Low-cost handheld multiprobe reflectometer for the ISM band

In this paper we present a design procedure and a working model of low-cost handheld complex reflection coefficient tester for the ISM band. The tester is based on the concept of mutliprobe reflectometer and uses the integrated Analog Devices AD8318 power detectors. Measurements are controlled by the Atmel ATMega32 microcontroller. A prototype tester with friendly user interface was designed and realized for 2.3 – 2.6 GHz range, covering the lower WiFi band. Results of numerical simulations and experimental tests are presented.