WO2013138980A1

WO2013138980A1 - Resource allocation method, and distributed transmission method and device

Info

Publication number: WO2013138980A1
Application number: PCT/CN2012/072543
Authority: WO
Inventors: 张健; 张元涛; 张翼; 王轶; 周华
Original assignee: 富士通株式会社
Priority date: 2012-03-19
Filing date: 2012-03-19
Publication date: 2013-09-26

Abstract

Embodiments of the present invention provide a resource allocation method of an E-PDCCH, and a distributed transmission method and device. In an embodiment, the resource allocation method comprises: dividing an RE allocated to an E-PDCCH into multiple CCEs according to a preset size of a CCE; and allocating the remaining RE, which is less than one CCE, to the CCE according to a preset policy. The embodiments of the present invention solve the technical problem that resources are not fully utilized during resource allocation and distributed transmission of the E-PDCCH if a conventional PDCCH method is reused.

Description

Resource allocation method, distributed transmission method and device

The present invention relates to a control information transmission technology in a communication system, and more particularly to a resource allocation method, a distributed transmission method and apparatus for an enhanced physical downlink control channel in an LTE-A (LTE-Advanced, Enhanced Long Term Evolution) system . Background technique

The PDCCH (Physical Downlink Control CHannel) is the main channel used for carrying control information in the LTE (Long Term Evolution) R8/9/10. The base station transmits downlink scheduling to the user (UE, User Equipment). The allocation and uplink scheduling give equal control signaling, so that the user can know information such as resource allocation and transmission mode used for uplink and downlink transmission. The correct reception of the PDCCH is a prerequisite for successful demodulation of the data channel, so it plays an important role in system design.

In the LTE 8/9/10 standard, in the time domain, the PDCCH occupies the first M OFDM (Orthogonal Frequency Division Multiplexing) symbols per subframe, and the M value ranges from 1 to 4; In the frequency domain, the PDCCH is distributed to the entire system bandwidth. The PDCCH is used to carry downlink control information (DCI, Downlink Control Information), and the control channel element (CCE, Control Channel Element) is configured as a minimum unit. One PDCCH (DCI) may be composed of L CCEs, where each CCE includes 36. resource particles (RE, resource Element), L in the range of 1, 2, 4, 8, showing the degree of polymerization different from the PDCCH (aggregation level) ₀ of each CCE 9 and can be seen as RE groups (REG, RE Group), each REG contains 4 REs, and the REG size (4RE) is the smallest unit of PDCCH interleaving and resource mapping. To implement demodulation of the PDCCH, the user will perform a blind check on the PDCCH in a specific search space. A schematic diagram of a PDCCH search space is shown in FIG. 1. The PDCCH search space referred to herein includes a common search space and all user-specific (UE-specific) search spaces, and is used to indicate a location where all PDCCHs may appear.

Figure 1 assumes that the total number of REGs that the PDCCH region can accommodate is N _REe , so the total number of available REs it contains is 4N _REC , which can be divided into N: water CCE, and CCE "CCE _N constitutes the PDCCH search.

The cable space contains the locations where all PDCCHs may occur, and REs with less than 1 CCE will not be utilized by the PDCCH, which is labeled "unused RE" in Figure 1. The search space of Figure 1 actually represents the complex between PDCCHs. With the structure, the PDCCH with a degree of aggregation L can start at the CCE position numbered tiL (η=0,1,···), occupying consecutive L CCEs. According to the standard, the bit stream constituting CCE _Q ~ CCE _N is sequentially subjected to scrambling, QPSK (Quadature Phase Shift Keying) modulation, layer mapping, and SFBC (Space Frequency Block Code). Coding) Precoding operation, this series of operations does not change the logical relationship between CCEs in the search space, so the interleaving process of the latter PDCCH can still be described using the structure of FIG. Since the minimum unit involved in the interleaving in the standard is 4 REs, that is, the size of one REG, for convenience of presentation, the interleaving is considered as being performed in units of REG. Taking a specific antenna port as an example, the interleaving process of the PDCCH in units of REG is illustrated by FIG. 2.

As shown in FIG. 2, although the search space of the PDCCH does not occupy all N _REC REGs, the interleaving process is performed in all N _REC REG ranges, that is, the unused REs also participate in interleaving, and participate in determining the PDCCH interleaving. position. For the new REG sequence obtained after interleaving, it will be cyclically shifted according to the standard, and then mapped to the physical resource where the REG is located. The resource mapping of the PDCCH is performed in the form of the REG, in the form of the first-time and post-frequency. Figure 3 shows the PRB pair, the physical resource block pair (physical resource block pair) as an example, and the REG is given on the time-frequency resource. The way of dividing.

Figure 3 shows the REG position within a PRB pair. The left figure shows the REG position in the PDCCH, where the PDCCH occupies the first 3 OFDM symbols; the right picture shows the REG partition in the R-PDCCH (Relay PDCCH), which is the base station eNB and the relay node (Relay Node) Inter-control channel, which is transmitted in the legacy PDSCH region, and a single R-PDCCH cannot be mapped across slots, so Figure 3 shows the location of the REG in the first slot, the second slot is the same. Available. The division of the REG in the R-PDCCH is to support the R-PDCCH transmission of the interleaving mode. For the R-PDCCH in the interleaving mode, the processing module before the REG mapping mostly reuses the PDCCH structure described above, and is not repeated, and the DM-RS reference signal does not appear in the PRB pair where the R-PDCCH is located. Figure 3 shows the difference between R-PDCCH and PDCCH in REG mapping. For PDCCH and R-PDCCH, the number of REGs included in each PRB pair is always an integer. Finally, the PDCCH/R-PDCCH will perform multi-antenna transmission in SFBC mode.

