INTERFERENCE ALIGNMENT FOR PARTIALLY CONNECTED CELLULAR NETWORKS

• US 20140376655A1
• Filed: 02/21/2013
• Published: 12/25/2014
• Est. Priority Date: 02/27/2012
• Status: Active Grant

• Current Assignee: Hong Kong University of Science and Technology
• Original Assignee: Hong Kong University of Science and Technology
• Inventors: Ruan, Liangzhong, Lau, Vincent Kin Nang, Rao, Xiongbin
• Granted Patent: US 10,158,405 B2
• Time in Patent Office: Days
• US Class Current: 375/267
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/046 taking physical layer constraints into account
• CPC Class Codes: H04L 1/06 using space diversity

Abstract

Interference alignment for a multiple-input multiple-output communications network with partial connectivity is provided. A method is provided that includes determining assignments for data streams transmitted in the multiple-input multiple-output communications network. The method also includes suppressing inter-cell interference and suppressing intra-cell interference. Also provided is inter-cell/intra-cell decomposition and exploitation of partial connectivity in a multiple-input multiple-output communications network. The multiple-input multiple-output communications network can comprise three or more cells.

Claims

1. A system, comprising:

a memory to store instructions; and

a processor, communicatively coupled to the memory, that facilitates execution of the instructions to perform operations, comprising;

determining assignments for data streams transmitted to one or more devices in a multiple-input multiple-output network;

suppressing inter-cell interference; and

suppressing intra-cell interference.

2. The system of claim 1, wherein the determining the assignments comprises maximizing a sum of a function applied to the data streams.

3. The system of claim 1, wherein the determining the assignments comprises:

initializing a stream assignment policy; and

determining whether interference alignment is applicable to the data streams based on the stream assignment policy.

4. The system of claim 3, wherein the initializing comprises setting the stream assignment policy for a mobile device in communication with the multiple-input multiple-output network to be a number of data streams requested by the mobile device.

5. The system of claim 1, wherein the suppressing the inter-cell interference comprises updating intermediate precoders and decorrelators.

6. The system of claim 1, wherein the suppressing the inter-cell interference comprises updating intermediate precoders and decorrelators and the suppressing intra-cell interference comprises further adjusting the intermediate precoders.

7. The system of claim 1, wherein the one or more devices of the multiple-input multiple-output network comprise a combination of cells, user devices, and antennas.

8. The system of claim 1, wherein the one or more devices of the multiple-input multiple-output network comprises three or more cells.

9. The system of claim 1, wherein the inter-cell interference and the intra-cell interference are produced by the transmitted data streams.

10. A method, comprising:

evaluating, by a system comprising a processor, an interference alignment status of a set of communication links of a communications network, wherein the set of communication links comprises defined communication links and undefined communication links;

distinguishing, by the system, the defined communication links from the undefined communication links;

suppressing, by the system, a first interference caused by the defined communication links; and

suppressing, by the system, a second interference caused by the undefined communication links that is different from the first interference.

11. The method of claim 10, wherein the communications network is a multiple-input multiple-output communications network comprising an arbitrary number of cells, user devices, and antennas.

12. The method of claim 10, further comprising concurrently zero forcing, by the system, the first interference and the second interference.

13. The method of claim 10, where the suppressing the first interference caused by the defined communication links comprises suppressing the first interference on a per cell basis.

14. The method of claim 10, wherein the evaluating comprises determining a network device of the communications network is configured to operate with application of an interference alignment.

15. The method of claim 10, wherein the evaluating comprises determining assignments for a first set of data streams of the undefined communication links and a second set of data streams of the defined communication links, and further comprising maximizing a degree of freedom of a network device of the communications network.

16. The method of claim 15, wherein the evaluating comprises:

initializing a stream assignment policy comprising setting the stream assignment policy to be a number of streams requested by each mobile device communicating with network devices of the communications network; and

determining a practicability of interference alignment within the communications network.

17. The method of claim 15, wherein the suppressing the first interference comprises updating intermediate precoders and decorrelators and the suppressing the second interference comprises adjusting the intermediate precoders after the updating.

18. A method, comprising:

determining, by a system comprising a processor, assignments for data streams transmitted by devices in a multiple-input multiple-output network, the determining comprising maximizing a sum of a function of the data streams of the multiple-input multiple-output network;

suppressing inter-cell interference; and

suppressing intra-cell interference,

wherein the multiple-input multiple-output network comprises three or more cells.

19. The method of claim 18, wherein the suppressing inter-cell interference comprises updating intermediate precoders and decorrelators and the suppressing intra-cell interference comprises further adjusting the intermediate precoders.

20. The method of claim 18, wherein the suppressing intra-cell interference comprises suppressing the intra-cell interference on a per cell basis.