The disclosure is directed to a method for performing a hybrid automatic repeat request (HARQ) transmission and a user equipment.
The 3rd generation partnership project (3GPP) is an umbrella term for a number of standards organizations which develop protocols for mobile telecommunications. For example, 5G NR (new radio) is one protocol developed by 3GPP. Data packet is transmitted from transmitter to receiver. When the data packet arrives at receiver, receiver decodes the data packet and sends a corresponding feedback to the transmitter. If the receiver decodes the data packet correctly, the feedback can be a positive-acknowledgment (ACK). If the receiver decodes the data packet incorrectly, the feedback can be a negative-acknowledgment (NACK). The feedback is received by physical (PHY) layer first, and then it is passed to medium access control (MAC) layer. Network starts PHY layer retransmission if needed (e.g. if the feedback is a NACK). PHY layer provides one or more (re)transmissions to increase the chances of correct decoding. Therefore, hybrid automatic repeat request (HARQ) process operates at different layers. Specifically, the transmitter transmits a data packet, it temporarily stops and waits for the feedback from the receiver. After receiving the ACK, the transmitter stops the data packet. After receiving the NACK, the transmitter retransmits the data packet again via PHY layer.
In 5G NR, 3GPP specification has defined a codebook for carrying the feedback corresponding to the HARQ process. The codebook is comprised of a sequence of bits, which is constructed by feedback corresponding to multiple occasions for physical downlink shared channel (PDSCH) receptions. 3GPP has defined two type of codebook is defined, including Type-1 codebook and Type-2 codebook. The payload size of Type-2 codebook is dynamic, and the payload size of Type-1 codebook is preconfigured/predetermined. For reducing the probability of incorrectly decoding, slot aggregation is applied for scheduling the same data packet across multiple slots. Therefore, further improvements/enhancements can be considered for improving the resource utilization.
The disclosure provides a method for performing HARQ transmission and a user equipment.
A method for performing a hybrid automatic repeat request (HARQ) transmission at a user equipment (UE) according to the disclosure comprises: receiving a first configuration related to slot aggregation for physical downlink shared channel (PDSCH) reception; receiving a downlink control information (DCI); receiving a PDSCH indicted by the DCI across a first number of aggregated slots; and transmitting a codebook comprising a first information and a second information.
In an embodiment of the disclosure, the PDSCH comprises at least one transport block (TB), and the transport block comprises a plurality of code blocks (CBs).
In an embodiment of the disclosure, the first configuration is indicated via higher layer signaling.
In an embodiment of the disclosure, the higher layer signaling comprises at least one of the following signaling: a radio resource control (RRC) signaling, a medium access control (MAC) signaling, or a radio link control (RLC) signaling.
In an embodiment of the disclosure, the first number of aggregated slots is determined according to the first configuration.
In an embodiment of the disclosure, if the DCI indicates that the PDSCH comprises a retransmitted transport block, the first number of aggregated slots is determined according to the first configuration or the DCI.
In an embodiment of the disclosure, wherein if the DCI indicates that the PDSCH comprises a newly transmitted transport block, the first number of aggregated slots is determined according to the first configuration.
In an embodiment of the disclosure, if the UE is configured with transport block based (TB-based) transmission, a size of the codebook is related to a first value wherein the first value is related to the number of occasions for candidate PDSCH receptions.
In an embodiment of the disclosure, if the UE is configured with code block groups based (CBG-based) transmission, a size of the codebook is related to a first value and a second value wherein the first value is related to the number of occasions for candidate PDSCH receptions and the second value is related to one of followings: a maximum number of code block groups per transport block, a fixed value, a pre-determined value, a preconfigured value, or a configurable value.
In an embodiment of the disclosure, the first information comprises a positive acknowledgement (ACK) or a negative acknowledgement (NACK) associated with a HARQ process for the PDSCH.
In an embodiment of the disclosure, a number of available bits for carrying the second information is determined according to at least a size of the codebook and a size of the first information.
In an embodiment of the disclosure, the second information carried in the codebook is determined with a priority order.