For new scenarios such as heterogeneous networks, multi-point cooperation, and carrier aggregation that occur in LTE-A, traditional PDCCHs often face interference or capacity problems in applications. However, problems in the control channel will directly lead to data channel reception failure, so the control channel The enhancement is very necessary. Currently, the Enhanced Physical Downlink Control Channel (E-PDCCH, Enhanced PDCCH) has been incorporated into the standardization process of Release 11, and is under discussion and research. Unlike the PDCCH, the E-PDCCH is transmitted in the PDSCH region, which can alleviate the capacity problem on the one hand. Existing data channel enhancement techniques can also be utilized. In order to ensure the robustness of E-PDCCH transmission, a distributed transmission mode supporting E-PDCCH is also required. Distributed transmission means that the E-PDCCH needs to be distributed to multiple PRB pairs spaced apart from each other in frequency, which is in fact consistent with the design of the PDCCH transmission. Therefore, the E-PDCCH distributed transmission can reuse the transmission mode of the PDCCH, including CCE size, REG based interleaving, REG mapping, and SFBC transmission. However, the traditional PDCCH method directly applied to the E-PDCCH transmission may cause insufficient utilization of resources. FIG. 4 illustrates this problem by two examples.

Unlike the PDCCH, the E-PDCCH is not distributed to the entire system bandwidth, and only occupies several PRB pairs spaced apart from each other in frequency. FIG. 4 assumes that the E-PDCCH occupies four PRB pairs uniformly dispersed in the system bandwidth. For the 2-port CS (Cell-specific Reference Signal), 2-port DM-RS (demodulation reference symbol), 2-port CSI-RS (Channel State Information-Reference) in Figure 4 (1) Signal, channel state information reference signal) such a reference signal configuration, the number of REs that can be used in each PRB pair is 106, so the total number of REs available to the resources of the 4 PRBs allocated to the E-PDCCH is 106*4=424 According to the transmission rule of the PDCCH, REs smaller than one CCE size (36 REs) will not be utilized by the E-PDCCH, so 424 REs can accommodate 11 CCEs, and the remaining 28 are not used by the E-PDCCH. RE, the percentage of unused REs in total distributed transmission resources is 28/424=6.6%. In another example given in Figure 4 (2), the reference signal is configured as 4 CRS ports, 4 DM-RS ports, and 4 CSI-RS ports. Similarly, 4 PRB pairs can be used. The total number of REs is 88*4=352, which can accommodate 9 CCEs. The remaining 28 REs are not used by E-PDCCH. The percentage of unused REs in distributed distributed total resources is 28/352=8%. In the above example, 6.6% and 8% of REs are not used by the E-PDCCH, respectively. In addition, 28 REs are equivalent to 1/4 of a PRB pair in terms of magnitude, and such resource utilization is not ideal. Resources are underutilized. In fact, the traditional PDCCH and the R-PDCCH also have the same problem, that is, there are unused REs, but for the PDCCH, since the total system bandwidth is occupied, the total number of available REs is large, so the percentage of unused REs is not A high level of E-PDCCH is achieved; for the R-PDCCH, since the number of relay nodes is much smaller than the number of users in the E-PDCCH, the requirement for resource utilization is not as tight as the E-PDCCH. In summary, the reuse of the traditional PDCCH method in the E-PDCCH causes the problem that the resources allocated to the E-PDCCH cannot be fully utilized.

Another potential problem with reusing PDCCH policies in E-PDCCH distributed transmission is REG mapping. As described above, whether for the PDCCH or the R-PDCCH, one PRB pair can be divided into an integer number of REGs, and for the E-PDCCH, since there are multiple possibilities for the location of the reference signal, this will bring about the division of the REG. Some issues, Figure 5 illustrates this issue. Figure 5 (1) shows a schematic diagram of REG partitioning in the E-PDCCH region according to the conventional PDCCH scheme. For the OFDM symbol in which the CRS is located, the REG partition is not different from the PDCCH, but for the OFDM symbol in which the DM-RS is located, the conventional REG The division mode may cause the two REs constituting the SFBC transmission to be excessively spaced in frequency. For example, the two REs constituting the SFBC transmission labeled in Figure 5 (1) are separated by 5 REs, which is not conducive to SFBC demodulation. In addition, one PRB pair in Fig. 5 (1) cannot be divided into an integer number of REGs. In order to avoid SFBC spanning large frequency intervals, one method is to use STBC (Space Time Block Code) in the OFDM symbol in which the DM-RS/CSI-RS is located, and two adjacent STBCs (the same) The occupation of 4 REs is defined as one REG, as shown in Figure 5 (2), while other OFDM symbols still use the REG definition of the legacy PDCCH. In this way, the performance loss of the SFBC can be avoided, but whether the E-PDCCH resource can be divided into an integer number of REGs depends on the reference signal configuration and the number of PRB pairs allocated for the E-PDCCH. The root cause is that a PRB pair may not be able to be divided. Is an integer number of REGs. As shown in Figure 5 (2), the PRB pair cannot be divided into an integer number of REGs, and 2 unused REs remain.

It should be noted that the above description of the technical background is only for the purpose of facilitating the clear and complete description of the technical solutions of the present invention, and is convenient for understanding by those skilled in the art. The above technical solutions are not considered to be well known to those skilled in the art simply because these solutions are set forth in the background section of the present invention. Summary of the invention

An object of the embodiments of the present invention is to provide a resource allocation method, a distributed transmission method, and an apparatus for an enhanced physical downlink control channel in an LTE-A system, so as to overcome the technical problem of insufficient resource utilization caused by reusing the traditional PDCCH method. .

According to an aspect of the embodiments of the present invention, a resource allocation method for an enhanced physical downlink control channel is provided, where the method includes:

Dividing resource particles (RE) allocated to an enhanced physical downlink control channel (E-PDCCH) into a plurality of CCEs according to a predetermined size of a control channel particle (CCE);

According to a predetermined policy, the remaining REs of less than one CCE are allocated to the CCE.

According to another aspect of the embodiments of the present invention, a distributed transmission method of an E-PDCCH is provided, The method includes:

Dividing the RE allocated to the E-PDCCH into multiple CCEs according to a predetermined size of the CCE;

Allocating the remaining REs of less than one CCE to the CCE according to a predetermined policy;

The CCEs of the REs of the remaining less than one CCE are interleaved and resource mapped in units of pre-defined RE groups.

