Synthetic DSP approach for novel FPGA-based measurement of error vector magnitude

Abstract

A new implementation of EVM measurement has been developed in a production test environment using an FPGA-based DSP processor within an ATE test solution. The focus of interest is in identifying key areas of the DSP that affect measurement quality and optimizing their execution on an FPGA to increase measurement accuracy, precision, repeatability, and reduce test time. This approach defines a real-time processing methodology for signal demodulation and EVM calculation as opposed to traditional PC-based post processing and offline computation of EVM. The analysis of the DSP elements and their corresponding error artifacts are presented in a standard approach to EVM measurement. The experimental results of the digital demodulation system and EVM measurement in MATLAB/Simulink are compared against a bench-top Rohde&Schwarz complex signal generator and vector signal analyzer to qualify the results.