WET  Vol.4 No.2 , April 2013
Spectrally Efficient Multi-Carrier Modulation Using Gabor Transform
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.
Cite this paper: S. Sriram, N. Vijayakumar, P. Kumar, A. Shetty, V. Prasshanth and K. Narayanankutty, "Spectrally Efficient Multi-Carrier Modulation Using Gabor Transform," Wireless Engineering and Technology, Vol. 4 No. 2, 2013, pp. 112-116. doi: 10.4236/wet.2013.42017.

[1]   M. Rodrigues and I. Darwazeh, “A Spectrally Efficient Frequency Division Multiplexing Based Communication System,” 8th International OFDM Workshop, Hamburg, September 2003, pp. 70-74.

[2]   S. I. A. Ahmed and I. Darwazeh, “IDFT Based Transmitters for Spectrally Efficient FDM System,” London Communications Symposium, 2009.

[3]   S. Isam and I. Darwazeh, “Simple DSP-IDFT Techniques for Generating Spectrally Efficient FDM Signals,” 2010 7th International Symposium on Communication Systems Networks and Digital Signal Processing (CSNDSP), London, 21-23 July 2010, pp. 20-24.

[4]   Z. Zhang, W. Chen, Q. Liu and G. Xuan, “NOFDM System Based on Circular Conjugate Symmetry Properties of DFT,” 4th International Wireless Communications, Networking and Mobile Computing, Chongqing, 12-14 October 2008, pp. 1-4.

[5]   W. Kozek and A. F. Molisch, “Nonorthogonal Pulseshapes for Multicarrier Communications in Doubly Dispersive Channels,” IEEE Journal on Selected Areas in Communications, Vol. 16, No. 8, 1998, pp. 1579-1589. doi:10.1109/49.730463

[6]   R. Prasad, “OFDM for Wireless Communication Systems,” Artech House, Boston-London, 2004.

[7]   H. Feichtinger and T. Strohmer, “Gabor Analysis and Algorithms, Theory and Applications,” Birkhauser, Berlin, 1998. doi:10.1007/978-1-4612-2016-9

[8]   A. Kliks, A. Zalonis, I. Dagres, A. Polydoros and H. Bogucka, “PHY Abstraction Methods for OFDM and NOFDM Systems,” Journal of Telecommunication and Information Technology, No. 3, 2009, p. 116.

[9]   S. Veni and K. A. Narayanankutty, “Vison-Based Hexaganol Image Processing Using Hex-Gabor,” Springer, Berlin, 2012.

[10]   G. Acosta, “OFDM Simulation Using Matlab,” 2000.