Wireless communication apparatus and method for HARQ buffer management

Patent metadata

Field	Value
Publication number	US-9819454-B2
Application number	US-201414568087-A
Country	US
Kind code	B2
Filing date	Dec 11, 2014
Priority date	Dec 11, 2014
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

A transmission node in a wireless communication network includes a receiving unit for receiving a set of data packets transmitted from a set of nodes in the network scheduled in one TTI, a memory unit having a number of memory blocks, each for storing a set of data packets transmitted in a separate TTI of a HARQ process. Each memory block includes sub-memory blocks, each of which is for storing a data packet transmitted from a separate UE. The transmission node further includes a processor for allocating the set of data packets to the sub-memory blocks and releasing the sub-memory blocks after one HARQ process upon receipt of the set of data packets.

First claim

The invention claimed is:

1. A transmission node in a wireless communication network, comprising:
a receiving unit for receiving a plurality of data packets transmitted from nodes in the wireless communication network, wherein in each transmission time interval (TTI), a set of the nodes are scheduled to transmit a set of data packets to the transmission node, wherein each node of the set of nodes transmits one data packet to the transmission node in one TTI;
a memory unit connected to the receiving unit, wherein the memory unit includes a first buffer and a second buffer, wherein each of the first buffer and the second buffer includes a first number of memory blocks for storing the plurality of data packets, wherein the set of data packets transmitted in a particular TTI are stored in one memory block corresponding to the particular TTI in the first buffer, wherein each of the first number of memory blocks comprises a plurality of sub-memory blocks, wherein each of the plurality of sub-memory blocks stores one data packet;
a processor connected to the memory unit, comprising:
a buffer control unit for allocating the set of data packets into the plurality of sub-memory blocks and releasing the plurality of sub-memory blocks after a first number of TTIs upon receipt of the set of data packets; and
a data processing unit for decoding the plurality of data packets; and

a transmitting unit for transmitting acknowledgment information based on a result of the decoded plurality of data packets, wherein the transmitting unit transmits a negative acknowledgement and the buffer control unit retains a sub-memory block when the data processing unit fails to decode a data packet.

2. The transmission node of claim 1 , wherein the first number is determined by a duration of a Hybrid Automatic Repeat Request process.

3. The transmission node of claim 1 , wherein when the data processing unit succeeds in decoding a data packet transmitted from a node, the transmitting unit transmits an acknowledgement of the data packet to the node, and the buffer control unit releases a sub-memory block used for storing the data packet.

4. The transmission node of claim 1 , wherein if-when the data processing unit fails to decode a data packet transmitted from a node, the transmitting unit transmits a negative-acknowledgement of the data packet to the node, and the buffer control unit retains a sub-memory block that stores the data packet for re-transmission.

5. The transmission node of claim 4 , wherein the node re-transmits the data packet upon receipt of the negative-acknowledgement.

6. The transmission node of claim 5 , wherein the data packet corresponds to a set of unique identification information available in the transmission node that indicates a node from which the data packet was transmitted and a TTI in which the data packet was transmitted.

7. The transmission node of claim 5 , wherein the buffer control unit allocates the data packet re-transmitted from the node to the sub-memory block retained for re-transmission based on unique identification information.

8. The transmission node of claim 5 , wherein the data processing unit combines the data packet re-transmitted from the node with the data packet to form a combined data packet, and the buffer control unit allocates the combined data packet to a sub-memory block corresponding to a TTI in the second buffer.

9. The transmission node of claim 1 , wherein each memory block comprises a second number of sub-memory blocks, wherein the second number is fixed and is determined by a maximum number of the set of the plurality of nodes scheduled in one TTI, and wherein a size of each of the second number of sub-memory blocks is fixed and is determined by a maximum size of a data packet transmitted by one node.

10. The transmission node of claim 9 , wherein a size of a sub-memory block is dynamically allocated according to a size of the data packet.

11. The transmission node of claim 10 , wherein the buffer control unit allocates the data packet re-transmitted from the node to the sub-memory block retained for re-transmission based on unique identification information, and the size of the data packet.

12. A method of operating a transmission node in a wireless communication network, comprising:
receiving a first set of data packets transmitted from a set of nodes in the network in a first transmission time interval (TTI), wherein each of the set of nodes transmits one data packet to the transmission node in the first TTI;
storing the first set of data packets to a memory block corresponding to the first TTI in a first buffer, wherein each of the first set of data packets is stored in a separate sub-memory block of the memory block;
decoding a first particular data packet of the first set of data packets;
transmitting a positive acknowledgement information based on a positive result of the decoding;
based on a negative result of the decoding:
transmitting a negative acknowledgement information;
retaining a sub-memory block in the first buffer in which a particular data packet is stored;
in response to a first number of transmission time intervals not having elapsed, receiving a second set of data packets in a second TTI, wherein the second set of data packets includes a second particular data packet, wherein the second particular data packet is a retransmisssion of the first particular data packet;
decoding the second particular data packet;
producing a combined data packet by combining the first particular data packet and the second particular data packet using Hybrid Automatic Repeat Request (HARQ) combining; and
storing the combined data packet in a memory block corresponding to the second TTI in a second buffer; and

releasing sub-memory blocks after the first number of TTIs upon receipt of the set data packets stored in the sub-memory blocks.

13. The method of claim 12 , wherein the first number of TTIs is determined by duration of a Hybrid Automatic Repeat Request process.

14. The method of claim 12 , wherein the step of transmitting a positive acknowledgement information includes transmitting an acknowledgement of a data packet to a node from which the data packet was transmitted and releasing a sub-memory block that stores the data packet, when the data packet is successfully decoded.

15. The method of claim 12 , wherein the step of transmitting a negative acknowledgement information includes transmitting a negative-acknowledgement of a data packet to a node from which the data packet was transmitted and retaining a sub-memory block that stores the data packet for re-transmission, when the data packet is not successfully decoded.

16. The method of claim 15 , wherein each of the first set of data packets and the second set of data packets corresponds to a set of unique identification information available in the transmission node that indicates the node from which the data packet was transmitted and a TTI in which the data packet was transmitted.

17. The method of claim 16 , further comprising receiving and allocating the second particular data packet re-transmitted from the node to the sub-memory block retained for re-transmission of the first particular data packet based on unique identification information.

18. The method of claim 12 , further comprising dynamically allocating a sub-memory block of the memory block based on a size of the first data packet.

19. The method of claim 18 , further comprising receiving and allocating the second particular data packet re-transmitted from the node to the

Assignees

• Jain Nitin
• Gupta Maneesh
• Nxp Usa Inc

Inventors

• Jain Nitin
• Gupta Maneesh

Classifications

• H04L1/1812 Primary

  Hybrid protocols; Hybrid automatic repeat request [HARQ] · CPC title

• H04L1/1835

  Buffer management · CPC title

• H04L1/1819

  with retransmission of additional or different redundancy · CPC title

• H04L1/1809 Primary

  Selective-repeat protocols · CPC title

• H04L1/1822

  involving configuration of automatic repeat request [ARQ] with parallel processes · CPC title