Transmit pulse shaping filters and CORDIC algorithm based precompensation for digital satellite communications

The design and architectural implementation of low complexity pulse shaping filters and algorithmic precompensation for satellite communications transmitters is presented. A lookup table (LUT) approach is used to implement the pulse shaping that provides good spectral efficiency with low implementation loss. A COordinate Rotation Digital Computer (CORDIC) algorithm technique is use to implement the precompensation, resulting in a reduction of the deleterious effects of channel nonlinearities. An architecture for adaptive precompensation is also presented. Issues including number representation, BER performance, and Programmable Logic Devices (PLDs) complexity are discussed. Emphasis is placed on low complexity techniques to enable throughput rates in the tens of megabits per second using today's PLDs.