DESIGN METHODOLOGY AND EXPERIMENTAL RESULTS FOR NEW LADDER-TYPE SAW RESONATOR COUPLED FILTERS

Design methodology and experimental results for a new type of SAW filt er called an ''extended SAW resonator coupled filter'' used in 800 MHz and 0.6 to 1.0 watt cellular radios are presented, The new filters ha ve very small nonlinearities as well as high-performance and high-powe r characteristics. We have proposed a new equivalent circuit model for IDTs with leaky SAWs, which includes the propagation losses due to le akage and conductances caused by bulkwave radiation, Synthesis procedu res for the new SAW filters based on the new treatments of leaky SAWs are discussed, and simulation and experimental results are also given, The new filters satisfy not only the required frequency-response spec ifications but also the spurious response sensitivity for an antenna d uplexer used in USA cellular radio.