Jacob Benesty Yiteng ( Arden ) Huang Adaptive Signal Processing : Application to Real - World Problems

Since the introduction of adaptive equalizers in digital communication systems by Lucky [1], much progress has been made. Due to their particular constraints many new and different concepts in the wireless domain have been proposed. The wireless channel is typically time and frequency dispersive, making it difficult to use standard equalizer techniques. Also, due to its time varying nature, long transmission bursts may get corrupted and require a continuous tracking operation. Thus, transmission is often performed in short bursts, allowing only a limited amount of training data. Furthermore, quite recently, advantages of the multipleinput multiple-output character of wireless channels have been recognized. This chapter presents an overview of equalization techniques in use and emphasizes the particularities of wireless applications.