Table of Contents
Advances in Electrical Engineering
Volume 2016, Article ID 8039679, 17 pages
http://dx.doi.org/10.1155/2016/8039679
Research Article

Comparison of 6 Diode and 6 Transistor Mixers Based on Analysis and Measurement

1Ericsson Telecom Hungary Ltd., Irinyi József Utca 4-20, Budapest 1117, Hungary
2Department of Broadband Infocommunications and Electromagnetic Theory, Budapest University of Technology and Economics, Egry József Utca 18, Budapest 1111, Hungary

Received 7 March 2016; Accepted 6 April 2016

Academic Editor: Mamun B. Ibne Reaz

Copyright © 2016 J. Ladvánszky and K. M. Osbáth. 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.

Abstract

Our goal is to overview semiconductor mixers designed for good large signal performance. Twelve different mixers were compared utilizing pn diodes, bipolar transistors, and/or junction field effect transistors. The main aspect of comparison is the third-order intercept point (IP3), and both circuit analysis and measurement results have been considered. IP3 has been analyzed by the program AWR (NI AWR Design Environment) and measured by two-tone test (Keysight Technologies). We provide three ways of improvement of large signal performance: application of a diplexer at the RF port, reduction of DC currents, and exploiting a region of RF input power with infinite IP3. In addition to that, our contributions are several modifications of existing mixers and a new mixer circuit (as illustrated in the figures). It is widely believed that the slope of the third-order intermodulation product versus input power is always greater than that of the first-order product. However, measurement and analysis revealed (as illustrated in the figures) that the two lines may be parallel over a broad range of input power, thus resulting in infinite IP3. Mixer knowledge may be useful for a wide range of readers because almost every radio contains at least one mixer.