According to another aspect of the present invention, a base station is provided, where the base station includes: a dividing unit, which divides an RE allocated to an E-PDCCH into a plurality of CCEs according to a predetermined size of a CCE; It allocates the remaining REs of less than one CCE to the CCE according to a predetermined policy. According to another aspect of the embodiments of the present invention, a method for distributed transmission of an E-PDCCH is provided, where the method includes:

Allocating the RE allocated to the E-PDCCH for resource division;

The REs allocated to the E-PDCCH are interleaved and resource mapped in units of pre-defined RE groups; wherein the pre-defined RE groups include 2 REs for each RE group.

According to another aspect of the present invention, a base station is provided, where the base station includes: a dividing unit that performs resource division by using an RE allocated to an E-PDCCH;

a transmission unit that performs interleaving and resource mapping on REs allocated to the E-PDCCH in units of pre-defined RE groups;

The pre-defined RE group includes 2 REs for each RE group.

According to another aspect of the embodiments of the present invention, a resource allocation method for an E-PDCCH is provided, where the method includes:

The RE included in each physical resource block pair (PRB pair) allocated for the E-PDCCH is divided into a plurality of enhanced control channel particles (E-CCE) according to a predetermined policy with two adjacent REs as a minimum unit.

According to another aspect of the embodiments of the present invention, a method for distributed transmission of an E-PDCCH is provided, where the method includes:

Each of the PRBs allocated to the E-PDCCH is divided into a plurality of E-CCEs according to a predetermined policy by using two adjacent REs as a minimum unit;

Interleaving and resource mapping of REs included in each PRB pair allocated to the E-PDCCH in units of pre-defined RE groups, or in units of the E-CCE;

The pre-defined RE group includes 2 REs for each RE group. According to another aspect of the present invention, a base station is provided, where the base station includes: a dividing unit that uses two adjacent REs as a minimum unit, and allocates each of the E-PDCCHs according to a predetermined policy. The PRB divides the included RE into multiple E-CCEs.

According to another aspect of the present invention, a computer readable program is provided, wherein, when the program is executed in a base station, the program causes a computer to perform the foregoing resource allocation method of the E-PDCCH in the base station; Alternatively, the program causes the computer to perform the aforementioned distributed transmission method of the E-PDCCH in the base station.

According to another aspect of the present invention, a storage medium storing a computer readable program, wherein the computer readable program causes a computer to perform the foregoing resource allocation method of the E-PDCCH in a base station, or the foregoing A distributed transmission method of E-PDCCH.

The beneficial effects of the embodiments of the present invention are as follows: the resource partitioning method and the distributed transmission method in the embodiment of the present invention overcome the method of dividing the RE resources allocated to the E-PDCCH according to the traditional resource partitioning method of the PDCCH. The resulting resources exploit inadequate technical issues.

Specific embodiments of the present invention are disclosed in detail with reference to the following description and the accompanying drawings, which illustrate the manner in which the principles of the invention can be employed. It should be understood that the embodiments of the invention are not limited in scope. The embodiments of the present invention include many variations, modifications, and equivalents within the spirit and scope of the appended claims.

Features described and/or illustrated with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, in combination with, or in place of, features in other embodiments. .

It should be emphasized that the term "comprising" or "comprising" is used to mean the presence of a feature, component, step or component, but does not exclude the presence or addition of one or more other features, components, steps or components. DRAWINGS

Many aspects of the invention can be better understood with reference to the following drawings. The components in the figures are not drawn to scale, but only to illustrate the principles of the invention. In order to facilitate the illustration and description of some parts of the invention, the corresponding parts in the figures may be enlarged or reduced. Elements and features described in one of the figures or one embodiment of the invention may be combined with elements and features illustrated in one or more other figures or embodiments. In the accompanying drawings, like reference numerals refer to the In the drawing: 1 is a schematic diagram of a PDCCH search space;

2 is a schematic diagram of a PDCCH interleaving process;

Figure 3 is a schematic diagram of REG resource division;

4 is a schematic diagram of E-PDCCH resources in different reference signal configurations;

Figure 5 is a schematic diagram of REG resource division;

6 is a flowchart of a resource allocation method of an E-PDCCH according to an embodiment of the present invention;

7 is a flowchart of a distributed transmission method of an E-PDCCH according to an embodiment of the present invention;

Figure 8 is a schematic diagram of redistribution of unused REs;

9 is a schematic diagram of an interleaving process of an E-PDCCH;

10 is a schematic diagram of resource and reference signal configuration of an E-PDCCH;

Figure 11 is a schematic diagram of the formation process of E-CCE (k = 4) _;

12 is a schematic diagram of E-REG resource mapping;

Figure 13 is a schematic diagram of the formation process of E-CCE (k = 2) _;

14 is a schematic structural diagram of a base station according to an embodiment of the present invention;

15 is a flowchart of a distributed transmission method of an E-PDCCH according to another embodiment of the present invention; FIG. 16 is a schematic diagram of a base station according to another embodiment of the present invention;

17 is a flowchart of a resource allocation method of an E-PDCCH according to another embodiment of the present invention;

18 is a flowchart of a distributed transmission method of an E-PDCCH according to another embodiment of the present invention; FIG. 19 is a schematic diagram of an existing E-CCE division;

20 is a schematic diagram of E-CCE multiplexing according to an embodiment of the present invention;

21 is a schematic diagram of an E-CCE search space;

22 is a schematic diagram of an E-CCE interleaving process;

23 is a schematic diagram of E-CCE multiplexing according to another embodiment of the present invention;

Figure 24 is a schematic diagram of an E-CCE search space;

Figure 25 is a block diagram showing the composition of a base station according to another embodiment of the present invention. detailed description

The foregoing and other features of the embodiments of the invention will be apparent from the These embodiments are merely exemplary and are not limiting of the invention. In order to enable those skilled in the art to accommodate The embodiments of the present invention are exemplified by the resource allocation method and the distributed transmission method of the E-PDCCH in the LTE-A system, but it can be understood that the embodiment of the present invention is not Limited to the above system, it is applicable to other systems involving PDCCH allocation and transmission.

