Title :
Compact Fast-Hopping Frequency Synthesizer for Spread-Spectrum Systems
Author :
Budreau, Alan J.
Author_Institution :
Electromagnetic Sciences Division, Rome Air Development Center, Hanscom AFB, MA 01731; EEA, RADC Electromagnetic Sciences Division, Hanscom Air Force Base, MA 01731.
Abstract :
This paper describes a compact synthesizer developed* for an Air Force spread-spectrum system. The prototype from TRW (ref. 1) covers the 1280-1535 MHz range in integral MHz steps, with a hopping speed of approximately 25 nanoseconds. As all the output frequencies are obtained by multiple mixing of only two clock-referenced input tones, the long-term stability of the output is as good as that of the clock. The overall architecture is that of an iterative synthesizer, with four identical stages of divide-and-mix. A 1Ã4 switch at each stage chooses the additional tone to be mixed in. Use of four identical modules facilitates the use of custom RF LSI chips, leading to the achievement of small size and low cost.
Keywords :
Clocks; Costs; Frequency conversion; Frequency synthesizers; Large scale integration; Radio frequency; Spread spectrum communication; Surface acoustic waves; Switches; Voltage-controlled oscillators;
Conference_Titel :
Military Communications Conference - Progress in Spread Spectrum Communications, 1982. MILCOM 1982. IEEE
DOI :
10.1109/MILCOM.1982.4805911