SINR analysis of FFH/OFDM over frequency selective Rayleigh fading channel
Ahmet Oturak, Ertan Ozturk
article (Uluslararası, Hakemli) | Yazar(lar): Ahmet Oturak, Ertan Ozturk | Yıl: 2016 | Dergi/Kurum: WIRELESS COMMUNICATIONS & MOBILE COMPUTING | İndeks: WOS.SCI | DOI: 10.1002/wcm.2756 | Anahtar Kelimeler: FFH, OFDM, MMSE, ZF, SC-FDE, Rayleigh fading — Özet: Fast frequency hopping/orthogonal frequency division multiple
Fast frequency hopping/orthogonal frequency division multiplexing (FFH/OFDM) has been previously proposed to achieve frequency diversity over frequency selective channels. However, the performances of the FFH/OFDM scheme have been usually calculated using simulations over empirical channel models in earlier works. The main aim of this paper is to theoretically expose the diversity of the FFH/OFDM signal over statistical models, specifically Rayleigh distributed, for frequency selective fading channels. In order to achieve this aim, we first derive the decision variables and the signal-to-interference noise ratios of the FFH/OFDM signal at the output of minimum mean square error and zero forcing receivers. For various levels of quadrature amplitude modulation used in FFH/OFDM, the performances are calculated and validated via simulations. The results show that FFH/OFDM in case of zero forcing equalization does not provide any diversity gain even over a frequency selective channel. However, in case of minimum mean square error equalization, it brings significant diversity gain at high signal-to-noise ratio (SNR) values with the rise of number of sub-carriers. Moreover, the FFH/OFDM with four quadrature amplitude modulation scheme provides better performance than that of the conventional OFDM even at low SNR values, as well as a significant diversity gain at high SNR values. Copyright (c) 2016 John Wiley & Sons, Ltd.