In this work, using InGaP/GaAs HBT, we have developed highly integrated Ku-band downconverter including LO rejection filter, mixer and two stage amplifiers. Especially, spiral inductor was optimally designed for a rejection of LO leakage and second harmonic LO leakage signal.
According to measurement results, the downconverter MMIC showed a conversion gain of 9.5 dB and IIP3(Third order input intercept point) of -4.5 dBm. The downconverter MMIC showed a LO leakage suppress of -36 dBc and second harmonic LO leakage suppress of -55 dBc, respectively. The good LO and its second harmonic suppress characteristic was resulted from the optinally designed spiral inductors.
Above results indicate that Ku-band downconverter employing InGaP/GaAs HBT exhibited good RF performances, and the proposed Ku-band downconverter employing InGaP/GaAs HBT is a promising candidate for a realization of one chip transceiver.