Solid-state transmitters

The development of L-band solid-state transmitters at Raytheon is reviewed. A typical phased array transmit/receive module is described, and systems considerations are discussed in terms of higher-peak power operation. Since the advent of the interdigitized and the overlay geometries as methods for obtaining high power at microwave frequencies, the progress in the bipolar power field has far outstripped all expectations. While the design and optimization approaches for class-C amplifiers have greatly improved over the last few years, the selection of the proper matching circuitry still involves a complex interplay of many factors. It is shown that modules can be readily paralleled for additional power through the use of the low-loss sealed hybrid combiners now available. For large (phased array) transmitters it is not uncommon to have an availability factor greater than 0.999.