Example 1

The embodiment of the invention provides a resource allocation method for an E-PDCCH. Figure 6 is a flow chart of the method, please refer to Figure 6, the method includes:

Step 601: Divide the RE allocated to the E-PDCCH into multiple CCEs according to a predetermined size of the CCE. Step 602: Assign the remaining REs of less than one CCE to the CCE according to a predetermined policy. In this embodiment, the predetermined size of the CCE is generally 36 REs. For the available RE resources allocated to the E-PDCCH, when the conventional PDCCH method is reused, the REs of less than one CCE will not be utilized, and the embodiment of the present invention will This part of the unused RE is reassigned to the CCE for use. In fact, the most flexible allocation method is which CCEs are assigned to REs, and the number of REs allocated by each CCE is informed to the user, but such flexible RE allocation is not necessary from the perspective of notification overhead and search space requirements.

In this embodiment, after the REs allocated to the E-PDCCH are divided according to the predetermined size (36 REs) of the CCE, the remaining REs of less than one CCE (also referred to as unused in the following description) RE), reassign it to several CCEs, making these CCEs exceed the size limit of 36 REs.

In one embodiment, the unused REs may be first divided into groups, each group including a predetermined number of REs, and then each group of REs is assigned to at least one CCE according to a predetermined policy. If there are REs that are not grouped in this part of the unused RE, then this part of the RE that cannot be grouped is assigned to a CCE according to the principle of resource division. In this embodiment, the predetermined number is an even number, for example, 2 or 4, that is, the unused REs are divided into groups, each group including 2 REs or 4 REs. In this embodiment, the predetermined policy is, for example, first assigning to the even-numbered CCEs according to the cyclic shifting manner, and then allocating to the odd-numbered CCEs; or, according to the cyclic shifting manner, first assigning the odd-numbered CCEs. , and then assigned to the even-numbered CCE; or, to the CCE of the specified number. The predetermined policy may be other methods as long as the unused RE can be reassigned to the CCE, and the embodiment is not limited thereto.

In another embodiment, the unused REs may be first divided into multiple groups of multiple sizes, and then each group of REs is allocated to one CCE according to a predetermined policy, wherein the number of REs of each size is It is even. For example, an unused RE is divided into multiple groups of two sizes, one size is 2 REs, and the other size is 4 REs, and then each group of REs is assigned to one CCE according to a predetermined policy. For example, follow the loop In the bit mode, a group of 2 REs is assigned to an odd-numbered CCE, and a group of 4 REs is assigned to an even-numbered CCE. The above is only an example, and the embodiment is not limited thereto.

The method in this embodiment is applicable to the transmission of the user search space of the E-PDCCH, and is also applicable to the transmission of the common search space of the E-PDCCH.

The method of the embodiment of the present invention is applicable to control information transmission using SFBC.

With the method of the present embodiment, the technical problem of insufficient resource utilization caused when the RE resources allocated to the E-PDCCH are allocated according to the traditional PDCCH resource division method is overcome.

Example 2

The embodiment of the invention further provides a distributed transmission method of an E-PDCCH. Figure 7 is a flow chart of the method, please refer to Figure 7, the method includes:

Step 701: The RE that is allocated to the E-PDCCH is divided into multiple CCEs according to the predetermined size of the CCE. Step 702: Allocate the remaining REs of less than one CCE to the CCE according to a predetermined policy. Step 703: The defined RE group is a unit, and performs interleaving and resource mapping on CCEs that allocate the remaining REs of less than one CCE.

In one embodiment, the pre-defined RE group contains 2 REs for each RE group, and step 703 performs interleaving and resource mapping for CCEs that have allocated unused REs in units of 2 REs.

In this embodiment, the steps 701 and 703 can be implemented according to the methods of step 601 and step 602 of the embodiment 1. The content of the method is incorporated herein, and details are not described herein.

In this embodiment, REs that are not utilized are reassigned to use by several CCEs such that these CCEs can exceed the size limit of a predetermined size (36 REs). Since these additional CCEs that obtain RE resources do not necessarily contain an integer number of REGs, the interleave based on the REG size (4 REs) is no longer applicable, so the inventive embodiment accordingly interleaves and maps with 2 REs as the smallest unit.

In order to make the methods of Embodiment 1 and Embodiment 2 more clear and understandable, the methods of Embodiment 1 and Embodiment 2 will be described in detail below by way of some specific examples. Figure 8 shows a simple and feasible RE assignment process diagram.

As shown in FIG. 8, the unused REs are divided into groups of k REs, and several packets can be obtained, and each packet (ie, k REs) is again allocated to one CCE, thereby increasing the size of the CCE. To 36+k REs, to indicate the difference, the control channel particles of the E-PDCCH are generally referred to as E-CCE. The RE redistribution process follows some basic principles, for example: the number of k should be even, thus ensuring smooth implementation of SFBC coding; for example: determining which CCEs an unused RE will be assigned according to certain rules; for example: For allocation A possible packet of less than k REs is finally assigned to a CCE. Both the base station and the user (UE) follow the above basic principles, so the user can restore the operation of the originating base station, thereby demodulating the control information sent to itself.

In this embodiment, as shown in FIG. 8, the allocation process generates an E-CCE containing 36+k REs due to

36+k is not necessarily a multiple of 4, and an E-CCE does not necessarily contain an integer number of REGs, so the REG-based interleaving in the legacy PDCCH is no longer applicable here. Embodiments of the present invention define new REG sizes to address this problem. The resource particle group in the E-PDCCH is called E-REG, and each E-REG is defined by 2 REs. Each E-CCE will contain an integer number of E-REGs, which can be based on the E-REG size (2). RE) Interleaving of E-CCE. The subsequent resource mapping is also performed in units of E-REG. Since each PRB pair can be divided into an integer number of E-REGs, mapping resources in units of E-REG is beneficial to the full utilization of resources, and also facilitates the implementation of SFBC/STBC. Figure 9 shows the interleaving process in E-REG.

