VLSI architectures and IC implementations for bandwidth-efficient communications.

摘要

This dissertation presents several novel approaches for implementing circuits that are basic components of digital communications systems. One fundamental contribution concerns a new architecture for the computation of the sine and cosine of an angle. It is based on an angle rotation algorithm and can be implemented by a multiplierless feedforward datapath, thereby allowing for easy pipelining and limited accumulation of roundoff errors. The modular architecture permits outputs of arbitrary precision by simply cascading enough angle rotation stages in the datapath. The angle rotation architecture is used to implement several basic communication system components including direct digital frequency synthesizers (DDFS) and digital quadrature mixers. For the DDFS the angle is generated by an overflowing accumulator. A prototype DDFS IC has been designed, fabricated in 1-