Method and apparatus for subchannel assignment for suppressing interantenna interference in OFDMA system

Abstract

Disclosed is a method and an apparatus for subchannel assignment for suppressing inter-antenna interference in an Orthogonal Frequency Division Multiplexing Access (OFDMA) system based distributed wireless communication system equipped with antennas that are randomly distributed in a geographical manner and can simultaneously communicate with multiple Subscriber Stations (SSs). The method includes selecting and obtaining access to distributed antennas which satisfy the data transmission rate that an SS requires and with which the SS can communicate; re-queuing a distributed antenna having themaximum transmitted power within the same cell in high priority; and assigning subchannels to the relevant distributed antennas in an order from the relevant distributed antenna having the high priority.

Description

Technical field [0001] The present invention relates to an Orthogonal Frequency Division Multiplexing Access (OFDMA) communication system, and more particularly, to a method and device for sub-channel allocation for suppressing and minimizing inter-antenna interference in an OFDMA system. Background technique [0002] With the increase in user demand related to Internet services, the demand for a communication system that can effectively provide Internet services is increasing. An existing communication network mainly used for voice services has been developed, but the disadvantage is that the existing communication system has a relatively narrow data transmission bandwidth and requires an expensive cost for its use. [0003] In order to solve or correct such defects, the OFDM scheme, which is a representative example of broadband wireless access schemes, is being studied. [0004] The OFDM scheme corresponds to a typical transmission scheme using multiple carriers and a scheme o...

AI Technical Summary

Problems solved by technology

Existing communication networks have been developed primarily for voice services, but have the disadvantage that existing communication systems have a relatively narrow bandwidth for data transmission and are expensive to use

[0018] 2. All sub-channels are assigned to cells only once

[0020] However, if all subchannels are developed per antenna as described above, this is the same as cellular diversity from a frequency reuse perspective, and causes inter-antenna interference similar to co-channel interference in cellular diversity

Also, if all sub-channels are developed by one remote antenna and one SS, even if the interference with another antenna is excluded, it causes a waste of bandwidth and problems such as hot spots appear

[0021] Therefore, currently, even if two antennas are sufficiently far from each other in OFDMA-based DAS, its subchannels cannot be reused

[0022] In this way, if each antenna develops all subchannels, this is the same as cellular diversity from a frequency reuse point of view, causing the problem that severe inter-antenna interference similar to co-channel interference occurs

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