Vibration Measurement and Analysis of Mechanical Design of the Antenna Radar System

The aim of this paper is to purpose a methodical algorithm how to measure and analyze complex vibration patterns of an antenna gearbox. The main problem is to analyze the health of a gearbox without knowing the exact state of the gearings inside. In many cases it is not possible to an exact number of gearings and number of teeth on each gearing. The technique to obtain the health condition of the whole gearbox is to take a complete picture of vibration measured with a gearbox in good condition, and then compare it to vibrations of an aged gearbox, based on cepstral analysis. Measurements were made from very low frequencies 1Hz up to 12.5 kHz. The Analog to Digital Converter (ADC) used for this application has a resolution of 24 bits with a 25 kHz sampling rate. The digital signal is windowed by a Hann function and then the CEPSTRUM is calculated. Because of the impossibility of measuring of a worn gearbox, this study only shows the results measured on the new gearbox. The methodology how to measure and analyze internal vibrations of a gearbox is shown in this study and what results can be expected from those measurements.