A Compact W-Band Frequency Tripler Using Single-Balanced Topology

This letter presents a compact W-band frequency tripler implemented in a 0.13-μm SiGe BiCMOS technology. It uses a single-balanced differential pair core overdriven as Class A amplifiers. The usage of a single-stage multiplication without any additional amplifying stage along with the on-chip transformer baluns for single-ended to differential conversions at the input and the output improves efficiency, at the same time enabling a compact design. The third-order harmonic is further improved by enhancing the second-order harmonic at the common node of the differential pair, which in turn mixes with the input and contributes to the third-order harmonic. The tripler generates a saturated output power of 2.9 dBm at 84 GHz with fractional 3-dB bandwidth of 25.6%, ranging from 75 to 96 GHz and an in-band fourth-harmonic suppression of more than 20 dBc. The chip occupies an area of 435 μm × 560 μm (0.24 mm2) and consumes 88 mW from a 3.3-V power supply.