Improving scattered pilot channel estimation by sector selection on FDD MIMO/OFDM systems

This paper proposes the combined scheme with the scattered pilot channel estimation and the sector antenna selection to improve throughput and BER performance. Even in the frequency division duplex (FDD) system, the optimal transmission sector can be selected by using up and down link correlation without the feedback information (FBI). Sector selection can alleviate a frequency selectivity by eliminating the number of incoming reflected paths and accordingly the coherence bandwidth can be enlarged. Exploiting this feature, channel estimation accuracy can be kept even though reducing the number of pilot symbols in frequency domain. This paper introduces the high time resolution carrier interferometry (HTRCI) and the simple linear interpolation (SLI) as the scattered pilot channel estimation and evaluates their achievable throughput performance. Computer simulation on 2×2 MIMO/OFDM sector selection system disclosed that HTRCI and SLI can improve BER and throughput performance. Particularly, maximum throughput is improved by 7.5% in the case of HTRCI.