Research Repository

Investigation of a Semidefinite Programming detection for a spectrally efficient FDM system

Kanaras, Ioannis and Chorti, Arsenia and Rodrigues, Miguel and Darwazeh, Izzat (2009) Investigation of a Semidefinite Programming detection for a spectrally efficient FDM system. In: 2009 IEEE 20th International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC 2009), 2009-09-13 - 2009-09-16.

Full text not available from this repository.

Abstract

Recent years have witnessed some interest in Spectrally Efficient Frequency Division Multiplexing (SEFDM) communications systems, where subcarrier orthogonality is intentionally violated to improve the spectral efficiency at the expense of system complexity. This paper investigates reliable polynomial-time hard detection techniques for SEFDM systems, by relaxing the optimal combinatorial Maximum Likelihood (ML) detection to a Semidefinite Program (SDP). SDP can be solved in almost cubic complexity over the number of the SEFDM subcarriers, N. However, the relaxation results into a degradation of the system error performance. In particular, we study the effect of the number of SEFDM subcarriers, N, and the subcarrier separation, Δf, on the SDP relaxation gap in the presence of Additive White Gaussian Noise (AWGN). We find that as N increases and/or Δf decreases, the SDP estimate gradually diverges from the optimal solution. To overcome this problem, we propose the use of a boxed ML procedure around the SDP estimate. We show by simulation that the SDP-ML combination approximates the optimum detection for N ≤ 32 subcarriers and up to 20% of bandwidth reduction with respect to an equivalent Orthogonal FDM (OFDM). Our SDP results show a small error penalty when compared to optimal Sphere Decoders (SD), whose computational effort is random and noise dependant, and thereby indicate that our proposed technique is useable in practical SEFDM systems with a moderate number of subcarriers. ©2009 IEEE.

Item Type: Conference or Workshop Item (Paper)
Additional Information: Published proceedings: IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC
Subjects: Q Science > QA Mathematics > QA75 Electronic computers. Computer science
Divisions: Faculty of Science and Health
Faculty of Science and Health > Computer Science and Electronic Engineering, School of
SWORD Depositor: Elements
Depositing User: Elements
Date Deposited: 15 Jul 2015 20:07
Last Modified: 15 Jan 2022 00:37
URI: http://repository.essex.ac.uk/id/eprint/9170

Actions (login required)

View Item View Item