Abstract
This paper provides a measuremnet model for Linear FM(LFM) chirp waveforms in Cartesian coordinate. The model is derived by first incorporating the Doppler shift term into the measurement model in radar coordinate, and then transform it to Cartesian coordinate. The proposed model is then applied to a simple airplane tracking problem. The simulation result shows better tracking performance than the case with ordinary measurement model. It is also shown that up chirp radars has better tracking performance than down chirp radars.