets, realizes the sharing of resources (including core network and access network), and improves network resources ( Especially the utilization of air interface resources). The 3GPP-defined MBMS not only enables plain text low-rate message-like multicast and broadcast, but also enables high-speed multimedia services to broadcast and multicast, providing a variety of rich video, audio and multimedia services, which undoubtedly conforms to future mobile The trend of data development provides a better business prospect for the development of 3G.

The transmission of the MBMS service on the air interface is divided into a dedicated carrier and a shared carrier. The main difference between the two transmission modes is as follows: In the dedicated carrier mode, the carrier only carries the MBMS service. In the hybrid carrier mode, the carrier carries not only the MBMS service but also the non-MBMS (unicast unicast) service. In this way, in the process of carrying the MBMS service in the hybrid carrier mode, there are two types of services in which the same carrier is multiplexed. How to make the two types of services do not interfere with each other and play the most important role in the transmission business process has always been a key topic in the industry discussion. In the process of carrying the MBMS service and the non-MBMS service using the hybrid carrier, the multiplexing of the two types of services is Frequency-Division Multiplexing (FDM) and Time-Division Multiplexing (referred to as Time-Division Multiplexing). For TDM) and FDM/TDM hybrid multiplexing. At present, the industry uses TDM as the main reuse method for research. In the following description, TDM is also used as a multiplexing mode of hybrid carrier MBMS service and non-MBMS service.

In the process of TDM multiplexing, the MBMS service and the non-MBMS service need to take into account the influence of various factors, including: the impact on the unicast service delay, the user equipment (User Equipment, UE for short), power saving, over-provisioning (over Allocation ) , scheduling granularity, system overhead, and scheduling flexibility. Currently, multicast sub-frame configuration is implemented using the Two-level (two-level) method. The Two-level method uses two levels of parameters to define the specific location that indicates the MBMS service subframe is carried. As shown in Figure 1, the details are as follows:

Wireless frame level configuration (macro level): Indicates the specific location of the radio frame containing the multicast sub-frame in the system; Sub-frame level configuration (micro level): Indicates that in the radio frame containing the multicast sub-frame, The location where the sub-frame is played.

Currently, there are two industry-recognized methods for implementing multicast subframe configuration using a two-level system, but each has its own advantages and disadvantages. Both methods use 320ms as the modification period of the multicast subframe configuration according to the scheduling granularity requirements, as follows:

Option A:

Use two levels of parameters to define the location of a specific subframe that indicates the MBMS service is carried, as follows:

1. Wireless frame level (macro level) is implemented using parameters N and M:

* Parameter N, discrete allocation with 2 ^W radio frames as the period, the first radio frame of each period is used as the radio frame containing the multicast sub-frame, and the value of N is implemented by using 3 bits;

· Parameter M, using the parameter M to implement the offset indication of the different MBMS areas in the radio frame level configuration, to avoid the MCH (Multicast Channel) interference caused by the overlap of different MBMS areas, and the value of the Μ uses 3 bits Way of achieving 2. Sub-frame configuration (micro level) is implemented in 3 bits. The 3-bit specific size indicates the number of consecutive sub-frames from sub-frame #1 (excluding #0, #4, and #5 sub-frames).

Option B:

1. The radio frame level (macro level) uses the parameter Q, and the value of Q is implemented in 32 bits. The 32 bit is used according to the bitmap (bit mapping) method to implement the indication of 32 radio frames in the 320 ms modification period. ;

2. Sub-frame configuration (micro level) is implemented in 3-bit mode. The 3-bit specific size indicates the number of consecutive sub-frames from sub-frame #1 (excluding #0, #4, and #5 sub-frames).

The above two methods have found a corresponding balance between system overhead and configuration flexibility. In general, the greater the system overhead, the higher the flexibility; on the contrary, the smaller the system overhead, the lower the flexibility. In general, the system overhead of using scheme A is small, but the corresponding flexibility is also low. It is even possible that resources in some overlapping areas of MBMS cannot be allocated, resulting in the inability of the service to carry or severely waste resources. In addition, the scheme A may be multiplied in the MBMS overlap area due to the limitation of the configuration method, so that this method cannot be used normally in the MBMS overlap area. Scheme B uses a 32-bit bitmap method, which makes scheduling flexibility higher. However, it is obvious that the 32-bit system overhead is larger in the solution, and the system information load brought to the system is also larger.

Summary of the invention

The technical problem to be solved by the present invention is to provide a multimedia broadcast and multicast service resource allocation method, which overcomes the defects caused by the separate use of the foregoing scheme A and scheme B, so that the radio frame level configuration has high flexibility and low overhead.