In order to make the redistribution process of the unused RE in FIG. 8 and the interleaving process of the E-PDCCH in FIG. 9 clearer and easier to understand, the E-CCE division, interleaving, and mapping process will be described below by way of an embodiment. For example, an E-PDCCH resource configuration that has appeared before is taken as an example, as shown in FIG.

FIG. 10 is a schematic diagram showing the configuration of an E-PDCCH resource and a reference signal.

In FIG. 10, four PRB pairs uniformly distributed in the total system bandwidth are allocated to the E-PDCCH, and the reference signal configuration of each PRB pair is as shown in FIG. 10, and the number of REs available in each PRB pair is 106. The total number of available REs for the four PRB pairs is 424. Since one CCE contains 36 REs, 424 REs can accommodate 11 CCEs and the remaining 28 REs are unused. For the remaining 28 REs, according to the method of the present embodiment, according to the value of k=4, it can be divided into 7 groups (k can also have other values, here 4 is taken as an example). As to which CCEs the remaining 28 REs are assigned to, a predetermined policy can be set, as described above, according to a predetermined policy. In the example of Figure 8, the allocation is made to the even-numbered CCE and then to the odd-numbered CCE. The rules (that is, the predetermined strategy), this way is beneficial to ensure that the highly aggregated E-PDCCH still has similar dimensions. Of course, other rules can also be used to determine the location of the CCE that can allocate the RE, not enumerated.

FIG. 11 is a schematic diagram of allocating E-PDCCH resources shown in FIG. 10 according to a method according to an embodiment of the present invention.

As shown in Figure 11, six RE packets (each containing 4 REs) are added to 0, 2, 4, 6, and 8, respectively.

The numbered CCE, then the remaining one is added to the CCE numbered 1, which ultimately forms the E-CCE arrangement in Figure 9. In the example shown in Figure 11, the E-CCE has both 36 and 40 sizes. After that, all E-CCEs are interleaved with 2 REs as the minimum unit, and the interleaving process is still as shown in Fig. 9. After the interleaving, a new E-REG sequence is obtained, and the resource mapping is performed in units of E-REG. For example, the E-REG position can be divided for each PRB pair according to the manner of FIG.

As shown in Figure 12, the number of REs available for E-PDCCH in a PRB pair is always an even number. Therefore, resource mapping with 2 RE units can always guarantee that a PRB pair contains an integer number of E-REGs. In addition, the use of 2 REs as resource mapping units facilitates SFBC/STBC implementation. For example, in Figure 12, the OFDM symbols appearing for DM-RS and CSI-RS can be STBC mapped, which can avoid the situation where multiple REs are separated between the same SFBC codes in Figure 5 (1). The E-REG sequence output after the final interleaving will be mapped to all four P B pairs, and each PRB pair will be mapped according to the position shown in Figure 12.

For the 28 REs remaining in Figure 10, the RE assignment given in Figure 11 takes the value k = 4, and Figure 13 shows the RE assignment process for k = 2.

The allocation of Figure 11 actually focuses on increasing the size of certain E-CCEs to improve the transmission performance of these E-CCEs, while Figure 13 focuses on allocating E-CCEs as much as possible, with a final E-CCE of only 40 and 38 sizes can be seen as 36+kn 36+k ₂ , where k ₁₌ 4, k ₂ =2, which is equivalent to the extension of the 36+k case in Figure 8. The subsequent E-REG interleaving and mapping are also performed in accordance with the manner of FIG. 9 and FIG. 12, and will not be repeated.

The method of FIG. 13 can also be regarded as dividing an unused RE into a plurality of groups having two sizes, one size being 4 REs per group, that is, 1^=4, a total of 3 groups, and another size. For each group contains 2 REs, ie k ₂ = 2, a total of 8 groups. Then assign the group containing 4 REs to the even-numbered CCEs, such as CCEs numbered 0, 2, 4, and assign the group containing 2 REs to the odd-numbered CCEs and other even-numbered CCEs. For example, CCEs numbered 1, 3, 5, 7, 9, 6, 8, 10. The foregoing allocation rules are merely illustrative, and the embodiment is not limited thereto. The present invention further provides a base station, as described in Embodiment 3 below, the principle of solving the problem by the base station is similar to the resource allocation method and the distributed transmission method of the E-PDCCH of Embodiment 1 or Embodiment 2, For specific implementations, reference may be made to the implementation of the methods of Embodiment 1 and Embodiment 2, and the details are not described again.

Example 3

The embodiment of the invention further provides a base station. 14 is a schematic diagram of the composition of the base station. Referring to FIG. 14, the base station includes:

a dividing unit 141, which divides the RE allocated to the E-PDCCH into a plurality of CCEs according to a predetermined size of the CCE;

The allocating unit 142 allocates the remaining REs of less than one CCE to the CCE according to a predetermined policy.

In one embodiment, the allocating unit 142 includes:

a first dividing module 1421, which divides the remaining REs of less than one CCE into multiple groups, each group including a predetermined number of REs;

a first allocating module 1422, which allocates the REs of each group to at least one of the CCEs according to a predetermined policy;

Wherein the predetermined number is an even number.

In this embodiment, the first allocating module 1422 allocates the RE that cannot be grouped to a CCE when there are REs that are not grouped in the remaining REs.

In another embodiment, the allocating unit 142 includes:

a second dividing module 1423, which divides the remaining REs of less than one CCE into multiple groups having multiple sizes;

The second allocating module 1424 assigns each group of REs to one of the CCEs according to a predetermined policy; wherein the number of REs of each size is an even number.

In an embodiment, the base station may further include:

The transmitting unit 143 performs interleaving and resource mapping on the CCEs that allocate the remaining REs of less than one CCE in units of pre-defined RE groups;

The pre-defined RE group includes 2 REs for each RE group.

