Large deviation delay analysis of queue-aware multi-user MIMO systems with multi-timescale mobile-driven feedback

Patent metadata

Field	Value
Publication number	US-9755711-B2
Application number	US-201414253799-A
Country	US
Kind code	B2
Filing date	Apr 15, 2014
Priority date	Sep 9, 2013
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A subset of mobile device candidates in a multi-input multi-output (MIMO) channel of network devices is selected for having a feedback priority among a set of mobile device candidates. The selection is based on a set of queue state information of a plurality of mobile device queues for transmitter and receiver devices of the MIMO channel in a multi-user MIMO network. A portion of the subset of mobile device candidates can be selected by a scheduling component of the system. Communications on the MIMO channels can be scheduled to the portion of the subset of mobile device candidates based on the feedback comprising channel state information and on the queue state information of the plurality of mobile device queues.

First claim

What is claimed is:

1. A system comprising:
a memory storing executable components; and
a processor configured to execute the executable components, the executable components comprising:
a feedback filter component configured to determine a subset of mobile device candidates having a feedback priority from among a set of mobile device candidates based on a set of queue state information of a plurality of transmitters and receivers of a plurality of mobile devices communicatively coupled in a multiple input multiple output channel;
a random beamforming component configured to transmit, at a set of time slots, a communication that identifies the subset of mobile device candidates prior to receiving a set of channel state information corresponding to the subset of mobile device candidates, using random beamforming that facilitates a near-orthogonal data stream transmission to the subset of mobile device candidates; and
a scheduling component configured to select a portion of the subset of mobile device candidates and to schedule communications with the portion of the subset of mobile device candidates, based on feedback comprising the set of channel state information corresponding to the subset of mobile device candidates and the set of queue state information of the plurality of mobile devices.

2. The system of claim 1 , wherein the scheduling component is further configured to select the portion of the subset of mobile device candidates determined to have a signal-to-interference-plus-noise ratio that satisfies a defined condition from among the set of mobile device candidates.

3. The system of claim 1 , wherein the near-orthogonal data stream transmission to the subset of mobile device candidates comprises random orthogonal vectors generated in accordance with an isotropic distribution of the near-orthogonal data stream.

4. The system of claim 1 , wherein the feedback filter component is further configured to determine user feedback probabilities at a number of time slots based on a set of user queuing backlogs and communicate the user feedback probabilities to enable the subset of mobile device candidates to feedback the set of channel state information according to the user feedback probabilities that independently correspond to the subset of mobile device candidates.

5. The system of claim 4 , wherein the scheduling component is further configured to receive the feedback according to the user feedback probabilities via a noiseless feedback channel and at a defined time slot of the time slots.

6. The system of claim 1 , wherein the scheduling component is further configured to schedule a set of transmissions for the portion of the subset of mobile device candidates to communicate among the plurality of transmitters and receivers of the multiple input multiple output channel concurrently according to a spatial degree of freedom, independent of global channel state information.

7. The system of claim 1 , wherein the scheduling component is further configured to receive the feedback in response to satisfaction of a stochastic feedback filtering condition that reduces a feedback cost of the system by conditionally allowing the portion of the subset of mobile device candidates to provide the feedback.

8. The system of claim 1 , wherein the feedback further comprises selected beam indices and effective signal-to-interference-plus-noise ratios that correspond to the selected beam indices, from the subset of mobile device candidates.

9. The system of claim 8 , wherein the scheduling component is further configured to select the portion of the subset of mobile device candidates from among the subset of mobile device candidates based on the selected beam indices and the effective signal-to-interference-plus-noise ratios that are greater than the effective signal-to-interference-plus-noise ratios of other mobile device candidates of the subset of mobile device candidates.

10. The system of claim 1 , wherein the communication enables the subset of mobile device candidates to communicate the feedback while preventing other mobile devices of the set of mobile device candidates from communicating the feedback.

11. The system of claim 10 , wherein the feedback filter component is further configured to determine the subset of mobile device candidates by selecting mobile device candidates from the set of mobile device candidates that are determined to satisfy a defined condition associated with a queue delay length.

12. The system of claim 1 , wherein the scheduling component is further configured to select the portion of the subset of mobile device candidates based on a determination of a queue delay length associated with the plurality of mobile device queues.

13. The system of claim 1 , wherein the feedback filter component is further configured to determine the subset of mobile device candidates by defining a queue stability and a queue stability region among arrival data vectors for the plurality of mobile devices.

14. The system of claim 13 , wherein the executable components further comprise:
a throughput feedback component configured to generate a feedback probability vector that stabilizes the arrival data vectors from the feedback within the queue stability region to achieve an increased throughput.

15. The system of claim 1 , wherein the executable components further comprise:
a feedback component configured to determine a user feedback amount enabling a determination of the subset of mobile device candidates.

16. A method, comprising:
determining a subset of mobile device candidates from among a set of mobile device candidates based on queue state information of a plurality of mobile device queues for a plurality of transmitters and receivers communicatively coupled in a multiple input multiple output channel;
transmitting a communication comprising a random beam that supports a near-orthogonal data stream to the subset of mobile device candidates that initiates feedback comprising channel state information from the subset of mobile device candidates in the plurality of mobile device queues; and
selecting a portion of the subset of mobile device candidates for scheduling communications via the multiple input multiple output channel.

17. The method of claim 16 , further comprising:
receiving the feedback from the subset of mobile device candidates in the plurality of mobile device queues.

18. The method of claim 16 , further comprising generating the random beam that supports near-orthogonal data stream transmissions to the subset of mobile device candidates in accordance with an isotropic distribution prior to obtaining knowledge of a global channel state information for the set of mobile device candidates.

19. The method of claim 16 , further comprising:
determining a set of user backlogs for the set of mobile device candidates for the plurality of mobile device queues that comprises a set of state-dependent coupled queues; and
sending a set of user feedback probabilities associated with the set of mobile device candidates as a function of the set of user backlogs.

20. The method of claim 19 , further comprising:
in response to a stochastic feedback filtering condition being satisfied, receiving a set of effective signal-to-interference-plus noise ratios corresponding to a set of beams on receive antennas of the subset of mobile device candidates.

21. The method of claim 20 , further comprising:
scheduling the portion of the subset of mobile device candidates to transmit at the set of beams

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Lau Vincent Kin Nang
• Chen Junting

Classifications

• H04W72/54

  based on quality criteria · CPC title

• H04W72/12

  Wireless traffic scheduling · CPC title

• H04L25/0204

  of multiple channels · CPC title

• H04W72/52

  based on load · CPC title

• H04B7/0452

  Multi-user MIMO systems · CPC title