A monolithic SiGe BiCMOS power amplifier for UHF RFID application

A monolithic power amplifier (PA) is designed and implemented for UHF RFID Reader. The presented PA is based on a 0.18 um SiGe BiCMOS process and its working frequency band is from 860 MHz to 960 MHz. It is a linear class AB type with two stages and all the biasing, the power and the matching circuits are on a single chip with the area of 1.1 mm × 0.9 mm. On-chip test results show that the small-signal gain S₂₁ is above 23 dB, the input return loss S₁₁ and the output return loss S₂₂ is less than -21 dB and -15 dB, respectively. Also the test result indicate the proposed PA has an output 1 dB compression point of 23.3 dBm, a PAE of 27% and a power gain of above 23 dB.