Title :
A microwave spread spectrum modem
Author :
Du Toit, Nicolaas D.
Author_Institution :
Kentron Pty. Ltd., Irene, South Africa
Abstract :
The design of a direct-sequence spread-spectrum modem intended for a mobile microwave communications link is described. Major design issues are signal generation and synchronization. The key features of this design are: (1) coherency among all frequencies: RF carrier, code clock, data bit rate, code repetition frequency and demodulator sample rate; (2) a combined carrier frequency and code phase-lock loop incorporating a single oscillator; and (3) software implementation of the automatic gain control loop filter, carrier frequency-code phase loop filter and an entire Costas loop
Keywords :
automatic gain control; microwave circuits; mobile radio systems; modems; spread spectrum communication; synchronisation; AGC; Costas loop; RF carrier; automatic gain control loop filter; carrier frequency-code phase loop filter; code clock; code phase-lock loop; code repetition frequency; combined carrier frequency; data bit rate; demodulator sample rate; design; direct-sequence spread-spectrum modem; frequency coherency; mobile microwave communications link; signal generation; single oscillator; synchronization; Bit rate; Clocks; Filters; Frequency synchronization; Microwave communication; Modems; Radio frequency; Signal design; Signal generators; Spread spectrum communication;
Conference_Titel :
Communications and Signal Processing, 1989. COMSIG 1989. Proceedings., Southern African Conference on
Conference_Location :
Stellenbosch
Print_ISBN :
0-87942-713-2
DOI :
10.1109/COMSIG.1989.129014
