Iterative channel estimation using joint zero padding and nonzero padding for TDS-OFDM systems

This paper focuses on the use of guard intervals (GIs) between successive symbols for iterative channel estimation (CE) in a time domain synchronous orthogonal frequency division multiplexing (TDS-OFDM) system. A hybrid of zero padding (ZP) and nonzero padding (NZP) frame structures is proposed to create an energy efficient scheme that can maintain accurate CE as well as a low transmission bit error rate (BER). The proposed hybrid scheme, i.e., joint zero padding-nonzero padding (ZP-NZP) scheme, is tested in Rayleigh fading channel environments using computer simulations. The results show that, for the same BER performance, the proposed joint ZP-NZP scheme outperforms the existing NZP scheme on the basis of the reduction in the required signal-to-noise ratio (SNR) while its CE results are comparable to the existing NZP scheme.