Direct conversion EHM transceivers design for millimeter-wave wireless applications

A direct conversion modulator-demodulator 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 modulator-demodulator. The transmission of 16-QAM signal with 110 Mbps data rate over fixed wireless link has been examined. We also evaluate the different levels of I/Q imbalances and DC offsets 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. Copyright (c) 2007 Abbas Mohammadi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.