In an embodiment of the disclosure, the priority order is predetermined or default.
In an embodiment of the disclosure, the priority order is determined according to at least one of following parameters: symbol number, slot number, subframe number, frame number, serving cell identifier, or bandwidth part identifier.
In an embodiment of the disclosure, the second information carried in the codebook is determined according to at least one of the following parameters: the number of available bits in the codebook, or the priority order.
In an embodiment of the disclosure, the second information comprises at least one of the following parameters: information related to battery life, information related to signal to noise plus interference ratio (SINR), information related to modulation and coding scheme (MCS), information related to channel quality indication (CQI), information related to quasi co-location (QCL) assumption, or information related to transmission power.
In an embodiment of the disclosure, the information related to SINR is determined according to at least one of following radio resources: the PDSCH reception, a reference signal of a serving cell, or a reference signal of neighbor cell.
In an embodiment of the disclosure, the information related to CQI is determined according to at least one of following radio resources: the PDSCH reception, a reference signal of a serving cell, or a reference signal of neighbor cell.
In an embodiment of the disclosure, the information related to QCL assumption is determined according to at least one of following radio resources: the PDSCH reception, a reference signal of a serving cell, or a reference signal of neighbor cell.
In an embodiment of the disclosure, the information related to transmission power is determined according to at least one of following radio resources: the PDSCH reception, a reference signal of a serving cell, or a reference signal of neighbor cell.
In an embodiment of the disclosure, in response to the first information comprises a NACK, the second information comprises a second number of aggregated slots.
In an embodiment of the disclosure, the method further comprises: receiving a second configuration related to code block groups of the PDSCH reception, wherein the code block groups are grouped from a plurality of code blocks comprised in a transport block of the PDSCH.
In an embodiment of the disclosure, the second configuration is indicated via higher layer signaling.
In an embodiment of the disclosure, in response to the first information comprises a NACK, the second information comprises HARQ-ACK feedback for the code block groups of the PDSCH.
In an embodiment of the disclosure, in response to the first information comprises a NACK, the second information comprises HARQ-ACK feedback for at least one group of code blocks of the PDSCH.
In an embodiment of the disclosure, the method further comprises: obtaining the maximum number of the code block groups of the transport block according to the second configuration.
In an embodiment of the disclosure, the method further comprises: grouping the code blocks according to the maximum number of code block groups and the number of available bits for carrying the second information.
In an embodiment of the disclosure, the grouping method of the code blocks comprises: calculating M=min(N, C), wherein N is the maximum number of code block groups per transport block, and C is the number of available bits for carrying the second information; the grouping method of the code blocks is obtained based on following: calculating M1=mod(C1, M),
wherein C1 is a number of code blocks per transport block; setting index m as 0 to M1−1; for groups with the indices m as 0 to M1−1, setting a group with index m to include K1 code block with indices m·K1+k, wherein k=0, 1, . . . , K1−1; for groups with indices m as M1 to M−1, setting the group with index m to include K2 code block with indices M1·K1+(m−M1)·K2+k, wherein k=0, 1, . . . , K2−1.
A user equipment according to the disclosure comprises: a storage, configured to store a program; and a processor, coupled to the storage, and configured to execute the program to: receive a first configuration related to slot aggregation for PDSCH reception; receive a DCI; receive a PDSCH indicted by the DCI across a first number of aggregated slots; and transmit a codebook comprising a first information and a second information.
To make the aforementioned more comprehensible, several embodiments accompanied with drawings are described in detail as follows.
The accompanying drawings are illustrated to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.
The UE 100 comprises a processor 110, a storage 120 and a communication component 130. The processor 110 is coupled to the storage 120 and the communication component 130. The processor 110 is, for example, a central processing unit (CPU), a physics processing unit (PPU), a programmable microprocessor, an embedded control chip, a digital signal processor (DSP), an application specific integrated circuit (ASIC), or other similar devices.
The storage 120 is, for example, any type of fixed or removable random-access memory (RAM), read-only memory (ROM), flash memory, hard disk drive, other similar apparatuses, or a combination of the apparatuses. The storage 120 stores a plurality of code fragments, and the code fragments are executed by the processor 110 after being installed, so as to execute the method for performing a hybrid automatic repeat request (HARQ) transmission.
