Single Balanced Mixer for UWB Applications

This paper presents the design and performance of a planar single balanced broadband mixer. A wideband balun is used to feed the balanced LO input to the mixer circuit. This design is fabricated on 8mil Roger's RO4003C substrate and commercially available Aeroflex/Metelics MGS-904 GaAs beam lead schottky diodes are used to provide non-linearity for the mixing. This mixer requires no external bias and can operate for a frequency range (RF/LO) from 3GHz to 18GHz. Measured performance shows an average conversion loss of 15dB along with LO-IF isolation better than 24dB. The mixer can be used for designing cost effective components for variety of UBW applications such as Wi-Fi, WiMAX, GSM etc.