With the base station of this embodiment, the unused REs are reassigned to a number of CCEs, so that the CCEs can exceed the size limit of 36 REs, thereby overcoming the resources according to the conventional PDCCH. The division method, when dividing the RE resources allocated to the E-PDCCH, the technical problem of insufficient utilization of the generated resources.

Example 4

The embodiment of the invention further provides a distributed transmission method of an E-PDCCH. Figure 15 is a flow chart of the method. Referring to Figure 15, the method includes:

Step 1501: Perform resource division on the RE allocated to the E-PDCCH.

Step 1502: Perform interleaving and resource mapping on the RE allocated to the E-PDCCH in units of pre-defined RE groups.

The pre-defined RE group includes 2 REs for each RE group.

In step 1501, the REs allocated to the E-PDCCH are not limited. For example, the REs allocated to the E-PDCCH may be divided according to the resource partitioning methods of Embodiment 1 and Embodiment 2; In some methods, each PRB pair allocated to the E-PDCCH is first divided into several equal parts, each of which is used as an E-CCE, so that the E-CCE will no longer be limited by the size of 36 REs, so there will be no The RE resource being used.

In step 1502, the REs allocated to the E-PDCCH are interleaved and resource mapped in units of 2 REs.

With the method of the present embodiment, since the granularity of units for performing interleaving and resource mapping is reduced, resource utilization is thereby improved.

The present invention further provides a base station, as described in the following embodiment 5. The principle of the problem solved by the base station is similar to the distributed transmission method of the E-PDCCH of the fourth embodiment. The implementation of the method, the same points will not be repeated.

Example 5

The embodiment of the invention further provides a base station. 16 is a schematic diagram of the composition of the base station. Referring to FIG. 16, the base station includes:

a dividing unit 161, which performs resource division on the RE allocated to the E-PDCCH;

a transmitting unit 162, which performs interlacing and resource mapping on REs allocated to the E-PDCCH in units of pre-defined RE groups;

The pre-defined RE group includes 2 REs for each RE group.

With the base station of this embodiment, since the granularity of units for performing interleaving and resource mapping is reduced, thereby improving Resource utilization.

Example 6

The embodiment of the invention further provides a resource allocation method for an E-PDCCH. Figure 17 is a flow chart of the method. Referring to Figure 17, the method includes:

Step 1701: divide the RE included in each PRB pair allocated for the E-PDCCH into multiple E-CCEs according to a predetermined policy by using two adjacent REs as a minimum unit.

In an embodiment, the predetermined policy may be: first dividing the REs in the frequency domain, and dividing the REs in the frequency domain does not ensure that the two REs are adjacent, and dividing the REs in the time domain.

In one embodiment, each of the PRBs allocated for the E-PDCCH may be divided into four E-CCEs.

According to the method of the embodiment of the present invention, each PRB pair allocated to the E-PDCCH is divided into several CCEs, and two adjacent REs are used as a minimum unit in the division, and each CCE is ensured to have a similar RE size. The method does not generate an unused RE, and solves the performance inequality caused by the large difference in the size of the divided E-CCEs in the existing partitioning method.

Example 7

The embodiment of the invention further provides a distributed transmission method of an E-PDCCH. Figure 18 is a flow chart of the method. Referring to Figure 18, the method includes:

Step 1801: divide the RE included in each PRB allocated to the E-PDCCH into multiple E-CCEs according to a predetermined policy by using two adjacent REs as a minimum unit;

Step 1802: Perform interleaving and resource mapping on the REs included in each PRB pair allocated to the E-PDCCH in units of pre-defined RE groups or in units of the E-CCE.

The pre-defined RE group includes 2 REs for each RE group.

In this embodiment, the step 1801 can be implemented by the step 1701 of the embodiment 6, and the content thereof is incorporated herein, and details are not described herein again.

The method in this embodiment is applicable to the transmission of the user search space of the E-PDCCH, and is also applicable to the transmission of the common search space of the E-PDCCH. The method of the embodiment of the present invention is applicable to control information transmission using SFBC.

With the method of the embodiment, in terms of resource division, the size of each E-CCE is substantially the same, and the performance inequality is overcome; in the aspect of interleaving and mapping, interleaving and mapping are performed in units of E-CCE, or The two REs are interleaved and mapped, ensuring that the two REs used as SFBC are always adjacent to each other, improving the transmission performance of the SFBC.

In order to make the methods of Embodiment 6 and Embodiment 7 more clear and understandable, the methods of Embodiment 6 and Embodiment 7 will be described in detail below by way of some specific examples.

In order to solve the problem of insufficient resource utilization, the prior art provides a method of dividing each P B pair into several equal parts, each serving as an E-CCE. In this way, the E-CCE will no longer be limited by the size of 36 REs, so there will be no unused RE resources. For example, divide a PRB pair into 4 E-CCEs. Figure 19 shows a conventional frequency division method.

As shown in Figure 19, it is still assumed that four PRB pair resources are allocated for the E-PDCCH. By dividing a PRB pair into three groups of REs in the frequency domain, four E-CCEs are obtained, and the E-CCEs are 19, 25, 23, and 21 REs, respectively. One problem with this division is that the size of the E-CCE is not uniform enough. For example, the largest E-CCE in Figure 18 is even 6 REs more than the smallest E-CCE, which will cause performance inequality. Another problem is the SFBC mapping, that is, within an E-CCE, it is not guaranteed that the two REs used as the SFBC are always adjacent to each other, and the non-adjacent REs used as the SFBC will cause performance loss. In addition, since the number of REs contained in the E-CCE is singular, the next isolated RE will remain in the SFBC pairing, and the individual REs cannot perform SFBC transmission.

In order to solve the above problem, the embodiment of the present invention may perform resource division according to the method of Embodiment 6 or Embodiment 7. FIG. 20 is a schematic diagram of E-CCE division (multiplexing) according to the method of the embodiment of the present invention.

