Novel Approach for Making Dynamic Range Measurements in Radio Frequency Front Ends for Software Controlled Radio Architectures

摘要

A novel setup to perform two-tone spurious-free dynamic range (SFDR) measurements on a mixer using a single analog input port is introduced. When access to the intermediate frequency (IF) port in a radio frequency (RF) front- end circuit is not available, the traditional two-port method for making an SFDR measurement is inadequate. Passing the analog input through a directional coupler between the RF combiner and the mixer facilitates the performance of the traditional third order intermodulation (IMD) test. Key differences between the single-port and traditional two-port setups are explained, and experimental data obtained using the single-port setup is compared to data obtained using the traditional two-port setup for two different mixer models. This data confirms that while the single-port approach yields similar results, a calibration to account for the additional losses introduced by the directional coupler is needed.