Review of channel estimation for wireless communication systems

Wireless communication systems have evolved over the ages. However, there are some undesirable effects of a wireless communication channel on the signals transmitted through it which are caused by the physical properties of the channel. These in turn always result in attenuation, distortion, delays, and phase shift of the signals arriving at the receiver end of the communication system. Consequently, there is a need to provide perfect and up-to-date estimate of the channel, in order to compensate for these effects, and for accurate signal demodulation, equalization, decoding, and a host of other baseband processing applications at the receiver end of the systems. In this article, a review of the various channel estimation techniques is provided. This review will be of assistance in reaching a compromised decision regarding channel -estimation techniques to be employed in any wireless communication systems being developed.