Complexity, cost, power dissipation, and the number of required external components have been the primary criteria in selecting the complex receiver architectures for today’s digital communications market. Of the many alternatives, the homodyne receiver architecture, also called direct conversion and zero-IF, has emerged as the architecture of choice to best meet these requirements. But this receiver approach also comes with some design challenges that must be considered. DC offset, I/Q mismatch, and even-order distortion are aspects of direct conversion architecture performance that effect the receiver’s EVM performance and must be managed properly.

This webcast provides an overview of heterodyne and homodyne architectures, with a detailed look at the direct conversion approach. The sources and effects of I/Q offset and mismatch, and other anomalies are analyzed and discussed, and a circuit solution, quadrature error correction, is introduced along with a performance improvement analysis. Actual Analog Devices direct conversion receiver components are used for the performance comparison results.

Qui Luu joined Analog Devices in 2000 as a Product Engineer and then later an applications engineer in the High Speed Converter Group. She received her BSEE from Worcester Polytechnic Institute and MSEE from Northeastern University.