A Broad-Band Heated-Backlite Antenna for a Production Vehicle

The advantage of using the heater conductors of an automobile backlite as a broadcast receiving antenna, as compared to the use of a conventional telescopic whip, include reductions in damage, corrosion, aerodynamic drag and manufacurers’ costs. The paper develops an approach to the design of backlite antenna systems aimed at maximising the receiver signal input by attention to the form and position of the heater conductors and by minimising the deleterious effects of the feeder cable to the radio. Adequate levels of signal are shown to be available at lf, mf and vhf. To optimise performance, a buffer amplifier is used at lf and mf and the antenna is matched to a low-noise amplifier at vhf. Test results for sedan, hatchback and station wagon vehicles presented show very acceptable performance, in many cases better than those of conventional whip antennas.