Abstract: A plurality of antennas attached to the glass of the rear window of a vehicle produces patterns that may be combined to give directional pick up patterns. The first basic antenna is two spaced vertical whip antennas connected by parallel horizontal delay lines. Each whip output has a cardioid pick up pattern in the direction of the other antenna, in this case to the right and left. The second antenna is connected vertically across the window opening. Its output has a figure eight pick up pattern, typical of a slot antenna, with the lobes to the front and rear of the vehicle. The phase relationship of these three pick up patterns are such that if properly combined, then either of two sets of pick up patterns can be obtained. The first pattern is the basic right and left cardioid, and the second pattern is the front and rear cardioids. When used in combination with a communications receiver and processor, the direction of the transmitter can be determined, regardless of which quadrant it lies.
Type:
Grant
Filed:
June 2, 1977
Date of Patent:
May 23, 1978
Assignee:
Field Operations Bureau of the Federal Communications Commission