Figure 20 shows two examples of E-CCE partitioning. All REs marked with "0" constitute E-CCE _Q , and so on. The division is performed with 2 adjacent REs (E-REG) as the smallest unit to facilitate SFBC/STBC mapping. In the OFDM symbols in which DM-RS and CSI-RS appear, there may be STBC mode mapping, and others are mapped in SFBC mode. Each of the four E-REGs constitutes a numbered cycle, thereby ensuring that the PRB is equally divided as much as possible. According to this division, in the end, the difference between the different E-CCEs is at most 2 REs, so that the maximum division can be achieved. Moreover, the two REs used as SFBC and STBC are always in adjacent positions, thereby ensuring the space/time coding performance. FIG. 20 multiplexes four E-CCEs as an example. For other numbers of E-CCE multiplexes, they can be divided in a similar manner, and are not enumerated. The foregoing E-CCE multiplexing scheme actually determines the number of REs included in each E-CCE, and globally numbers all E-CCEs in the four PRB pairs allocated to the E-PDCCH, and can also form the search space used previously. Concept, the search space is shown in Figure 21.

For the E-CCE sequence, since the resource mapping position of the E-CCE has been defined in the foregoing Fig. 20, interleaving and mapping in units of E-CCE can be performed. The E-CCE interleaving process is illustrated by FIG.

After the E-CCE interleaving, the new E-CCE sequence output is obtained, and then the resource mapping can be performed according to the E-CCE resource location defined in FIG. 20, and the new E-CCE sequence is mapped to the four PRB pairs of the E-PDCCH. transmission.

In this embodiment, for the search space shown in FIG. 21, the definition of the previous E-REG can still be used, and the E-REG is used as the minimum unit for interleaving, that is, the interleave of 2 RE units, and then according to the rule of FIG. Perform resource mapping in units of E-REG. Since the interleaving and resource mapping are performed based on E-REG, the E-CCE partitioning shown in Fig. 20 actually only serves to evenly divide the size of each E-CCE.

Figure 20 divides to get the exact same E-CCE size. Another embodiment is given below, in which the multiplexed E-CCEs are different in size, but the above procedure is equally applicable. For the reference signal configuration of two CRS ports, two DM-RS ports, and two CSI-RS ports, Figure 23 shows the multiplexing of two E-CCEs in one PRB pair.

Based on the E-CCE partitioning of Fig. 23, the corresponding search space is as shown in Fig. 24. Figure 24 shows an example of an E-CCE with 28 REs in every 4 E-CCEs. E-CCE arrangements can also have other options, as long as the base station and the user agree on this.

Next, interleaving based on E-REG (2 REs) is performed, as shown in Figure 9. For interwoven

The E-REG sequence is further mapped in units of E-REG. The location of the E-REG in the PRB pair is shown in Figure 12. All E-REGs are mapped to the four PRB pairs in which the E-PDCCH is located. Interleaving and resource mapping can also be performed in units of E-CCE, and will not be described again.

For a scheme of multiplexing multiple E-CCEs in a PRB pair, the user performs demapping and deinterleaving operations, and the user can know the corresponding search space location by knowing the number of E-CCEs multiplexed within one PRB pair, and then Perform blind detection and demodulation of the E-PDCCH. The base station can semi-statically configure the number of E-CCEs multiplexed within one PRB.

The present invention further provides a base station, as described in the following Embodiment 8, the principle of solving the problem by the base station is similar to the resource allocation method and the distributed transmission method of the E-PDCCH of Embodiment 6 or Embodiment 7, For specific implementations, reference may be made to the implementation of the methods of Embodiment 6 and Embodiment 7, and the same portions are not described again.

Example 8

The embodiment of the invention further provides a base station. 25 is a schematic structural diagram of the base station. Referring to FIG. 25, the base station includes:

The dividing unit 251 divides the RE included in each PRB pair allocated to the E-PDCCH into a plurality of E-CCEs according to a predetermined policy by using two adjacent REs as a minimum unit.

In an embodiment, the base station further includes:

The transmitting unit 252 is configured to perform interleaving and resource mapping on the RE included in each PRB pair allocated to the E-PDCCH in units of a predefined RE group or in units of the E-CCE;

The pre-defined RE group includes 2 REs for each RE group.

In this embodiment, the predetermined policy is: first, the REs in the frequency domain are divided, and when the REs in the frequency domain are not divided to ensure that the two REs are adjacent, the REs in the time domain are divided.

With the base station of this embodiment, in terms of resource division, the size of each E-CCE is substantially the same, which overcomes performance inequality; in terms of interleaving and mapping, interleaving and mapping are performed in units of E-CCE, or The two REs are interleaved and mapped, ensuring that the two REs used as SFBC are always adjacent to each other, improving the transmission performance of the SFBC.

The embodiment of the present invention further provides a computer readable program, wherein when the program is executed in a base station, the program causes the computer to execute the resource of the E-PDCCH described in Embodiment 1 or Embodiment 6 in the base station. Or the allocation method; or the program causes the computer to perform the distributed transmission method of the E-PDCCH described in Embodiment 2, Embodiment 4 or Embodiment 7 in the base station.

The embodiment of the present invention further provides a storage medium storing a computer readable program, wherein the computer readable program causes a computer to perform the resource allocation method of the E-PDCCH described in Embodiment 1 or Embodiment 6 in a base station, Or the distributed transmission method of the E-PDCCH according to Embodiment 2, Embodiment 4 or Embodiment 7.

The above apparatus and method of the present invention may be implemented by hardware, or may be implemented by hardware in combination with software. The present invention relates to a computer readable program that, when executed by a logic component, enables the logic component to implement the apparatus or components described above, or to cause the logic component to implement the various methods described above Or steps. Logic components such as field programmable logic components, microprocessors, processors used in computers, and the like. The present invention also relates to a storage medium for storing the above program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory, or the like.

The present invention has been described above in connection with specific embodiments, but it should be clear to those skilled in the art that The description is illustrative and not intended to limit the scope of the invention. A person skilled in the art can make various modifications and changes to the present invention within the scope of the present invention.

