Apparatus, method and computer program product for HARQ buffer size reduction
View Patent ↗Apparatus, methods and computer program products implement HARQ buffer size reduction by storing successfully received blocks of a multi-block signal in a code block buffer and only storing unsuccessfully received blocks of the multi-block signal in the HARQ buffer. As HARQ retransmissions of the signal occur, previous successfully received blocks are discarded. Blocks that were not successfully received in one or more previous signals but are successfully received in a HARQ retransmission are saved in the code block buffer. The process may continue until all blocks of the multi-block signal have been successfully decoded received and stored in the code block buffer. The successfully received blocks of the multi-block signal are then passed to higher layers.
1. An apparatus comprising:
a processor;
a memory including computer program code, where the memory and computer program code are configured, with the processor, to cause the apparatus to receive communications in a wireless communications network, wherein the communications comprise multi-block original signals and retransmission signals;
where the processor is configured to decode an original signal; to determine whether the original signal was received correctly and when it is determined that only a portion of the original signal was received correctly to save blocks corresponding to the correctly-received portion in a first buffer as hard bits and to save remaining blocks corresponding to an incorrectly received portion in a second buffer; to receive a retransmission signal; to decode only that portion of the retransmission which corresponds to the incorrectly-received portion of the original signal and to discard a portion which corresponds to the previous correctly received portion; to determine whether blocks corresponding to the decoded, retained portion have been correctly received; for blocks that have been received correctly to place the correctly received blocks in the first buffer and for blocks that have been incorrectly received to place the incorrectly received blocks in the second buffer; to continue receiving and performing operations on retransmitted signals until all the blocks have been correctly received; and when all blocks have been correctly received, to pass the correctly received blocks to a higher layer.
2. The apparatus of claim 1 wherein the wireless communications system is an EUTRAN wireless communications system.
3. The apparatus of claim 1 wherein the retransmission is a hybrid automatic repeat request retransmission.
4. The apparatus of claim 1 wherein the first buffer is a hybrid automatic repeat request buffer.
5. The apparatus of claim 1 wherein the second buffer is a code block buffer.
6. The apparatus of claim 1 wherein the first buffer and second buffer comprise separate portions of a larger buffer.
7. The apparatus of claim 6 wherein the larger buffer comprises a single memory device.
8. The apparatus of claim 1 wherein the hard bits are compressed.
9. The electronic device apparatus of claim 1 wherein incorrectly received blocks are stored as soft bits in the second buffer.
10. The apparatus of claim 9 wherein the soft bits comprises integers.
11. A non-transitory computer readable medium storing a program of machine-readable instructions executable by a digital processing apparatus, where execution of said instructions results in performance of operations that comprise:
receiving a multi-block signal; decoding blocks comprising the multi-block signal; determining whether all blocks have been received correctly;
when all blocks have been received correctly, placing the decoded blocks in a decode buffer and passing the decoded blocks to a higher layer; and when all blocks have not been received correctly, determining which blocks have been received correctly;
for blocks that have been received correctly placing the correctly received blocks in a first buffer as hard bits and the incorrectly received blocks in a second buffer;
receiving a retransmission of the received signal; decoding the retransmitted signal;
discarding blocks from the retransmitted signal corresponding to previous correctly received blocks; determining whether the remaining blocks have been correctly received;
for blocks that have been received correctly placing the correctly received blocks in the first buffer and the incorrectly received blocks in the second buffer; continuing to receive and perform operations on retransmitted signals until all the blocks have been correctly received; and
when all blocks have been correctly received, passing the correctly received blocks to the higher layer.
12. The non-transitory computer readable medium of claim 11 wherein the wireless communications system is an EUTRAN wireless communications system.
13. The non-transitory computer readable medium of claim 11 wherein the retransmission is a hybrid automatic repeat request retransmission.
14. The non-transitory computer readable medium of claim 11 wherein the first buffer is a hybrid automatic repeat request buffer.
15. The non-transitory computer readable medium of claim 11 wherein the second buffer is a code block buffer.
16. A method comprising:
at an electronic device operative in a wireless communications system, receiving a multi-block signal;
decoding blocks comprising the multi-block signal;
determining whether all blocks have been received correctly;
when all blocks have been received correctly,
placing the decoded blocks in a decode buffer and passing them to a higher layer; and
when all blocks have not been received correctly,
determining which blocks have been received correctly; for blocks that have been received correctly placing the correctly received blocks in a first buffer as hard bits and the incorrectly received blocks in a second buffer;
receiving a retransmission of the received signal; decoding the retransmitted signal; discarding blocks from the retransmitted signal corresponding to previous correctly received blocks;
determining whether the remaining blocks have been correctly received; for blocks that have been received correctly placing the correctly received blocks in the first buffer and the incorrectly received blocks in the second buffer;
continuing to receive and perform operations on retransmitted signals until all the blocks have been correctly received; and
when all blocks have been correctly received, passing the correctly received blocks to the higher layer.
17. The method of claim 16 wherein the wireless communications system is an EUTRAN wireless communications system.
18. The method of claim 17 wherein the retransmission is a hybrid automatic repeat request retransmission.
19. The method of claim 17 wherein the first buffer is a hybrid automatic repeat request buffer.
20. The method of claim 17 wherein the second buffer is a code block buffer.
21. Apparatus comprising:
a processor;
a memory including computer program code, where the memory and computer program code are configured, with the processor, to cause the apparatus to receive communications that comprise multi-block original signals and retransmission signals;
to decode an original signal;
to determine whether the original signal was received correctly and when it is determined that only a portion of the original signal was received correctly to save blocks corresponding to the correctly-received portion in a first buffer as hard bits and to save remaining blocks corresponding to an incorrectly received portion in a second buffer;
to receive a retransmission signal; to decode only that portion of the retransmission which corresponds to the incorrectly-received portion of the original signal and to discard a portion which corresponds to the previous correctly received portion; to determine whether blocks corresponding to the decoded, retained portion have been correctly received;
for blocks that have been received correctly to place the correctly received blocks in the first buffer and for blocks that have been incorrectly received to place the incorrectly received blocks in the second buffer;
to continue receiving and performing operations on retransmitted signals until all the blocks have been correctly received; and
when all blocks have been correctly received, to pass the correctly received blocks to a higher layer.
22. The apparatus of claim 21 wherein the apparatus further comprises an integrated circuit.