| 摘要 |
<p>Doppler radar apparatus for use in a velocity measuring system for farm tractors and the like. The apparatus includes a dual mode conical horn having a flare angle substantially in excess of 12.5.degree., and a dielectric lens formed of a glass filled polymer. The doppler output signal provided by the RF transceiver associated with the dual mode horn is high pass filtered to remove low frequency signals therefrom. The horn is mounted in such a way that it is isolated from mechanical vibrations which would induce doppler signal frequencies in excess of the cutoff frequency of the high pass filter. Moreover, the horn assembly (which is aluminum) and a steel housing assembly are coupled together in such a way that thermal expansion and contraction will not loosen the friction fit between the two assemblies. The two assemblies are held together by a single, large diameter annular locking ring.</p> |
