Title :
Specification and development of an equalizer-demodulator for wideband digital microwave radio signals
Author :
Wolff, Vincent ; Gooch, Richard ; Triechler, J.
Author_Institution :
Appl. Signal Technol. Inc., Sunnyvale, CA, USA
Abstract :
The authors describe the specification and implementation of a sophisticated digital signal processor to be used for equalizing and demodulating high-rate, high-order quadrature-amplitude-modulated (QAM) signals used in digital radio systems. The processor uses state-of-the-art algorithms as well as the latest high-speed CMOS VLSI technology to achieve a processing rate in excess of 10 gigamultiply/adds per second. The system exhibits several unique features; in particular, 40 Mband signals can be processed with 64-tap equalizer and the functions of baud and carrier recovery are implemented digitally. The signal processing problems to be solved are described, and from them a set of requirements is developed. A summary of the algorithms needed to recover symbol timing, equalize the incoming signals, and remove carrier offset is provided. A brief discussion of the hardware tradeoffs is followed by a detailed description of the system design
Keywords :
CMOS integrated circuits; VLSI; amplitude modulation; broadband networks; demodulators; digital radio systems; equalisers; microwave links; QAM; carrier offset; equalizer-demodulator; high-speed CMOS VLSI technology; symbol timing; wideband digital microwave radio signals; CMOS process; CMOS technology; Digital communication; Digital signal processors; Equalizers; Quadrature amplitude modulation; Signal processing; Signal processing algorithms; Timing; Very large scale integration;
Conference_Titel :
Military Communications Conference, 1988. MILCOM 88, Conference record. 21st Century Military Communications - What's Possible? 1988 IEEE
Conference_Location :
San Diego, CA
DOI :
10.1109/MILCOM.1988.13432
