Method and apparatus for the joint design and operation of ARQ protocols with user scheduling for use with multiuser MIMO in the downlink of wireless systems

Patent metadata

Field	Value
Publication number	US-9344177-B2
Application number	US-201414466854-A
Country	US
Kind code	B2
Filing date	Aug 22, 2014
Priority date	Aug 26, 2009
Publication date	May 17, 2016
Grant date	May 17, 2016

Abstract

A method and apparatus is disclosed herein for performing wireless communication. In one embodiment, the apparatus comprises a processing unit to run a scheduling selection algorithm to update user terminal scheduling weights in response to scheduling feedback transmitted by a plurality of user terminals by an end of an immediately preceding scheduling event; a scheduler and precoder, responsive to the updated user terminal scheduling weights generated by the scheduling algorithm and channel estimates of user terminals, to choose a set of user terminals for scheduling and to choose precoder beams and their power for such user terminal in the set of user terminals; a plurality of precoding blocks to receive one coded ARQ block for at least one packet for each user terminal in the set and, responsive to the precoder beams, to generate precoded data, where the one coded ARQ block is one of a plurality of ARQ blocks generated for a single packet and being generated using a single ARQ scheme for such each user terminal; and a transmitter to transmit the precoded data using MIMO transmission.

First claim

We claim:

1. A method comprising:
generating a plurality of ARQ blocks for a single packet that is to be sent to one user terminal of a plurality of user terminals;
updating user terminal scheduling weights in response to scheduling feedback transmitted by the plurality of user terminals by an end of an immediately preceeding scheduling event;
scheduling a set of the plurality of user terminals for a scheduling slot based on the updated user terminal scheduling weights;
selecting precoder beams and their power for each user terminal in the set;
generating precoded data from one of the ARQ blocks using a selected precoded beam and its selected power selected for the one user terminal for the scheduling slot; and
transmitting the precoded data as part of a MIMO transmission process.

2. The method defined in claim 1 wherein the plurality of ARQ blocks are generated independently of scheduling and precoding.

3. The method defined in claim 1 wherein generating the plurality of ARQ blocks is performed using a set of parameters associated with the one user terminal, and wherein the set of parameters are independent of knowledge of the instantaneous channel.

4. The method defined in claim 1 wherein generating the plurality of ARQ blocks comprises:
receiving information bits for the one user terminal;
splitting the received information bits into a plurality of packets based on an ARQ block coding rate; and
applying an ARQ block generator process to each of the plurality of packets based on a signaled ARQ scheme, and coding and modulation parameters to produce a plurality of ARQ blocks for each of the plurality of packets, including the plurality of ARQ blocks for the single packet, wherein each of the ARQ blocks comprises coded samples.

5. The method defined in claim 1 wherein transmitting the precoded data occurs such that the ARQ blocks for the packet are scheduled and transmitted over distinct transmission slots (or over transmission slots corresponding to distinct scheduling events).

6. The method defined in claim 1 further comprising selecting the one ARQ block for transmission by:
determining whether the one user terminal is scheduled;
if the one user terminal is scheduled, determining if feedback information from the one user terminal for a previous one of the ARQ blocks for the packet is an acknowledgement (ACK) signal, selecting an ARQ block for another packet for transmission if the feedback information is an ACK signal; selecting the one ARQ block for transmission if the feedback information is a negative acknowledgement (NACK) signal, the plurality of ARQ blocks being a sequence of ARQ blocks to be transmitted in sequential order, and the one ARQ block being the next in the sequential order the ARQ block to be transmitted.

7. An article of manufacture having one or more computer readable storage media storing instructions thereon which, when executed by a system, cause the system to perform a method comprising:
generating a plurality of ARQ blocks for a single packet that is to be sent to one user terminal of a plurality of user terminals;
updating user terminal scheduling weights in response to scheduling feedback transmitted by the plurality of user terminals by an end of an immediately preceeding scheduling event;
scheduling a set of the plurality of user terminals for a scheduling slot based on the updated user terminal scheduling weights;
selecting precoder beams and their power for each user terminal in the set;
generating precoded data from one of the ARQ blocks using a selected precoded beam and its selected power selected for the one user terminal for the scheduling slot; and
transmitting the precoded data as part of a MIMO transmission process.

8. The article of manufacture defined in claim 7 wherein the plurality of ARQ blocks are generated independently of scheduling and precoding.

9. The article of manufacture defined in claim 7 wherein generating the plurality of ARQ blocks is performed using a set of parameters associated with the one user terminal, and wherein the set of parameters are independent of knowledge of the instantaneous channel.

10. The article of manufacture defined in claim 7 wherein generating the plurality of ARQ blocks comprises:
receiving information bits for the one user terminal; splitting the received information bits into a plurality of packets based on an ARQ block coding rate; and
applying an ARQ block generator process to each of the plurality of packets based on a signaled ARQ scheme, and coding and modulation parameters to produce a plurality of ARQ blocks for each of the plurality of packets, including the plurality of ARQ blocks for the single packet, wherein each of the ARQ blocks comprises coded samples.

11. The article of manufacture defined in claim 7 wherein transmitting the precoded data occurs such that the ARQ blocks for the packet are scheduled and transmitted over distinct transmission slots (or over transmission slots corresponding to distinct scheduling events).

12. The article of manufacture defined in claim 7 wherein the method further comprises selecting the one ARQ block for transmission by:
determining whether the one user terminal is scheduled;
if the one user terminal is scheduled, determining if feedback information from the one user terminal for a previous one of the ARQ blocks for the packet is an acknowledgement (ACK) signal, selecting an ARQ block for another packet for transmission if the feedback information is an ACK signal;
selecting the one ARQ block for transmission if the feedback information is a negative acknowledgement (NACK) signal, the plurality of ARQ blocks being a sequence of ARQ blocks to be transmitted in sequential order, and the one ARQ block being the next in the sequential order the ARQ block to be transmitted.

Assignees

• Shirani-Mehr Hooman
• Papadopoulos Haralabos C
• Ramprashad Sean A
• Caire Giuseppe
• Ntt Docomo Inc

Inventors

• Shirani-Mehr Hooman
• Papadopoulos Haralabos C
• Ramprashad Sean A
• Caire Giuseppe

Classifications

• H04W72/12

  Wireless traffic scheduling · CPC title

• H04L1/1819

  with retransmission of additional or different redundancy · CPC title

• H04B7/0647 Primary

  Variable feedback rate · CPC title

• H04L1/0025

  Transmission of mode-switching indication · CPC title

• H04B7/0452

  Multi-user MIMO systems · CPC title