Detailed Description
In order to improve the protocol flow, the embodiment of the invention provides a method for indicating and confirming time-frequency resources in CoMP transmission.
Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
In an embodiment of the present invention, a transmission point is defined as a group of transmission antennas with the same geographical location, and different sectors of the same site correspond to different transmission points. In CoMP transmission, transmission points directly and/or indirectly participating in data transmission to a UE form a coordinated transmission set, wherein the transmission points transmitting PBCH (physical broadcast channel) signaling to the UE are referred to as serving points, and others may be referred to as non-serving points. Meanwhile, in order to implement CoMP transmission, the UE is also required to feed back channel state information of corresponding transmission points to the network side, and a set of the transmission points fed back with the channel state information by the UE is also called a feedback set.
In the embodiment of the present invention, when the network side indicates time-frequency resources to the UE, the DCI may be used to indicate a resource allocation situation of a PDSCH (physical downlink shared channel) to the UE, or may indicate a resource allocation situation of an enhanced physical downlink control channel (enhanced physical downlink control channel) to the UE-PDCCH through a high layer signaling.
Referring to fig. 1, in the embodiment of the present invention, the base station includes a communication unit 10, a first processing unit 11, a second processing unit 12, and a third processing unit 13, wherein,
a first processing unit 11, configured to notify the UE of system bandwidths of at least two transmission points, and select, according to a preset manner, the system bandwidth of at least one transmission point from the system bandwidths of the at least two transmission points as a target bandwidth;
a second processing unit 12, configured to determine a time-frequency resource used when performing data transmission on the UE;
a third processing unit 13, configured to determine, based on the at least one target bandwidth, indication content and an indication manner of a time-frequency resource in the corresponding at least one DCI;
a communication unit 10, configured to send the at least one DCI to the UE, so that the UE determines the allocated time-frequency resource according to the at least one DCI.
Referring to fig. 2, in the embodiment of the present invention, the UE includes a communication unit 20, a first control unit 21, and a second control unit 22, wherein,
a first control unit 21, configured to obtain system bandwidths of at least two transmission points according to a notification from a base station, and select a system bandwidth of at least one transmission point from the system bandwidths of the at least two transmission points as a target bandwidth in a preset manner that is the same as that of the base station;
a communication unit 20, configured to receive at least one DCI transmitted by a base station for performing time-frequency resource indication;
and a second control unit 22, configured to determine, based on the at least one target bandwidth, a time-frequency resource allocated by the base station according to the received at least one DCI.
Based on the above technical solution, referring to fig. 3, in the embodiment of the present invention, a detailed flow of performing time-frequency resource indication to the UE by the base station is as follows:
step 300: the base station informs the UE of the system bandwidths of at least two transmission points, and selects the system bandwidth of at least one transmission point as a target bandwidth from the system bandwidths of the at least two transmission points according to a preset mode.
In this embodiment, the base station may represent any one or more transmission points in the cooperative transmission set, as long as the time-frequency resource indication can be performed to the UE. When notifying the system bandwidths of at least two transmission points to the UE, the base station notifies the system bandwidths of part or all transmission points in a coordinated transmission set corresponding to the UE; or notifying the system bandwidth of part or all transmission points in the feedback set corresponding to the UE; the base station may transmit the system bandwidths of the at least two transmission points to the UE by using a high-level signaling or DCI, and further, if the base station fails to determine whether the UE receives the system bandwidths of the at least two transmission points, in order to ensure normal operation of the system, the base station may directly determine the system bandwidth of the service point corresponding to the UE as a target bandwidth, and perform time-frequency resource indication to the UE based on the target bandwidth in a subsequent process.
On the other hand, if the UE has successfully received the system bandwidths of the at least two transmission points sent by the base station, the base station selects the system bandwidth of at least one transmission point as a target bandwidth from the system bandwidths of the at least two transmission points according to a preset manner, specifically: the base station may select a system bandwidth of a transmission point with the largest system bandwidth as a target bandwidth, may select a system bandwidth of a transmission point with the smallest system bandwidth as a target bandwidth, may select a system bandwidth of a service point as a target bandwidth, and may also select system bandwidths of all transmission points as target bandwidths (that is, there are multiple target bandwidths).
Step 310: and the base station determines time-frequency resources used by the UE for data transmission.
Specifically, the base station may determine, according to the channel state information reported by the UE, the service condition and the network load of the UE, a data transmission scheme used for the UE (i.e., which transmission points in the coordinated transmission set transmit data to the UE), and a time-frequency resource used in the data transmission scheme, which is also referred to as a PDSCH (physical downlink shared channel) resource.