In order to solve the above problem, the present invention provides a multimedia broadcast and multicast service MBMS resource configuration method, where the MBMS service resource allocation method includes at least two resource allocation schemes, and the base station compares the resource allocation schemes, and selects signaling. The overhead is small, and the allocated solution can be implemented for service resource configuration. Further, the above method may also have the following features:

The base station determines whether it is currently an overlapping coverage area, and if so, the degree of overlap, and calculates the signaling overhead in the overlapping area of each MBMS service resource allocation scheme according to the degree of overlap;

The base station selection signaling overhead is small, and the allocated solution can be implemented for service resource configuration. Further, the above method may also have the following features:

The degree of statistical overlap of the base station refers to: the number of the base station statistics that belong to different MBMS service areas at the same time.

Further, the above method may also have the following features:

The resource allocation scheme includes scheme A and scheme B,

The scheme A uses two levels of parameters to indicate the location of a specific subframe that carries the MBMS service, including:

(A1) The radio frame level is implemented using parameters N and M:

(A1.1) The parameter N is discretely allocated in a period of 2 ^W radio frames, and the first radio frame in each period is used as a radio frame including a multicast sub-frame, and the value of N is implemented by using a 3-bit method;

(A1.2) Parameter M, 参数 Use parameter M to realize the offset indication of different MBMS areas in the radio frame level configuration, and the value of M is implemented in 3 bits;

(A2) The subframe configuration is implemented in a 3-bit manner, and the 3-bit specific size indicates that the number of consecutive subframes other than the #0, #4, and #5 subframes is removed from the subframe #1;

The scheme B uses two levels of parameters to indicate the location of a specific subframe that carries the MBMS service, including:

(B1) The radio frame level uses the parameter Q, and the value of Q is implemented in 32 bits; the 32 bit is used according to the bit mapping method to implement the indication of 32 radio frames in the 320 ms modification period;

(B2) The subframe configuration is implemented in a 3-bit manner. The 3-bit specific size indicates that the number of consecutive subframes outside the #0, #4, and #5 subframes is removed from subframe #1.

Further, the above method may also have the following features:

The base station separately calculates, according to the degree of overlap, each MBMS service resource allocation scheme overlaps The signaling overhead of the area includes:

When using scheme A, the base station has an overhead of 6 χ η bits at the radio frame allocation level;

When using the scheme, the base station has an overhead of 32 bits at the radio frame allocation level;

η is the number of different MBMS service areas that the base station belongs to at the same time.

Further, the above method may also have the following features:

When the number of base stations belonging to different MBMS service areas is less than 6, the scheme A is used preferentially. Otherwise, scheme B is used preferentially.

The method according to claim 4, wherein the scheme A is used preferentially when the base station does not belong to the overlapping coverage area.

Further, the above method may also have the following features:

The base station determines whether the allocation can be achieved according to the rationality of the allocation.

Further, the above method may also have the following features:

After the base station selects the resource allocation scheme, the MBMS resource allocation is sent according to the selected scheme. Further, the foregoing method may further have the following features:

The terminal receives the MBMS resource allocation instruction, knows which resource allocation scheme is used, and then receives and decodes the MBMS service and the non-MBMS service data sent by the base station according to the used resource allocation scheme.

The present invention effectively combines the advantages of several existing solutions, greatly reducing the overhead of each solution alone, and drastically reducing the overall overhead, especially when the overlap coverage is severe. Furthermore, the present invention does not add additional overhead and is simple to perform. BRIEF abstract

1 is a schematic diagram of a two-level multicast sub-frame configuration method in the prior art;

Figure 2 is a flow chart of an embodiment of the present invention;

FIG. 3 is a schematic diagram of overlapping coverage of different MBMS service areas according to an application example of the present invention. Preferred embodiment of the invention

The core idea of the present invention is: The MBMS service resource allocation method may be composed of two or more resource allocation schemes, and the resource allocation schemes may be switched; the base station selects appropriate resources according to the signaling overhead, whether the allocation is possible, and the like. Distribution plan.

Specifically, the base station side selection signaling overhead is small, and the allocated MBMS service resource allocation scheme can be implemented, and the terminal side receives the corresponding MBMS resource allocation instruction according to the protocol, and interprets the signaling content to obtain the final instruction content.

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

The base station side can select an appropriate resource allocation scheme and perform handover according to whether overlap occurs, degree of overlap, signaling overhead, allocation flexibility, and whether allocation can be realized. As shown in Figure 2, an embodiment of the invention includes the following steps:

Step 201, the base station determines whether it is currently an overlapping coverage area, and if so, proceeds to the next step, and if not, proceeds to step 204;

Step 202: The base station counts the degree of overlap, that is, the base station belongs to several different MBMS service areas at the same time;

For example, the base station can belong to two different MBMS service areas at the same time, or can belong to six different MBMS service areas at the same time;

Step 203: Calculate signaling overhead.

