Multiluser Decorrelating Based Long-Range Frequency-Domain Channel Transfer Function Prediction in Multicarrier DS-CDMA Systems

In this contribution, multiuser decorrelating based frequency-domain channel estimation and long range channel prediction techniques are proposed for a generalized multicarrier DS-CDMA (MC DS-CDMA) system communicating over a fast fading and frequency-selective channel. In the MC DS-CDMA system considered, the channel transfer function (CTF) is estimated in the frequency-domain with the aid of pilot symbols by invoking the multiuser decorrelating based channel estimation technique, in order to reduce the effects of both the multiuser interference (MUI) and the background noise. Then, Kalman filter assisted long-range channel prediction is carried out with the aid of both the current and previous frequency-domain CTFs for the sake of predicting the future CTFs. Furthermore, a sinc-interpolator is employed for the sake of deriving the frequency-domain CTFs associated with the data symbols. Our simulation results show that for a reasonable signal-to-noise ratio (SNR) value the proposed frequency-domain multiuser decorrelating based channel estimator is robust to the effects of both the MUI as well as the noise