Update on constant-current solid state modulator

The constant-current solid-state modulator in the AN/SPY-1 radar transmitter is described. Modifications required to improve the efficiency and operation of the original design are described. Added protection to the modulator was required, and several changes were made to improve its reliability, simplicity, and cost. The MTI (moving target indicator) performance of the solid-state modulator (SSM) versus the switch-tube modulator (STM) is evaluated in regard to intrapulse noise and clutter attenuation. Future work is outlined which is expected to result in a highly reliable fleet-operated system that will provide a fast response to anti shipping threats from aircraft and missiles.<>