For example, if the base station belongs to two different MBMS service areas, if the scheme A is used, the overhead at the radio frame allocation level is 6 x 2 = 12 bits. If scheme B is used, the overhead at the radio frame allocation level is 32 bits; The signaling overhead of scheme A is smaller than the signaling overhead of scheme B. If the base station belongs to n (n 6 ) or more different MBMS service areas at the same time, if scheme A is used, the overhead at the radio frame allocation level is 6 xn ≥ 36 bits. If the scheme B is used, the overhead is always 32 bits at the radio frame allocation level. In this case, the instruction overhead of the scheme A is greater than the instruction overhead of the scheme B. Step 204, the scheme with a small signaling overhead is preferentially selected;

If the base station does not belong to the overlapping coverage area, it is obvious that the signaling overhead of the scheme A is smaller than the signaling overhead of the scheme B, that is, the priority selection scheme A; Step 205, determining whether the allocation can be implemented, if yes, performing step 206, otherwise, performing the step

207;

The base station can determine whether the allocation can be achieved according to the rationality of the allocation, and the flexibility of the allocation scheme affects whether the scheme can be allocated: because the MBMS service resource allocation is reasonably allocated with the non-MBMS service (for example, the unicast service), Because the priority of multicast services is usually high, it may occupy a large number of MBMS resources, causing non-MBMS services to fail to communicate normally. However, reasonable adjustments to multicast services, such as changing the location of multicast subframes, can take into account various MBMSs. Service; Because Solution A can provide low allocation flexibility, in some cases there is a problem that cannot be allocated, and Scheme B has a very high degree of flexibility. The base station should consider the solution after considering it. Step 206: Select The above signaling overhead is small, step 208 is performed;

Step 207: Select a solution that can implement allocation, and the signaling overhead is relatively small, that is, the selected scheme is larger than the scheme signaling overhead in step 204, but the flexibility is high, and the allocation can be implemented.

Step 208: The base station sends an MBMS resource allocation instruction according to the selected scheme.

Step 209: The terminal receives the corresponding MBMS resource allocation instruction, interprets the signaling content, and knows which allocation scheme is used, and then receives and decodes the MBMS service and the non-MBMS service data sent by the base station according to the used allocation scheme.

Of course, the terminal side can also use other methods to know what scheme the base station uses now. For example, the instruction formed by the scheme A can be placed on the SIB2 (the SIB is the System Information Block), and the instruction formed by the scheme B is placed. Send on SIB3 and so on.

In order to further explain the use of the present invention, some application examples are described below. For the convenience of description, it is assumed that there are 8 different MBMS service areas, and they overlap only in a certain area F, and there is no overlapping coverage in other places. As shown in Figure 3, it is an overlap of the F areas by eight different MBMS service areas. The F-area is a geographical area in which there may be many base stations and at least one base station.

For the base station in the F area, the base station learns that there are 8 different single frequency network (SFN) areas overlapping and covering itself, so the base station first compares 釆 Which scheme has a small signaling overhead, and after comparison, the cost of the scheme B is small, and it is judged whether the scheme B can achieve the allocation, and the unicast service is circumvented (since the flexibility of the scheme B is the highest, the above two conditions are always established. , so use program B.

The base stations in the non-F area in the SFN1 area are independent, and there is no overlapping coverage. (The above is the overlap of the F area and other SFN areas in the SFN1 area. There is no overlapping coverage in other places.) For scenario A with less overhead, if the solution cannot achieve the allocation requirement (the flexibility of scenario A is low, there is the possibility that the allocation cannot be realized, and the possibility that the allocation cannot be realized in the general independent region is very small), then only the solution can be used. B. If scenario A can achieve allocation, then scenario A is used.

The base station in the non-F area in the SFN2-SFN8 area uses the same method as the base station in the SFN1 area. Similarly, the final scheme can be selected.

SFN1, SFN2 and SFN8 each have MBMS services. Then we use two schemes to independently allocate resources and calculate their respective instruction overheads.

The overhead of the radio frame level of the scheme A: the overhead of each base station in the F area is 6 x 8=48 bits, and the other non-overlapping areas are 6 8=48 bits, (for example, the overhead of the base station in the SFN1 area except the F area is 6 bits, The same is true for SFN2, which is 6bit in other regions. The total cost of scenario A is 48+48=96bit.

The overhead of the radio frame level of the scheme B: the overhead of each base station in the F area is 32 bits, and the other non-overlapping areas are 32 8=256 bits. (For example, the overhead of the base station except the F area in the SFN1 area is 32 bits, and the SFN2 is also the same. For 32bit, the same for other regions). The total cost of scenario B is 32+256=288bit.

The overhead of the radio frame level of the present invention is: the overhead of each base station in the F area is 32 bits, and the other non-overlapping areas are 6 8=48 bits, (for example, the overhead of the base station except the F area in the SFN1 area is 6 bits, SFN2 The same is true for 6bit, the same for other regions). The solution of the present invention is sold in a total of 32 + 48 = 80 bits.