The communication component 130 may be a chip or circuit using a local area network (LAN) technology, a wireless LAN (WLAN) technology, or a mobile communication technology. The local area network is, for example, Ethernet. The wireless local area network is, for example, Wi-Fi. The mobile communication technology is, for example, Global System for Mobile Communications (GSM), the third generation mobile communication technology (3G), the fourth generation mobile communication technology (4G), the fifth generation mobile communication technology (5G), and so on.
The UE 100 performs uplink and downlink communications with a base station (BS) through the communication component 130. For example, the BS could be synonymous with a variation or a sub-variation of a generation node B (gNB), an evolved node B (eNB), a Node-B, an advanced BS (ABS), a transmission reception point (TRP), an unlicensed TRP, a base transceiver system (BTS), an access point, a home BS, a relay station, a scatterer, a repeater, an intermediate node, an intermediary, satellite-based communication BSs, and so forth.
Please refer to
Next, in step S210, the processor 110 receives a downlink control information (DCI). For example, the DCI is sent from the BS to the UE 100, and carried by the physical downlink control channel (PDCCH). The DCI is a set of information which schedules PDSCH or physical uplink shared channel (PUSCH). The DCI provides the UE 100 with the necessary information such as physical layer resource allocation, power control commands, HARQ information, etc.
In one embodiment, the DCI may provide a parameter k1 for PDSCH to HARQ feedback. In 5G NR, if the UE 100 is configured to monitor PDCCH for DCI format 1_0, the parameter k1 is provided by a set of slot timing values {1, 2, 3, 4, 5, 6, 7, 8}. If the UE 100 is configured to monitor PDCCH for DCI format 1_1, the parameter k1 is provided by dl-DataToUL-ACK. If the UE 100 is configured to monitor PDCCH for DCI format 1_2, the parameter k1 is provided by dl-DataToUL-ACK-ForDCIFormat1_2. If the UE 100 is configured to monitor PDCCH for DCI format 1_1 and DCI format 1_2, the parameter k1 is provided by the union of dl-DataToUL-ACK and dl-DataToUL-ACK-ForDCIFormat1_2.
In step S215, the processor 110 receives a PDSCH indicted by the DCI across a first number of aggregated slots. The first number of aggregated slots is determined according to the first configuration. In one embodiment, the first configuration comprises the parameter “pdsch-AggregationFactor” signaled via higher layer signaling. In one embodiment, the higher layer signaling is a RRC signaling. The first number of aggregated slots is determined by the parameter “pdsch-AggregationFactor”. In one embodiment, the first number of the aggregated slots can be 1 or 2 or 4 or 8 slots. When the UE 100 is configured with pdsch-AggregationFactor>1, the same symbol allocation is applied across the pdsch-AggregationFactor slots.
Specifically, if the DCI indicates that the PDSCH comprises a newly transmitted transport block, the first number of aggregated slots is determined according to the first configuration (e.g. parameter “pdsch-AggregationFactor”). That is, the first number of aggregated slots determined by the first configuration is used for the initial transmission. In one embodiment, if the DCI indicates that the PDSCH comprises a retransmitted transport block, a second number of aggregated slots is determined according to the first configuration (e.g. parameter “pdsch-AggregationFactor”). That is, the second number of aggregated slots determined by the first configuration (e.g. parameter “pdsch-AggregationFactor”) is used for the retransmission.
In another embodiment, if the DCI indicates that the PDSCH comprises a retransmitted transport block, the second number of aggregated slots is determined according to the DCI. That is, the second number of aggregated slots determined by the DCI is used for the retransmission.
In another embodiment, the number of aggregated slots for initial transmission may be determined by the first configuration, and the number of aggregated slots for retransmission may be determined by the DCI.
