Spectrally Efficient Multi-Carrier Modulation Using Gabor Transform

Shravan Sriram, Naveenkumar Vijayakumar, P. Aditya Kumar, Akash S. Shetty, V. P. Prasshanth, K. A. Narayanankutty

Department of Electronics and Communication Engineering, Amrita School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, India.

DOI: 10.4236/wet.2013.42017                

Abstract

Non Orthogonal Frequency Division Multiplexing (NOFDM) systems make use of a transmission signal set which is not restricted to orthonormal bases unlike previous OFDM systems. The usage of non-orthogonal bases generally results in a trade-off between Bit Error Rate (BER) and receiver complexity. This paper studies the use of Gabor based on designing a Spectrally Efficient Multi-Carrier Modulation Scheme. Using Gabor Transform with a specific Gaussian envelope; we derive the expected BER-SNR performance. The spectral usage of such a NOFDM system when affected by a channel that imparts Additive White Gaussian Noise (AWGN) is estimated. We compare the obtained results with an OFDM system and observe that with comparable BER performance, this system gives a better spectral usage. The effect of window length on spectral usage is also analyzed.

Keywords

Non-Orthogonal Frequency Division Multiplexing (NOFDM); Spectrally Efficient Frequency Division Multiplexing (SEFDM); Gabor Transform; OFDM; Reisz Bases; Multi Carrier Modulation (MCM)

Conflicts of Interest

The authors declare no conflicts of interest.

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