A 44-GHz high IP3 InP-HBT amplifier with practical current reuse biasing

This paper will discuss the practical design of an InP-based heterojunction bipolar transistor (HBT) Q-band high IP3 monolithic microwave integrated c ircuit (MMIC) amplifier. The amplifier features a novel "double-balanced" d esign approach that incorporates a practical "current reuse" biasing scheme , The current reuse biasing results in a 40% reduction in current consumpti on through a standard 5-V supply and simplifies the MMIC's system integrati on while the double-balanced design produces wide-band IP3, gain, and excel lent out-of-band return-loss performance required for practical application s, The three-stage MMIC amplifier achieves 15.4 dB of gain, 28.3 dBm of IP3 , and a P-sat of 16.2 dBm at 44 GHz, An output-stage IP3/P-dc ratio lineari ty-figure-of-merit of 5.3 is obtained and is believed to be among the best reported for an InP-HBT amplifier operating at Q-band frequencies. The IP3 performance was optimized using load-pull simulations based on a custom HBT IP3 model. Different device cell configurations such as the common-emitter , common-base, and cascode were also considered, The common-emitter amplifi er results of this paper demonstrate the promising linearity performance of InP-HBT's and its practical bias and integration capability which is attra ctive for Q-band receiver applications.