In NR, for improving the transmission efficiency and radio resource utilization, the UE 100 may further receive a second configuration related to code block groups (CBGs) for the PDSCH reception. The CBGs are grouped from a plurality of code blocks (CBs) comprised in a transport block (TB) of the PDSCH. Specifically, the transport block is divided into multiple code blocks, and multiple CBs may be further grouped into one or more code block groups (CBGs).
For example, the second configuration related to CBGs comprises a parameter “maxCodeBlockGroupsPerTransportBlock” provided by a higher layer signaling (e.g. RRC signaling) and used for indicating the maximum number of CBGs per TB (e.g. NmaxCBG).
In step S220, the processor 110 transmits a codebook comprising a first information and a second information. In the embodiment, the codebook provides the feedback corresponding to the PDSCH to the BS. The UE 100 transmits the decoding result (e.g ACK or NACK) of the PDSCH to the BS. 3GPP includes two types of codebooks, i.e. Type-1 codebook and Type-2 codebook. Specifically, Type-1 codebook is a codebook with a size provided by higher layer signaling (i.e. the size of the Type-1 codebook is semi-static). Type-2 codebook is a codebook with a size provided by the DCI corresponding to the PDSCH reception (i.e. the size of the Type-2 codebook is dynamic).
In the embodiment, the Type-1 codebook is used for description. In an embodiment of the disclosure, if the UE is configured with TB-based transmission, the size of the codebook (i.e. Type-1 codebook) is related to a first value wherein the first value is related to the number of occasions for candidate PDSCH receptions.
In the embodiment, the Type-1 codebook is used for description. In an embodiment of the disclosure, if the UE is configured with CBG-based transmission, the size of the codebook (i.e. Type-1 codebook) is related to a first value and a second value. The first value is related to the number of occasions for candidate PDSCH receptions. The second value is related to one of followings: a maximum number of CGBs per TB, a fixed value, a pre-determined value, a preconfigured value, or a configurable value.
In one embodiment, the first information of the codebook comprises an ACK or a NACK associated with a HARQ process for the PDSCH. The second information of the codebook comprises at least one of the following parameters: information related to battery life, information related to signal to noise plus interference ratio (SINR), information related to modulation and coding scheme (MCS), information related to channel quality indication (CQI), information related to quasi co-location (QCL) assumption, or information related to transmission power. In one embodiment, the second information of the codebook comprises the information related to battery life. In one embodiment, the second information of the codebook comprises the information related to SINR. In one embodiment, the second information of the codebook comprises the information related to MCS. In one embodiment, the second information of the codebook comprises the information related to CQI. In one embodiment, the second information of the codebook comprises the information related to CQI. In one embodiment, the second information of the codebook comprises the information related to QCL assumption. In one embodiment, the second information of the codebook comprises the information related to transmission power. In another embodiment, the second information of the codebook comprises the information related battery life, SINR, and MCS. In one embodiment, the second information of the codebook comprises the information related to battery life, information related to signal to SINR, information related to MCS, information related to CQI, information related to QCL assumption, and information related to transmission power. In one embodiment, the second information of the codebook comprises the information related to battery life, information related to signal to SINR, information related to MCS, information related to CQI, information related to QCL assumption, or information related to transmission power.
The information related to SINR is determined according to at least one of following radio resources: the PDSCH reception, a reference signal of a serving cell, or a reference signal of neighbor cell. In one embodiment, the information related to SINR is determined according to the PDSCH reception. In another embodiment, the information related to SINR is determined according to the reference signal of a serving cell. In one embodiment, the information related to SINR is determined according to the reference signal of neighbor cell. In one embodiment, the information related to SINR is determined according to the PDSCH reception and the reference signal of neighbor cell. In one embodiment, the information related to SINR is determined according to the PDSCH reception, a reference signal of a serving cell, and a reference signal of neighbor cell. In one embodiment, the information related to SINR is determined according to the PDSCH reception, a reference signal of a serving cell, or a reference signal of neighbor cell.
