High Performance GaAs Microwave Monolithic Integrated Circuit Negative Resistance Voltage-Controlled Active Bandpass Filter
Tian Tong¹,Luo Jinsheng²,Wu Shunjun¹
(1. Xidian University, Xi'an 710071, China; 2. Xi'an Jiaotong University)

Abstract: An optimization design algorithm is presented for improving the performance of GaAs MMIC (microwave monolithic integrated circuit) negative resistance voltage-controlled active bandpass filter. Wideband amplifier is used in series with negative resistance voltageª²controlledactive bandpass filter. A pi type wideband matching circuit is employed at input terminal to ensure the wideband matching of the amplifier. The filter is structured by two nodes Butterworth filter with negative network in resonator. An experiment-verified planar varacter is also employed. A planar spiral inductor is adopted, together with a 0.8 micrometer MESFET parameter model in circuit simulation. The filter has an outstanding performance of 30 MHz passband width, about 400 MHz frequency tuning range, a 1.44~1.82 GHz operating band and a 10 dB average insertion gain.
Keywords: negative resistance;voltage-control;active filter;microwave monolithic integrated circuit