Near-Field Modelling of the Leaky-Wave Antenna

The results of near-field simulation of leaky-wave antenna (LWA) intended for the Doppler meter of locomotive motion parameters relative to the underlying surface are presented. The simulation is performed along the longitudinal axis of the LWA radiating system which was presented as a set of elementary radiation sources with a uniform change in the phase distribution along its length. The resulting components of the E- and H-field strengths are found with the principle of superposition using a few assumptions about the relations between wavelength, radiation source length and radiation distance. The calculation results obtained in the MATLAB programming environment are presented in the form of two-dimensional charts of the amplitude and phase distribution of the E-field strength for the LWA Ka-band. Obtained results clearly shows a line-like periodical character of the LWA near-field which can be implemented as an advantage of short-range microwave radar sensors (SRMRS).