A direct Quadrature Modulator for 0.9 To 2.5 GHz wireless systems


As wireless system designs have moved from carrier frequencies at approximately 900MHz to wider band-width applications like Personal Communication System (PCS) phones at 1.8GHz and wireless local area networks at 2.4GHz, you have been forced to implement discrete RF designs because of the absence of RF integrated circuits (RFICs) at these higher frequencies. System designs at these higher frequencies have a great need for highly integrated RFICs for quadrature modulators, power amplifiers, and low noise amplifiers/mixers.