Claims

Claim

A resource allocation method for an enhanced physical downlink control channel, where the method comprises: resource particles allocated to an enhanced physical downlink control channel (E-PDCCH) according to a predetermined size of a control channel particle (CCE) (RE) is divided into multiple CCEs;

2. The method according to claim 1, wherein the remaining REs of less than one CCE are allocated to the CCE according to a predetermined policy, including:

The remaining REs of less than one CCE are divided into groups, each group including a predetermined number of REs; and the REs of each group are allocated to at least one of the CCEs according to a predetermined policy.

3. The method according to claim 2, wherein

If there are REs that are not grouped in the remaining REs, the REs that are not grouped are allocated to one CCE.

4. The method of claim 2, wherein the predetermined number is an even number.

5. The method according to claim 2, wherein the predetermined policy is:

According to the cyclic shift method, first assign to the even-numbered CCE, and then assign to the odd-numbered CCE; or,

According to the cyclic shift method, the odd-numbered CCEs are first allocated, and then assigned to the even-numbered CCEs; or

Assign to the CCE of the specified number.

6. The method according to claim 1, wherein the remaining REs of less than one CCE are allocated to the CCE according to a predetermined policy, including:

Dividing the remaining RE of less than one CCE into multiple groups having multiple sizes;

Assigning each group of REs to one of the CCEs according to a predetermined policy;

Among them, the number of REs of each size is even.

A method for distributed transmission of an E-PDCCH, where the method includes:

CCEs that allocate REs of the remaining less than one CCE in units of pre-defined RE groups Interleave and resource mapping.

8. The method according to claim 7, wherein the pre-defined RE group contains 2 REs for each RE group.

9. The method according to claim 7, wherein the remaining REs of less than one CCE are allocated to the CCE according to a predetermined policy, including:

Dividing the remaining REs of less than one CCE into a plurality of groups, each group including a predetermined number of REs;

The REs of each group are assigned to at least one of the CCEs according to a predetermined policy.

10. The method according to claim 9, wherein

If there are REs that are not grouped in the remaining REs of less than one CCE, the REs that are not grouped are allocated to one CCE.

11. The method of claim 9, wherein the predetermined number is an even number.

12. The method according to claim 9, wherein the predetermined policy is:

Assign to the CCE of the specified number.

The method according to claim 7, wherein the remaining REs of less than one CCE are allocated to the CCE according to a predetermined policy, including:

Among them, the number of REs of each size is even.

A base station, where the base station includes:

a dividing unit that divides the RE allocated to the E-PDCCH into a plurality of CCEs according to a predetermined size of the CCE; and an allocating unit that allocates the remaining REs of less than one CCE to the CCE according to a predetermined policy.

The base station according to claim 14, wherein the allocating unit comprises:

a first dividing module, which divides the remaining REs of less than one CCE into multiple groups, each group including a predetermined number of REs;

a first allocation module, which assigns each group of REs to at least one of the CCEs according to a predetermined policy on;

Wherein the predetermined number is an even number.

16. The base station according to claim 15, wherein

The first allocation module allocates the RE that cannot be grouped to a CCE when there are REs that are not grouped in the remaining REs.

The base station according to claim 14, wherein the allocating unit comprises:

a second partitioning module, which divides the remaining REs of less than one CCE into multiple groups having multiple sizes; and a second allocation module that allocates each group of REs to one of the CCEs according to a predetermined policy; Among them, the number of REs of each size is even.

The base station according to claim 14, wherein the base station further comprises:

a transmission unit, which performs interleaving and resource mapping on a CCE that allocates the remaining REs of less than one CCE in units of a predefined RE group;

The pre-defined RE group includes 2 REs for each RE group.

A method for distributed transmission of an E-PDCCH, where the method includes:

Allocating the RE allocated to the E-PDCCH for resource division;

20. A base station, where the base station includes:

a dividing unit that allocates resources to the RE of the E-PDCCH for resource division;

The pre-defined RE group includes 2 REs for each RE group.

A resource allocation method for an E-PDCCH, where the method includes:

The method according to claim 21, wherein the predetermined policy is: first, the REs in the frequency domain are divided, and when the REs in the frequency domain are divided, the two REs are not adjacent, and the time domain is The RE on the division is divided.

A method for distributed transmission of an E-PDCCH, where the method includes: Dividing the REs included in each PRB allocated to the E-PDCCH into a plurality of E-CCEs according to a predetermined policy by using two neighboring REs as a minimum unit;

The pre-defined RE group includes 2 REs for each RE group.

The method according to claim 23, wherein the predetermined policy is: first, the REs in the frequency domain are divided, and when the REs in the frequency domain are divided, the two REs are not adjacent, and the time domain is The RE on the division is divided.

25. A base station, where the base station includes:

The dividing unit divides the RE included in each PRB pair allocated to the E-PDCCH into a plurality of E-CCEs according to a predetermined policy by using two adjacent REs as a minimum unit.

The base station according to claim 25, wherein the base station further comprises:

a transmission unit, which performs interleaving and resource mapping on a RE included in each PRB pair allocated to the E-PDCCH in units of a predefined RE group, or in units of the E-CCE;

The pre-defined RE group includes 2 REs for each RE group.

The base station according to claim 25, wherein the predetermined policy is: first, the REs in the frequency domain are divided, and when the REs in the frequency domain are divided, the two REs are not adjacent, and the time domain is The RE on the division is divided.

28. A computer readable program, wherein the program causes a computer to perform a resource of the E-PDCCH according to any one of claims 1-6, 21-22 in the base station when the program is executed in a base station Alternatively, the program causes the computer to perform the distributed transmission method of the E-PDCCH according to any one of claims 7-13, 19, 23-24 in the base station.

A storage medium storing a computer readable program, wherein the computer readable program causes a computer to perform a resource allocation method of the E-PDCCH according to any one of claims 1-6, 21-22 in a base station, Or the distributed transmission method of the E-PDCCH according to any one of claims 7-13, 19, and 23-24.