SAW device provides hyperbolic chirp
Abstract
The 'echo' location system employed by bats utilizes pulses whose frequency varies with time. This system is hyperbolically, rather than linearly weighted. It is pointed out that this concept of hyperbolic weighting, implemented with relatively inexpensive surface accoustic wave (SAW) devices, can be applied to torpedo guidance and satellite interception. The use of hyperbolic weighting allows the use of chirp by reducing the nonlinearity of the Doppler shift. The use of a hyperbolically weighted chirp (HWC) provides an approach for substantially overcoming a problem caused by the Doppler effect. The block diagram of a typical spread spectrum detection, tracking, and homing system is presented. This system uses a nonlinearly weighted SAW device as a spectrum spreader and compressor.
- Publication:
-
Microwaves
- Pub Date:
- November 1983
- Bibcode:
- 1983MicWa..22..108J
- Keywords:
-
- Chirp Signals;
- Hyperbolic Functions;
- Pulse Compression;
- Satellite Guidance;
- Surface Acoustic Wave Devices;
- Doppler Effect;
- Matched Filters;
- Spread Spectrum Transmission;
- Weighting Functions;
- Electronics and Electrical Engineering