Frequency-hopped waveform synthesis by using s.a.w. chirp filters

The design and construction of a surface-acoustic-wave (s.a.w.) pseudonoise (p.n.) code controlled frequency-hopping (f.h.) synthesiser for spread-spectrum (s.s.) communication is reported. The prototype synthesiser uses s.a.w. chirp filters with 60 MHz centre frequency, 5 MHz/¿s is dispersive slope and 25 MHz bandwidth, and operates in both continuous-wave and f.h. modes. Experimental results show an output centred on 120 MHz, electronically programmable over a 25 MHz bandwidth in 63 discrete hops.