National Key Laboratory of Solid-state Microwave Devices and Circuits，Nanjing Electronic Devices Institute
Abstract： In this paper, a novel optimization design scheme is proposed to solve the cascading mismatch problem of sub-circuits in beamforming chips due to parasitic effects. The optimization design scheme proposed in this paper is a design scheme that realizes impedance “pre-mismatch” by introducing the impedance traction effect of adjacent modules and offsetting it with the cascade impedance mismatch. The theory of the “pre-mismatch” technique is provided in the article and a 4-channel X/Ku-band RF transceiver chip has been fabricated to verify the feasibility and effectiveness of this scheme. Compared to conventional designs, the chip operates within the frequency band of 8 GHz~18 GHz, with the receive and transmit average link gains of 6.5 dB and 14 dB, respectively. Both transceiver link gains are increased by more than 2 dB. The transmit link output power is 21 dBm and power-added efficiency is 15.7%,，optimized by 1 dB and 9%. The receive link noise figure of 8.72 dB is reduced by 1.2 dB. The maximum phase-shifted root-means-square errors of the transceiver link are 5.25°and 5.12°, with a decrease of 1.75° and 3.17°.