The information related to CQI is determined according to at least one of following radio resources: the PDSCH reception, a reference signal of a serving cell, or a reference signal of neighbor cell. In one embodiment, the information related to CQI is determined according to the reference signal of the serving cell. In another embodiment, the information related to CQI is determined according to the PDSCH reception. In one embodiment, the information related to CQI is determined according to the reference signal of neighbor cell. In one embodiment, the information related to CQI is determined according to the PDSCH reception and a reference signal of neighbor cell. In one embodiment, the information related to CQI is the PDSCH reception, the reference signal of the serving cell, and the reference signal of the neighbor cell. In one embodiment, the information related to CQI is the PDSCH reception, the reference signal of the serving cell, or the reference signal of the neighbor cell.
The information related to QCL assumption is determined according to at least one of following radio resources: the PDSCH reception, a reference signal of a serving cell, or a reference signal of neighbor cell. In one embodiment, the information related to QCL assumption is determined according to the reference signal of neighbor cell. In one embodiment, the information related to QCL assumption is determined according to the reference signal of the serving cell. In another embodiment, the information related to QCL assumption is determined according to the PDSCH reception. In one embodiment, the information related to QCL assumption is determined according to the PDSCH reception and a reference signal of neighbor cell. In one embodiment, the information related to QCL assumption is determined according to the PDSCH reception, the reference signal of the serving cell, and a reference signal of neighbor cell. In one embodiment, the information related to QCL assumption is determined according to the PDSCH reception, the reference signal of the serving cell, or a reference signal of neighbor cell.
The information related to transmission power is determined according to at least one of following radio resources: the PDSCH reception, a reference signal of a serving cell, or a reference signal of neighbor cell. In one embodiment, the information related to transmission power is determined according to the PDSCH reception. In another embodiment, the information related to transmission power is determined according to the reference signal of the serving cell. In one embodiment, the information related to transmission power is determined according to the reference signal of the neighbor cell. In one embodiment, the information related to transmission power is determined according to the PDSCH reception, and the reference signal of the neighbor cell. In one embodiment, the information related to transmission power is determined according to the PDSCH reception, the reference signal of the serving cell, and the reference signal of the neighbor cell. In one embodiment, the information related to transmission power is determined according to the PDSCH reception, the reference signal of the serving cell, or the reference signal of the neighbor cell.
The above mentioned reference signal comprising SSB (synchronization signal block), CSI-RS (channel status information reference signal), SRS (sounding reference signal), etc.
The number of available bits for carrying the second information is determined according to a size of the codebook and a size of the first information. The second information carried in the codebook is determined with a priority order. Furthermore, the second information carried in the codebook is determined according to the number of available bits in the codebook and/or the priority order. In one embodiment, the priority order is predetermined or default. In another embodiment, the priority order is determined according to at least one of following parameters: symbol number, slot number, sub-frame number, frame number, serving cell identifier, or bandwidth part identifier. In one embodiment, the priority order is determined according to symbol number. In one embodiment, the priority order is determined according to slot number. In one embodiment, the priority order is determined according to sub-frame number. In one embodiment, the priority order is determined according to frame number. In one embodiment, the priority order is determined according to serving cell identifier. In one embodiment, the priority order is determined according to bandwidth part identifier. In one embodiment, the priority order is determined according to symbol number and slot number. In one embodiment, the priority order is determined according to symbol number, slot number, sub-frame number, frame number, serving cell identifier, and bandwidth part identifier. In one embodiment, the priority order is determined according to symbol number, slot number, sub-frame number, frame number, serving cell identifier, or bandwidth part identifier.
In
In the embodiment, the priority order is adapted to determine the second information in the codebook. Specifically, at least one parameter is carried in the second information which is determined by the priority order. For example, the priority order of the parameters used in the second information is shown in Table 1 if the PDSCH is correctly decoded.
In
In the embodiment, the priority order is adapted to determine the second information in the codebook. Specifically, at least one parameter is carried in the second information which is determined with the priority order. For example, the priority order of the parameters used in the second information is shown in Table 2 if the PDSCH is not correctly decoded.
