Abstract: As the core component of digital phased array radar, the stability and reliability of digital T/R module directly affect the performance of the whole system, and the state of local oscillator clock signal is the premise of stable operation of digital module. GaN power device and a new topology are adopted to redistribute the system gain, so as to achieve redundancy design. On the conditions of 4 dBm~6 dBm of frequency source output, the output power of 200 W is achieved for local oscillator amplification link (a single local oscillator amplifier is 50 W), and several thousands of channels of digital components are driven through array distribution network. Compared with the design of traditional local oscillator amplification chain, reliability of new amplification chain can be improved by one order of magnitude, thus improving the reliability of the radar system. Multi frequency transceiver function of the array can be realized, so that digital radar array has the ability of multi frequency transceiver. The abilities of anti-jamming, and the detection of near and far targets as well as the detection of undulating targets have been significantly improved, with practical significance to enrich the tactical functions of radar.