Tiny Integrated Network Analyzer for Noninvasive Measurements of Electrically Small Antennas

Abstract

Abstract-Antenna mismatch and crosstalk are recurring issues in telecommunications. For electrically small antenna systems these are very hard to measure without affecting the radiation performance of the system and, consequently, the measurement itself. Electrically small antennas are found in many applications ranging from consumer electronics to industrial systems. We propose a radically new approach to characterize crosstalk and mismatch based on vector network analysis. By miniaturizing the network analyzer it can be integrated in the system under test eliminating the need for cables leaving the system. The tiny integrated network analyzer (TINA) is a standalone Arduino based measurement system utilizing the transmit signal of the system under test as its reference. It features a power meter with triggering ability, on-board memory, USB and easy extendibility with general purpose I/O. The accuracy and repeatability of the proposed system is documented through the repeatability of the calibration. To showcase the capabilities of the system, a measurement is done on a modified smart phone with the system inside. These early results show great promise for miniaturized network analysis. With the advances in software defined radio we can expect much more flexible and advanced integrated network analyzers in the coming years.

Electrically small naturally circularly polarised antenna

“…In contrast, to measure the input impedance and radiation pattern, one needs to connect the ESA to a network analyser through a cable, which makes the entire system much larger than the original device. Therefore, the directly measured quantities do not necessarily represent the input impedance and radiation pattern of the standalone ESA [17][18][19][20].…”