Modeling, Failure Diagnosis and Troubleshooting of UHF Radar Transmitter

This paper presents failure diagnosis of UHF radar transmitter that generates less RF power compared to the designed value. To determine the failed modules, complete measurements are done for the dividers and combiners using vector network analyzer also all power amplifiers are measured using spectrum analyzer, Measurements results show that dividers and combiners have a big loss and they should be redesigned. Redesign is done using ADS software, also a complete modeling is done for the transmitter using AWR microwave office. Modelling of the transmitter is done using the measured s-parameters of the failed dividers/combiners and it is done once again after the redesign of the dividers/combiners that shows a good output power of the transmitter (69.6 dBm) with a flat gain (19.7 dB) and good matching (almost better than -20 dB), which is enhanced too match compared to the one of the original TX.