Error analysis of angle measurement for two-dipoles antenna measurement system

In order to increase the coherent accumulation time to improve signal-to-noise ratio (SNR), a novel four-element antenna system of direction finding is presented to solve the problem of low direction finding (DF) accuracy in miniature meter wave radar. This method adopts virtual polarization technique to obtain virtual polarization receiving of right-hand circularly polarized (RHCP) and left-hand circularly polarized (LHCP) signals. It can realize omnibearing angle measurement. Mathematical models of signal are established by means of quantitative analysis of five major factors, which can affect DF accuracy. Formulas of error are derived for angle measurement. Experimental data results indicate that it can achieve good performance for angle measurement, if five influencing factors are quantified and controlled in limited range.