Models from Identification
This chapter describes the process of deriving the velocity loop model from field test data. It includes the description of the white noise testing of an antenna, test conditions, input and output signals, open- and closed-loop testing, the instrumentation set-up, and the system identification test. Analytical background for the data description and data processing are also included. Next, the dependency of the antenna model on its elevation position, and on the dish diameter is discussed. Finally, analytical and identified models are compared.
White Noise Testing of the Antenna
The white noise signal is applied at the input of the velocity loop to excite the antenna dynamic, and the antenna reaction is measured at the encoder. The white noise is a random signal of even spectrum within the antenna bandwidth; hence each frequency component of the antenna dynamics is excited evenly. It should guarantee to obtain a meaningful transfer function and trustworthy model of the velocity loop.
KeywordsTransfer Function Power Spectral Density Function Elevation Position Loop Transfer Function Position Loop
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