It can be seen that the allocation overhead of the radio frame level of the present invention is the smallest, the overhead of the scheme B is the largest, and the cost of the scheme A is second.

As the degree of overlap coverage increases, the overhead of the method of the invention decreases rapidly. For example when overlapping When the coverage reaches 10 and 16 different MBMS service areas, the corresponding system overhead is shown in Table 1:

Table 1 MBMS resource allocation overhead table with overlapping coverage

The present invention effectively combines the two schemes, thereby obtaining the advantages of the two schemes, discarding the defects thereof, and thereby realizing the allocation of MBMS service resources in the LTE system. With this method, the radio frame level configuration can be made the most flexible and the overhead is minimized; and the signaling overhead of the resource allocation of the overlapping coverage area is minimized, and the signaling overhead of the resource allocation of the non-overlapping area is also minimized.

In the embodiment of the present invention, the method for selecting the option A or the solution B is used to determine a suitable resource allocation scheme. However, the present invention is not limited thereto, and may be extended to select two or more scenarios, and the base station side only needs to select a letter. The overhead is small, and the allocated MBMS service resource allocation scheme can be implemented.

While the invention has been described in connection with the specific embodiments, the modifications and variations may be Such modifications and variations are considered to be within the scope of the invention and the scope of the appended claims.

Industrial Applicability The present invention provides a method for configuring a multimedia broadcast and a multicast service resource. The base station compares at least two resource allocation schemes, selects a signaling overhead, and implements the allocated scheme for service resource configuration. The invention effectively combines the advantages of several existing solutions, greatly reduces the overhead of each solution alone, and greatly reduces the overall overhead, especially in overlapping coverage. When it is serious. Furthermore, the present invention does not add additional overhead and is simple to perform.

Claims

Claim

A MBMS resource allocation method for multimedia broadcast and multicast services, wherein the MBMS service resource allocation method includes at least two resource allocation schemes, and the base station compares the resource allocation schemes, and the selection signaling overhead is small. And can implement the allocated solution for business resource configuration.

The method according to claim 1, wherein the method specifically includes: the base station determining whether it is currently an overlapping coverage area, and if so, the degree of overlap, and calculating each MBMS service resource allocation scheme according to the degree of overlap. Signaling overhead in overlapping areas;

The base station selection signaling overhead is small, and the allocated solution can be implemented for service resource configuration.

The method according to claim 2, wherein the degree of statistical overlap of the base station is: The number of the base station statistics that belong to different MBMS service areas at the same time.

4. The method of claim 3, wherein the resource allocation scheme comprises a scheme A and a scheme B,

(A1) The radio frame level is implemented using parameters N and M:

(A1.1) The parameter N is discretely allocated with a period of 2 ^W radio frames, and the first radio frame of each period is used as a radio frame including a multicast sub-frame, and the value of N is implemented by using a 3-bit method; A1.2) The parameter M, the parameter M is used to implement the offset indication of the different MBMS areas in the radio frame level configuration, and the value of M is implemented by the 3 bit method;

The scheme B uses two-level parameters to indicate the location of a specific subframe that carries the MBMS service, including: (B1) the radio frame level uses the parameter Q, and the value of the Q is implemented by using a 32-bit method; the 32-bit is used according to the bit mapping manner. , used to achieve the indication function of 32 radio frames in the 320ms modification period; (B2) The subframe configuration is implemented in a 3-bit manner, and the 3-bit specific size indicates that the number of consecutive subframes outside the #0, #4, and #5 subframes is removed from the subframe #1.

The method according to claim 4, wherein the base station calculates the signaling overhead of each MBMS service resource allocation scheme in the overlapping area according to the degree of overlap, including:

When using scenario A, the base station has an overhead of 6 x n bits at the radio frame allocation level;

When using scheme B, the base station has an overhead of 32 bits at the radio frame allocation level;

n is the number of base stations that belong to different MBMS service areas at the same time.

The method according to claim 4, wherein, when the number of the MBMS service areas that belong to the different base stations is less than 6, the scheme A is used preferentially; otherwise, the scheme B is used preferentially.

7. The method according to claim 4, wherein scheme A is used preferentially when the base station does not belong to the overlapping coverage area.

The method according to claim 1 or 2, wherein the base station determines whether the allocation can be achieved based on the rationality of the allocation.

The method according to claim 2, wherein after the base station selects a resource allocation scheme, the MBMS resource allocation instruction is sent to the terminal according to the selected scheme.

The method according to claim 9, wherein the terminal receives the MBMS resource allocation instruction, knows which resource allocation scheme is used, and further receives and decodes the MBMS service sent by the base station and the non-MBMS according to the used resource allocation scheme. Business data.