Analysis and Design of Ultra-Wideband mm-Wave Injection-Locked Frequency Multiplier Based on Complementary-Phase Cascade-Parallel Resonator

A complementary-phase resonator (CPR) consisting of two parallel sub-networks based on complementary-phase concept is presented, whose phase frequency responses are designed to counteract each other so as to obtain an ultra-wide continuous phase plateau with small ripples and an injection current boosting (ICB) characteristic, allowing significant extension of the locking range (LR) for the millimeter-wave (mm-wave) injection-locked frequency multipliers (ILFMs). Subsequently, the widely used output buffer (cascaded with the ILFM core and incorporating a transformer as its load) is merged into the CPR to form a complementary-phase cascade-parallel resonator (CP²R), which poses a cascaded signal transmission path and a parallel complementary structure similar to the CPR, inheriting the advantages of complementary phases and facilitating an increased resonator impedance magnitude and a compact chip area. The proof-of-concept design of an injection-locked frequency doubler relying on the CP²R is fabricated in a 40-nm CMOS process. It achieves a LR of 41.7% from 72 to 110 GHz under 0-dBm injection power, covering the entire W-band without resonator tuning or multi ratio mode switching. As the injection power is reduced to −3 dBm, the LR of the CP²R-ILFM remains competitive, spanning from 78 to 106 GHz. The measured output power is above −12 dBm from 80 to 102 GHz with a maximal output power of −6.2 dBm at 88 GHz. The chip occupies a core area of 0.039 mm² and dissipates 9.4 mW from a 0.9-V voltage supply.