On the Performance Comparison of Non-ideal Single-Carrier and Multi-Carrier Waveforms over Wide-band HF Channels

The purpose of this paper is to quantify the effects of Carrier Frequency Offset (CFO), Symbol Timing Offset (STO) and Phase Noise in coded Orthogonal Frequency Division Multiplexing (OFDM) and coded Single Carrier Frequency Domain Equalization (SC-FDE) systems and to compare their relative sensitivities in wide-band HF channel model. In mobile communication systems where multi-path propagation occurs channel estimation and equalization is additionally necessary. Furthermore a non-ideal local oscillator generally is misaligned with the operating frequency at the receiver and this causes carrier frequency offset (CFO). Therefore in coded SC-FDE and coded OFDM systems; a very efficient, low complex frequency domain channel estimation and equalization is implemented in this paper. Also Cyclic Prefix (CP) based synchronization synchronizes the clock and carrier frequency offset. Proposed models show that, one of the most powerful code, Turbo Code, enables to utilize the full frequency diversity available in the channel. The BER performance of the computer simulations specify that non-ideal turbo coded OFDM has better performance with greater diversity than non-ideal turbo coded SC-FDE system in wide-band HF channel.