Estimation of Frequency Selectivity for Ofdm Based New Generation Wireless Communication Systems
نویسندگان
چکیده
In this paper, estimation of both global (long term) and local (instantaneous) frequency selectivity and rms delay spread of wireless communication channel are investigated. A practical algorithm for averaged channel frequency correlation estimation, which is used for measuring frequency selectivity, is given. Average rms delay spread of the channel is calculated from the channel frequency correlation estimate. For measuring local frequency selectivity, channel frequency response estimate is exploited. Time domain channel impulse response is obtained by taking IFFT of the sampled channel frequency response. Optimal sampling rate of the estimated channel response is investigated. Performance of the estimates are obtained in noise limited situations. The effect of noise variance and robustness of the estimates against different channel power delay profiles is discussed for global parameter estimation. For local parameter estimation, the effect of channel estimation error is studied.
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