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This paper presents a novel adaptive predistortion technique for general cross-coupled microwave/RF filters with improved insertion loss and group-delay equalization. The method enables many potential applications of an almost abandoned technique, and permits a lower implementation technology to emulate the performance of a higher filter. 10-4-4 filters were built and tested at-and-band to verify the validity of the new method. The impact to satellite communication channels was also analyzed. Another novel concept of over-predistortion was proposed and evaluated and should lead to significant improvement for applications such as satellite transponder input multiplexers, where insertion loss can be traded off for in-band flatness, mass, volume, and even overall system performance.

The results of a prototype novel planar antenna providing dual-band performance for road-vehicle applications are reported. Multilayer stacked patches provide simultaneous RHCP polarization for GPS and vertically polarized low elevation coverage for 5.9 GHz DSRC operations. The results show good correlation between measurement and theory

Market growth in the area of thin route satellite communications services has led to consideration of non-traditional system architectures requiring sophisticated on-board processing functions. Surface acoustic wave (SAW) technology exists today which can provide implementation of key on-board processing subsystems by using multicarrier demodulators. This paper presents a review of this signal processing technology, along with a brief review of dispersive SAW device technology as applied to the implementation of multicarrier demodulators for on-board signal processing.

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