1引言20世纪末文明的进步极大地依赖于以半导体材料为基础的电子技术的迅速发展；然而，当今技术的直接推广已不能应付人类在下个世纪必须面对的纷繁复杂的社会和环境的挑战。随着信息密集型社会的来临，需要建立一个全新的技术基础。电信号处理在时域上是连续的（seuen－tial 1 INTRODUCTION The progress of civilization at the end of the 20th century relied heavily on the rapid development of electronic materials based on semiconductor materials. However, the direct promotion of today’s technology has failed to meet the complex social and environmental challenges humans must face in the next century. With the advent of information-intensive society, a completely new technological foundation needs to be established. Electrical signal processing is continuous in the time domain (seuen-tial