Antenna-in-Package and Transmit–Receive Switch for Single-Chip Radio Transceivers of Differential Architecture

A fully differential architecture from the antenna to the integrated circuit is proposed for radio transceivers in this paper. The physical implementation of the architecture into truly single-chip radio transceivers is described for the first time. Two key building blocks, the differential antenna and the differential transmit–receive (T–R) switch, were designed, fabricated, and tested. The differential antenna implemented in a package in low-temperature cofired-ceramic technology achieved impedance bandwidth of 2%, radiation efficiency of 84%, and gain of 3.2 dBi at 5.425 GHz in a size of 15×15×1.6mm³. The differential T–R switch in a standard complementary metal–oxide–semiconductor technology achieved 1.8-dB insertion loss, 15-dB isolation, and 15-dBm 1-dB power compression point (P_1\,dB) without using additional techniques to enhance the linearity at 5.425 GHz in a die area of 60×40μm².