In another embodiment, priority order can be set depending on at least one of the following parameters: a slot number, symbol number, sub-frame number, frame number, serving cell identifier, or bandwidth part identifier. For example, priority order can be set depending on the slot number. For example, priority order can be set depending on the symbol number. For example, priority order can be set depending on the sub-frame number. For example, priority order can be set depending on the frame number. For example, priority order can be set depending on the serving cell identifier. For example, priority order can be set depending on the bandwidth part identifier. For example, priority order can be set depending on the symbol number and the frame number. For example, priority order can be set depending on the slot number, the symbol number, the sub-frame number, the frame number, the serving cell identifier, and the bandwidth part identifier. For example, priority order can be set depending on the slot number, the symbol number, the sub-frame number, the frame number, the serving cell identifier, or the bandwidth part identifier. For example, Table 2 is used for the second information if the codebook is transmitted in a slot with an even number (e.g. #0, #2, #4, #6, #8). If the codebook is transmitted in a slot with an odd number (e.g. #1, #3, #5, #7, #9), Table 3 is used for the second information.
If the transport block is not decoded successfully, in step S905, the parameters used in the second information comprises at least one of the following parameters: the number of aggregated slots for its retransmission. Moreover, in step S907, the parameters used in the second information further comprises at least one of the parameters: information related to battery life, information related to SINR, information related to MCS, information related to CQI, information related to QCL assumption, or information related to transmission power. In response to the transport block decoding failure, the parameters and the priority order of the parameters used in the second information are is shown in Table 2 or Table 3. In terms of
If the transport block is not decoded successfully, in step S1005, the parameters used in the second information comprises HARQ-ACK feedback for at least one group of the CBs, and the number of aggregated slots for its retransmission. Moreover, the parameters used in the second information further comprises at least one of the parameters as shown in step S1007. Next, step S1007 is described using
In
In
For example, there are 4 CBGs, and 4 bits are configured for the storage space 1121. The first bit corresponds to CBG #0, the second bit corresponds to CBG #1, the third bit corresponds to CBG #3, and the fourth bit corresponds to CBG #3. It is assumed that CB #2 is not correctly decoded. That means that CBG #1 is not correctly decoded. Accordingly, {1, 0, 1, 1} is filled to the storage space 1121, wherein “1” corresponds to decoding success, and “0” corresponds to decoding failure.
For example, the DCI further provides binary representation for different number of aggregated slots. As shown in Table 5, the binary representation of 1 aggregated slot is “00”, the binary representation of 2 aggregated slots is “01”, the binary representation of 4 aggregated slots is “10”, and the binary representation of 8 aggregated slots is “11”. In the embodiment, it is assumed that the second number of aggregated slots is 4. Referring to Table 5, it can be known that and the binary representation is “10”, and “10” is filled to the storage space 1122.
In another embodiment, in response to the first information 1111 comprises the NACK, the number of aggregated slots for retransmission is filled in the codebook 1110 as the second information 1112. For example, referring to Table 5, it is assumed that the second number is 4, the binary representation “10” is filled into the storage space 1122.
In the embodiment of
Specifically, the UE 100 groups the CBs by the processor 110 according to the maximum number of CBGs and a number of available bits for carrying the second information 1112. For example, the processor 110 calculates M=min(N, C), wherein N is the maximum number of CBGs per transport block, and C is the number of available bits for carrying the second information 1112.
Next, the grouping of the CBs is obtained based on following. The processor 110 calculates M1=mod(C1, M),
wherein C1 is the number of CBs per transport block. And the processor 110 sets index m as 0 to M1−1. For groups with the indices m as 0 to M1−1, the processor 110 sets a group with index m to include K1 CB(s) with indices m·K1+k, wherein k=0, 1, . . . , K1−1. For groups with indices m as M1 to M−1, the processor 110 sets the group with index m to include K2 CB(s) with indices M1·K1+(m−M1)·K2+k, wherein k=0, 1, . . . , K2−1.
CASE A: it is assumed that N (the maximum number of CBGs per transport block) is 4, C (the number of available bits for carrying the second information) is 8, C1 (the number of CBs per transport block) is 22.
