Highly Linear 1.765 GHz Downconversion Double Balanced Mixer using InGaP/GaAs HBT Technology for AF-ICS Application

In this paper, an enhanced linearity down-conversion double balanced mixer (DBM) is implemented using InGaP/GaAs HBT technology for adaptive feedback-interference cancellation system (AF-ICS). This circuit is composed of internal bias supply, common collector output buffer for impedance reduction, and degeneration capacitor to improve linearity within a total area of 875times775 mum². The results show that the degeneration technique improves linearity and achieves a conversion gain of 3.1 dB, a third-order input intercept point (IIP3) of 12.77 dBm, a third-order output intercept point (OIP3) of 15.87 dBm.