Evaluation of Electric Field Inside Laboratory-Developed TEM Cell Using Vector Network Analyzer

This paper presents the development and performance of a prototype TEM cell designed at 950 MHz to establish the electric field measurement at the radio frequencies. A device with the dimensions 3 x 3 x 3 cm in size can be placed at the center below septum for testing of radiated emission or immunity. The parameters of this TEM cell have been measured on Vector network analyzer (VNA) over the operating frequency range. The measured insertion loss is found less than 1.5 dB and ports VSWR less than 2.0 in the desired frequency range. Generated electric fields with the uncertainty are evaluated at full and half septum height and presented over the measured frequency range. The uncertainty equation related to the measured S-parameters is presented and estimated considering the possible factors. Better homogeneity in the evaluated electric field distribution has been observed along the length of rectangular section at different frequencies. A standard electric field inside a shielded environment i.e. TEM cell has been generated, analyzed and its characterization over the radio frequencies have been presented.