Step 320: and the base station determines the indication content and the indication mode of the time-frequency resource in the corresponding at least one DCI based on the at least one target bandwidth.
In this embodiment, the indication content and the indication mode (e.g., bit length) of the time-frequency resource in CoMP transmission adopted in a certain DCI format do not affect the use of other DCI formats (e.g., bit lengths); for example, it is agreed that the DCIformat2C format is adopted to support CoMP transmission, and when the DCIformat2C format is adopted to indicate time frequency resources, the method is adopted to determine the target bandwidth and the indication content and indication mode of the corresponding time frequency resources, and the adopted bit length does not affect the bit length adopted in the DCIformat1A, DCIformat1B and other formats. Wherein, the bit length of other DCI formats may still be determined by the system bandwidth of the UE corresponding to the service point.
On the other hand, in this embodiment, if the base station selects only one target bandwidth, the base station may directly determine the indication content and the indication mode of the time-frequency resource in the corresponding DCI according to the target bandwidth; if the base station selects more than one target bandwidth, the base station may determine, according to each target bandwidth, the indication content and the indication mode of the time-frequency resource in the corresponding DCI, respectively, that is, one target bandwidth corresponds to one DCI, and at this time, the base station may send a plurality of DCIs to the UE.
When the base station determines the indication content and the indication mode of the time-frequency resource in the corresponding DCI according to any one target bandwidth, the base station may adopt, but is not limited to, the following three implementation modes:
the first mode is as follows: the base station determines each RBG divided in the system according to any one target bandwidth and the bit length used for bearing time-frequency resource allocation information in corresponding DCI, and indicates whether each RBG is allowed to be used by the UE or not to the UE through the bit of the corresponding length in the DCI based on the RBG contained in the time-frequency resource allocated to the UE.
For example, the base station indicates the allocation condition of the time-frequency resource by using the resource allocation type 0, which is specifically as follows:
the base station allocates the resource and indicates any one of the target bandwidths used in the resource allocation and the resource indicationDivision into NRBGRBGs, each RBG containing P Resource Blocks (RBs),wherein,represents the minimum integer not less than x, and the value of P is related to the target bandwidth, as shown in table 3:
TABLE 3
The base station adopts N in DCIRBGOne bit indicates whether each RBG is allocated to UE for use, NRBGOne bit and NRBGThe RBGs are in a one-to-one correspondence relationship, that is, the value of each bit indicates whether the corresponding RBG is allocated to the UE, for example, "1" indicates allocation, and "0" indicates no allocation.
The second way is: the base station determines each RBG and each RBG set divided in the system according to any one target bandwidth, and the bit length used for bearing time-frequency resource allocation information in corresponding DCI, and indicates whether each RBG set allows the UE to use or not and whether each RB in the RBG set allowed to use or not to allow the UE to use or not to use according to the RB corresponding to the RBG contained in the time-frequency resource allocated to the UE in the DCI through the bit with the corresponding length.
For example, the base station indicates the allocation condition of the time-frequency resource by using the resource allocation type 1, which is specifically as follows: the base station allocates the resource and indicates any one of the target bandwidths used in the resource allocation and the resource indicationDivision into NRBGRBGs, each RBG containing P RBs,will NRBGEach RBG is divided into P RBG sets, where the value of P is related to the target bandwidth, as shown in table 3.
Base station adoption in DCIOne bit indicates whether each RBG set is allowed to be used by the UE, andthe one bit indicates whether each RB in the RBG set allowed to be used by the UE is allowed to be used by the UE, whichBit and RBG set allowed to be used by UEThe RBs are in one-to-one correspondence, that is, the value of each bit indicates whether the corresponding RB is allocated to the UE, for example, "1" indicates allocation, and "0" tableNot shown as allocated.
The third mode is as follows: the base station indicates the mapping relation from VRB to PBR in DCI corresponding to any one target bandwidth, determines the bit length for bearing time-frequency resource allocation information in the DCI according to the any one target bandwidth, and indicates the starting resource number and VRB number of VRB to UE through the bit of corresponding length in the DCI based on the any one target bandwidth and the position of the time-frequency resource allocated to the UE.
