TABLE OF CONTENTS There has been an increasing interest in the problems and the techniques related to the so-called "blind channel identification and equalization" tasks in recent years. While channel identification and equalization have been studied extensively, their "blind" counterparts are relatively new.
A typical communication system consists of an information-bearing signal, a transmission channel, and the received signal. When the signal is known, then the system function of the channel can be identified by using the received signal. This is known as the problem of channel (system) identification. When the channel is known, then a channel equalizer can be designed in such a way that the complete system is an ideal delayer or the best estimator for the information-bearing signal. This process is known as the problem of channel equalization. Both problems of channel identification and channel equalization are well understood and well developed.
A typical communication system, however, is usually inherently blind, i.e., neither the information-bearing signal nor the channel is known. As such, the techniques of channel identification and channel equalization can not be immediately applied. The current technology relies heavily on so-called training sequences, which are...
