Simulation studies of errors in HF radar ocean surface current measurements

Simulation techniques are applied to evaluate the performance of HF radar surface current algorithms. The simulation assumes that the ocean echo is due to first order Bragg scatter from a large number of differential area elements in an annular ring of the ocean surface, and generates, to first order, the voltage time series data which would be sampled from an eight element phased array, at four frequencies from 4.8 to 21.8 MHz. The geometry and frequencies match those of a pair of existing pulsed radar systems currently deployed at Monterey Bay. The simulation addresses the problem of estimation of accuracy and error bounds for the ocean radar system. The authors examine physically plausible surface current profiles with random fluctuations in the amplitude of the scattered signal as a function of position on the ocean surface. Deviations between simulation input and algorithm output as a function of the parameters input to the simulation are examined for both direction finding and beam forming algorithms.