For example, the base station indicates the allocation condition of the time-frequency resource by using the resource allocation type 2, which is specifically as follows:
the base station indicates the mapping relation of VRB to PRB through 1 bit in DCI and adopts the sameThe number of bits indicates the starting resource number and the number of VRBs allowed to be used by the UE, wherein,for any one of the target bandwidths, the bandwidth,
if DCIformat1A, DCIformat1B or DCIformat1D are used to support CoMP transmission, for DCIformat1A, DCIformat1B or DCIformat1D, the base station may be configured as described aboveIn one bit, the starting resource number RB of the VRB allowed for the UE is indicated by RIVstartAnd the number LCRBsWherein, the definition of RIV is:
if the number of the first and second antennas is greater than the predetermined number,then
If not, then, wherein L isCRBsNot less than 1 and not more than
If DCIformat1C is used to support CoMP transmission, for DCIformat1C, the BS can be configured as described aboveIn one bit, the starting resource number RB of the VRB allowed for the UE is indicated by RIVstartAnd the number LCRBsWherein RIV
Corresponding VRB starting resource number And the number of VRBs to which RIV corresponds Wherein,the value of which is related to the target bandwidth, as shown in table 4:
TABLE 4
In the following embodiments, the RIV is confirmed in the above manner, and will not be described again.
Step 330: and the base station sends the at least one DCI to the UE, and the UE determines the allocated time-frequency resource according to the received at least one DCI.
The method specifically comprises the following steps: the base station sends the generated one or more DCIs to the UE, and accordingly, the UE may determine the allocated time-frequency resources according to the received one or more DCIs, and the specific manner is introduced in the subsequent UE-side flow, which is not described herein again.
Based on the foregoing embodiments, referring to fig. 4, correspondingly, in the embodiments of the present invention, a detailed flow for the UE to perform time-frequency resource confirmation according to the indication of the base station is as follows:
step 400: and the UE acquires the system bandwidths of at least two transmission points according to the notification of the base station, and selects the system bandwidth of at least one transmission point as a target bandwidth from the system bandwidths of the at least two transmission points according to the same preset mode as the base station.
Specifically, the system bandwidths of the at least two transmission points, which are obtained by the UE according to the notification of the base station, may be the system bandwidths of some or all transmission points in the cooperative transmission set corresponding to the UE; or, the system bandwidth of some or all transmission points in the feedback set corresponding to the UE may also be used; the UE may obtain the system bandwidths of the at least two transmission points through a high layer signaling or a DCI notification sent by the base station; further, if the UE fails to receive the system bandwidths of the at least two transmission points notified by the base station, in order to ensure normal operation of the system, the UE may directly determine the system bandwidth of the service point corresponding to the UE as a target bandwidth, and determine the allocation condition of the time-frequency resource based on the target bandwidth in a subsequent process.
On the other hand, in this embodiment, after the UE successfully receives the system bandwidths of the at least two transmission points notified by the base station, the UE selects the system bandwidth of the at least one transmission point as a target bandwidth from the obtained system bandwidths of the at least two transmission points according to the same preset manner as the base station, specifically: the UE may select a system bandwidth of a transmission point with the largest system bandwidth as a target bandwidth, may select a system bandwidth of a transmission point with the smallest system bandwidth as the target bandwidth, may select a system bandwidth of a service point as the target bandwidth, and may also select system bandwidths of all transmission points as the target bandwidth (i.e., there are multiple target bandwidths).
In this embodiment, the indication content and the indication mode (e.g., bit length) of the time-frequency resource in CoMP transmission adopted in a certain DCI format do not affect the use of other DCI formats (e.g., bit lengths); for example, it is agreed that the DCIformat2C format is adopted to support CoMP transmission, and when the DCIformat2C format is adopted to indicate time frequency resources, the method is adopted to determine the target bandwidth and the indication content and indication mode of the corresponding time frequency resources, and the adopted bit length does not affect the bit length adopted in the DCIformat1A, DCIformat1B and other formats. Wherein, the bit length of other DCI formats may still be determined by the system bandwidth of the UE corresponding to the service point.
Step 410: and the UE receives at least one DCI which is sent by the base station and used for indicating time-frequency resources.
Step 420: and the UE determines the time-frequency resource allocated by the base station according to the received at least one DCI based on the at least one target bandwidth.
The method specifically comprises the following steps: if the UE only selects one target bandwidth, and correspondingly, the UE receives DCI sent by the base station, the UE directly determines the time-frequency resources allocated by the base station according to the received DCI based on the target bandwidth; if the UE selects a plurality of target bandwidths, and correspondingly, the UE will also receive a plurality of DCIs sent by the base station, the UE will determine, based on each target bandwidth, the time-frequency resources allocated by the base station according to the corresponding DCI, and combine the determination results, so that the time-frequency resource allocation situations indicated by the plurality of DCIs received by the UE may be different but are all the available time-frequency resources allocated to the UE by the base station, and therefore, the UE can combine (i.e., obtain a union) the time-frequency resources, thereby obtaining an available time-frequency resource set.
