Frame transmission system and method of interference alignment and controlling in multi-cell random access network

Patent metadata

Field	Value
Publication number	US-9843949-B2
Application number	US-201514744821-A
Country	US
Kind code	B2
Filing date	Jun 19, 2015
Priority date	Jun 20, 2014
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

Provided is a frame transmission method of interference alignment (IA) and controlling, the method including calculating a channel matrix of a basic service set (BSS) by measuring channel information between an access point and a user terminal, performing singular value decomposition (SVD) based on the calculated channel matrix, selecting a beamforming vector in consideration of an interference amount associated with another access point based on the SVD performed by the channel matrix, and calculating a leakage interference (LIF) value based on the selected beamforming vector.

First claim

What is claimed is:

1. A frame transmission method of interference alignment (IA) and controlling, the method comprising:
receiving a contention window (CW) value broadcasted by an access point;
setting a backoff counter based on the received CW value; and
generating a leakage interference (LIF) value related to an access point monitored for a predetermined period of time and performing a backoff by setting the backoff counter when a channel is in an idle state,
wherein the CW value is set at the access point based on a first throughput obtained from a packet that arrives in a desired signal space and a second throughput to be obtained through a multiple-packet recovery using a user terminal performing simultaneous transmissions throughout a system.

2. The method of claim 1 , wherein the performing of the backoff comprises:
dividing a range of cumulative distribution function (CDF) values based on the CW value;
calculating the LIF value based on a channel condition during a transmission attempt;
calculating the CDF values corresponding to the calculated LIF value; and
selecting the backoff counter based on the calculated CDF values, the backoff counter being selected according to a channel characteristic based on the LIF value.

3. The method of claim 1 , further comprising: decreasing the selected backoff counter by 1 for each backoff slot and attempting a packet transmission through a user terminal of which the backoff counter is to be 0.

4. The method of claim 1 , further comprising: decreasing the backoff counter for each backoff slot and suspending the backoff when a user terminal attempts a packet transmission.

5. The method of claim 1 , wherein the CW value is set as a constant based on a reciprocal value to maximize a sum of the first throughput and the second throughput.

Assignees

• Electronics & Telecommunications Res Inst

Inventors

• Oh Jin Hyung
• Jung Bang Chul
• Jin Hu
• Song Myung Sun

Classifications

• H04B7/06952

  Selecting one or more beams from a plurality of beams, e.g. beam training, management or sweeping · CPC title

• H04W74/0833

  Random access procedures, e.g. with 4-step access · CPC title

• H04W74/006

  in the downlink, i.e. towards the terminal · CPC title

• H04W24/08 Primary

  Testing, {supervising or monitoring} using real traffic · CPC title

• H04W24/02 Primary

  Arrangements for optimising operational condition · CPC title