A new saw device substrate for synthetic aperture radar

This paper presents an outline of a coherent pulse compression-expansion sy stem constructed for an airborne synthetic aperture radar (SAR). The design concept, system performance, and experimental results are presented. Notab ly, a pair of conjugate surface acoustic wave (SAW) dispersive delay lines is implemented on a Bi12GeO20 substrate for the first time. The Bi12GeO20 s ubstrate is chosen as a good tradeoff between insertion loss and temperatur e stability. Furthermore, its low acoustic velocity provides the added adva ntage of being able to use a shorter line to achieve the same time delay. ( C) 2000 John Wiley & Sons, Inc.