A direct conversion modulatordemodulator with even harmonic mixers for fixed wireless applications is presented. The circuits consist of even harmonic mixers (EHMs) realized with antiparallel diode pairs (APDPs). A communication link is set up to examine the overall performance of proposed modulatordemodulator. The transmission of 16-QAM signal with 56Mbps data rate over fixed wireless link has been examined. We also evaluate the different levels of I/Q imbalances and use signal space concepts to analyze the bit error rate(BER) of the proposed transceiver using M-ary QAM schemes. The results show that this structure can be efficiently used for fixed wireless applications in Ka-Band
