Modified H-shaped antenna for automotive digital terrestrial reception

A modified H-shaped antenna is proposed for automotive digital terrestrial reception. The antenna is analyzed by the method of moments. The antenna has the feature that a figure-8 radiation pattern is rotated with increasing frequency. Four symmetrically mounted antennas at the top of the front and rear windows of a car have gain to the sides of the car as well as to the front and rear directions. The VSWR is less than 3 from 470 to 710 MHz since the antenna has three resonant modes. Measurement results for a single prototype antenna agree with the calculation results. The reception system adopts an adaptive array based on the maximal ratio combining (MRC) method. A near omnidirectional pattern was obtained in a plotted pattern of steered beam in the horizontal plane with the mounted prototype antennas.