DocumentCode :
3074813
Title :
Exploiting Interference Alignment in Multi-Cell Cooperative OFDMA Resource Allocation
Author :
Da, Bin ; Zhang, Rui
Author_Institution :
ECE Dept., Nat. Univ. of Singapore, Singapore, Singapore
fYear :
2011
fDate :
5-9 Dec. 2011
Firstpage :
1
Lastpage :
5
Abstract :
This paper studies cooperative resource allocation schemes for the inter-cell interference control in multi-cell orthogonal frequency division multiple access (OFDMA) systems. For the purpose of exposition, the downlink transmission in a simplified three-cell system is examined. It is assumed that all cells simultaneously access the same frequency band using OFDMA, which corresponds to a universal frequency reuse in cellular systems. Unlike the conventional approach that treats subcarriers as separate dimensions for user scheduling and power allocation in OFDMA, the paper exploits the interference alignment (IA) technique to formulate a new cooperative resource allocation scheme for multi-cell OFDMA by incorporating the frequency-domain precoding over parallel subcarriers. The joint optimization of frequency-domain precoders via IA, subcarrier user selection and power allocation for all cells is then investigated to maximize the system sum-throughput. Numerical results for a symmetric channel setup reveal that the IA-based scheme achieves notable throughput gains over the traditional scheme without frequency-domain precoding only when the inter-cell interference link has a comparable strength as the direct signal link, and the direct-link signal-to-noise ratio (SNR) is sufficiently high. Motivated by this observation, two hybrid schemes are proposed to exploit the benefits of both traditional and IA-based schemes, for practical cellular systems with heterogenous channel conditions.
Keywords :
OFDM modulation; cellular radio; cooperative communication; interference (signal); interference suppression; precoding; radio links; resource allocation; cellular system; cooperative resource allocation; direct link signal to noise ratio; downlink transmission; frequency domain precoders; frequency domain precoding; heterogenous channel condition; intercell interference control; intercell interference link; interference alignment; multicell cooperative OFDMA resource allocation; multicell orthogonal frequency division multiple access system; parallel subcarriers; power allocation; symmetric channel setup; three-cell system; universal frequency reuse; user scheduling; Downlink; Frequency domain analysis; Interference; Resource management; Signal to noise ratio; Throughput; Vectors;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Global Telecommunications Conference (GLOBECOM 2011), 2011 IEEE
Conference_Location :
Houston, TX, USA
ISSN :
1930-529X
Print_ISBN :
978-1-4244-9266-4
Electronic_ISBN :
1930-529X
Type :
conf
DOI :
10.1109/GLOCOM.2011.6133870
Filename :
6133870
Link To Document :
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