For groups with the indices m as 0 to M1−1 (e.g. group 0 to group 1), the group with index m includes K1 (which is 6) CBs with indices m·K1+k, wherein k=0, 1, . . . , K1−1 (which is 5). That is, the group 0 includes 6 CBs with indices 0, 1, 2, 3, 4, 5. The group 1 includes 6 CBs with indices 6, 7, 8, 9, 10, 11.
For groups with the indices m as M1 to M−1 (e.g. group 2 to group 3), the group with index m includes K2 (which is 5) CBs with indices M1·K1+(m−M1)·K2+k, wherein k=0, 1, . . . , K2−1 (which is 4). That is, the group 2 includes 5 CBs with indices 12, 13, 14, 15, 16. The group 3 includes 5 CBs with indices 17, 18, 19, 20, 21.
CASE B: it is assumed that N (the maximum number of CBGs per transport block) is 4, C (the number of available bits for carrying the second information) is 2, C1 (the number of CBs per transport block) is 22.
For groups with the indices m as 0 to M1−1, since M1=0, M1−1=−1, negative index is unreasonable. Accordingly, the case of “the groups with the indices m as 0 to M1−1” is not considered.
For groups with the indices m as M1 to M−1 (e.g. group 0 to group 1), the group with index m includes K2 (which is 11) CBs with indices M1·K1+(m−M1)·K2+k, wherein k=0, 1, . . . , K2−1 (which is 10). That is, the group 0 includes 11 CBs with indices 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. The group 1 includes 11 CBs with indices 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21.
CASE C: it is assumed that N (the maximum number of CBGs per transport block) is 4, C (the number of available bits for carrying the second information) is 4, C1 (the number of CBs per transport block) is 20.
For groups with the indices m as 0 to M1−1, since M1=0, M1−1=−1, negative index is unreasonable. Accordingly, the case of “the groups with the indices m as 0 to M1−1” is not considered.
For groups with the indices m as M1 to M−1 (e.g. group 0 to group 4), the group with index m includes K2 (which is 5) CBs with indices M1·K1+(m−M1)·K2+k, wherein k=0, 1, . . . , K2−1 (which is 4). That is, the group 0 includes 5 CBs with indices 0, 1, 2, 3, 4. The group 1 includes 5 CBs with indices 5, 6, 7, 8, 9. The group 2 includes 5 CBs with indices 10, 11, 12, 13, 14. The group 3 includes 5 CBs with indices 15, 16, 17, 18, 19.
For different cases, the number of filler bits may be different.
For example, N (the maximum number of CBGs per transport block) is 4, C (the number of available bits for carrying the second information) is 2, C1 (the number of CBs per transport block is 8. M=min(N, C)=min(4, 2)=2; M1=mod(C1, M)=mod(8, 2)=0;
Since M1=0, M1−1=−1, the case of “the groups with the indices m as 0 to M1−1” is not considered. For groups with the indices m as M1 to M−1 (e.g. group 0 to group 1), the group 0 (numbered as New_CBG #0) includes 4 CBs (e.g. CB #0 to CB #3). The group 1 (numbered as New_CBG #1) includes 4 CBs (e.g. CB #4 to CB #7). In response to the first information 1411 comprises the NACK, the second information 1412 may further comprise HARQ-ACK feedback for a group of CBs. It is assumed that CB #2 is not correctly decoded. That means that New_CBG #0 is not correctly decoded. Accordingly, {0, 1} is filled as the second information 1412 in the codebook 1410. The first bit in the second information 1412 represents HARQ-ACK feedback of New_CBG #0, and the second bit in the second information 1412 represents HARQ-ACK feedback of New_CBG #1.
To sum up, embodiments of the disclosure provide a method for performing a HARQ transmission at the UE. In the above embodiments, effective information is filled in the space that was originally filled with NACK, thereby improving the transmission efficiency and radio resource utilization. Therefore, the disclosure improves the transmission efficiency and radio resource utilization.
It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the disclosure covers modifications and variations provided that they fall within the scope of the following claims and their equivalents.
This application claims the priority benefit of U.S. provisional application Ser. No. 63/294,852, filed on Dec. 30, 2021. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
Number | Date | Country | |
---|---|---|---|
63294852 | Dec 2021 | US |