Corresponding to step 320, when the UE determines the time-frequency resource allocated by the base station according to the corresponding DCI based on any one of the target bandwidths, the following three implementation manners may be adopted, but are not limited to:
the first mode is as follows: and the UE determines each RBG divided in the system according to any one target bandwidth and the bit length used for bearing the time-frequency resource allocation information in the corresponding DCI, and determines whether each RBG is allowed to be used or not through the bits with the corresponding length.
For example: the UE determines the allocation of the time-frequency resource according to the resource allocation type 0, which specifically includes:
UE will choose any one target bandwidthDivision into NRBGRBGs, each RBG containing P RBs,wherein,represents the minimum integer not less than x, and the value of P is related to the target bandwidth, as shown in table 3.
UE in received corresponding DCIBy NRBGOne bit determines whether each RBG can be used, NRBGOne bit and NRBGThe RBGs are in a one-to-one correspondence relationship, that is, the value of each bit indicates whether the corresponding RBG is allocated to the UE, for example, "1" indicates allocation, and "0" indicates no allocation. On the other hand, NRBGThe reading position of the bit in the DCI may be indicated by the base station to the UE, or agreed by the base station and the UE, or executed according to a protocol, which is not described herein again.
The second way is: the UE determines each RBG and each RBG set divided in the system according to any one target bandwidth and the bit length used for carrying time-frequency resource allocation information in the corresponding DCI, and determines whether each RBG set is allowed to be used or not and whether each RB in the RGB set allowed to be used is allowed to be used or not through the bits with the corresponding length.
For example, the UE determines the allocation of the time-frequency resource according to the resource allocation type 1, which is specifically as follows:
UE will choose any one target bandwidthDivision into NRBGRBGs, each RBG containing P RBs,will NRBGEach RBG is divided into P RBG sets, where the value of P is related to the target bandwidth, as shown in table 3.
UE passing in corresponding DCIBit to determine whether each RBG set is allowed to be used, and throughOne bit determines whether each RB in the RBG set allowed to be used is allowed to be used, whichBit and RBG set allowed to be used by UEEach RB is in a one-to-one correspondence, that is, the value of each bit indicates whether the corresponding RB is allocated to the UE, for example, "1" indicates allocation, and "0" indicates no allocation. On the other hand, in the case of a liquid,a bit sumThe reading position of the bit in the DCI may be indicated by the base station to the UE, or agreed by the base station and the UE, or executed according to a protocol, which is not described herein again.
The third mode is as follows: and the UE determines the mapping relation from the VRB to the PBR according to the received DCI corresponding to any one target bandwidth, determines the bit length for bearing time-frequency resource allocation information in the DCI according to any one corresponding target bandwidth, and determines the starting resource number and the VRB number of the VRB through the bit of the corresponding length.
For example, the UE determines the allocation of the time-frequency resource according to the resource allocation type 2, which is specifically as follows:
the UE determines the mapping relation from the VRB to the PRB according to the 1-bit indication information carried by the DCI, and the mapping relation is passed through in the DCIThe number of bits determines the starting resource number and number of VRBs allowed to be used, wherein,for any one of the target bandwidths, the bandwidth,
if DCIformat1A, DCIformat1B, DCIformat1C, or DCIformat1D is used to support CoMP transmission, for DCIformat1A, DCIformat1B, DCIformat1D, or DCIformat1C, the UE may all be configured to support CoMP transmissionBy the aboveThe RIV carried by a bit determines the starting resource number RB of the VRB allowed for use by the UEstartAnd the number LCRBsWherein, the definition of RIV is the same as that of the base station side, and is not described herein again.
In summary, in the embodiments of the present invention, a base station notifies a UE of system bandwidths of at least two transmission points, selects a system bandwidth of at least one transmission point from the system bandwidths as a target bandwidth according to a preset manner, allocates a time-frequency resource to the UE according to the at least one target bandwidth, and performs time-frequency resource indication in at least one downlink signaling based on the at least one target bandwidth, and the UE selects the system bandwidth of at least one transmission point from the obtained system bandwidths of at least two transmission points as a target bandwidth according to the same preset manner according to the notification of the base station, and analyzes the received at least one downlink signaling based on the obtained at least one target bandwidth, thereby determining the time-frequency resource allocated by the base station. Therefore, in the CoMP transmission, under the condition that the system bandwidths of the transmission points in the cooperation set are possibly different, the unified indication of the time-frequency resources is realized, so that the UE can be ensured to perform effective data reception based on the obtained time-frequency resources, the system processing flow under the CoMP transmission is perfected, and the system performance is improved.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.