Application of GaN high power chips in T/R modules

Digital transmit/receive modules (digital T/R modules) play a vital role in active phased array antennas for electronic warfare applications. High power amplifier (HPA) chain is the key component in the next generation of T/R modules for the future S band phased array antenna. Today GaAs MMIC HPA is widely used in most of T/R modules. However, the drawbacks of GaAs MMIC HPA such as low efficiency and limited output power level (usually in the range of 5W to 15W) have made it not to be a competent candidate of power chips. In this paper, the GaN power chip with better characteristics is introduced and analyzed. Compared with GaAs MMIC HPA, it has remarkable advantages such as high power, high-gain, high efficiency, wide operating bandwidth, and etc. An S band 85W GaN power chips amplifier is developed and investigated. The performance tests of the amplifier have verified that the performance of T/R modules can be improved by using the GaN power chips. The improvements of the T/R modules system in output power, efficiency, reliability, size and weight have illustrated that the GaN power chips is a prime candidate for warfare systems and electronic warfare application.