A 6–20 GHz 400-MHz Modulation-Bandwidth CMOS Transmitter IC

Abstract

This paper presents a transmitter IC with two identical signal paths, including base-band amplifier, up-converting mixer, and power amplifier (PA) stages. The design is focused on wide modulation bandwidth, and the use of a resonatorless small die-area class-D power amplifier at cm-wave frequencies. This work also incorporates a local oscillator (LO) signal distribution network with phase tuning elements. The circuit is implemented in a 22-nm CMOS process, and the active die area is 0.8 mm2. Operation over the 6–20 GHz range of carrier frequencies through the transmission of both continuous wave (CW) and wideband quadrature phase shift keying (QPSK) modulated signals were verified with measurements. Results with 20/40/100, and 400 MHz modulation bandwidths are presented, and for instance for a 20-MHz QPSK modulated input signal the measured adjacent channel leakage ratio (ACLR) of the transmitter is 28 dBc and error vector magnitude (EVM) is 5%.