Tongxin xuebao (Jan 2007)

Channel estimation method for MIMO-OFDM systems based on pilots and modified Kalman filter

  • SONG Tie-cheng,
  • YOU Xiao-hu,
  • SHEN Lian-feng,
  • SONG Xiao-jin

Abstract

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A combined channel estimation method of time-frequency-selective fading channels in MIMO-OFDM systems was proposed.The time-varying channel was modeled as an autoregressive(AR) process and a low-dimensional Kalman filter based on pilots was used to estimate the AR parameters,and the LS(least square) algorithm was adopted to track the time-varying channel fading factors.The Kalman estimator explored the time-domain correlation of the channel,and a minimum mean square error(MMSE) combiner was used to modify the Kalman estimates.The proposed solution could reduce the complexity of the high-dimensional Kalman filter and track the channel both in frequency and time domains.The simulation results show that this method improves the LS estimates and has a comparable performance to the com-plex high-dimensional Kalman channel estimation method.

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