Traffic radar system
First Claim
1. Apparatus for installation on a movable platform structure and for determining the speed of a target structure while both structures are in motion, comprising:
- energy transmitting and receiving means for transmitting energy toward and receiving energy from reflecting surfaces for developing a first signal having components indicating the relative speed of said platform structure and said reflecting surfaces, platform structure speed measuring means operable independently of said energy transmitting and receiving means for developing a second signal corresponding to the speed of said platform structure relative to stationary objects, second speed measuring means including means for comparing said second signal and components of said first signal which are produced from reflections from a moving target structure for measuring the speed of the target relative to stationary objects, and calibration adjustment means associated with said platform structure speed measuring means for adjustment thereof to insure an accurate relationship between said second signal and the actual speed of movement of said platform structure relative to stationary objects.
3 Assignments
0 Petitions
Accused Products
Abstract
A traffic radar system is provided in which the speed of a target vehicle is determined by measuring the difference in frequency between a component of a doppler signal which has a frequency proportional to the relative speed of the target vehicle and a moving patrol vehicle and a reference signal having a frequency proportional to the speed of the patrol vehicle. The reference signal is developed from a tachometer device which generates a periodic signal having a frequency proportional to the rotational speed of a vehicle wheel and phase-locked loop arrangements including adjustable dividers are provided for locking an oscillator to the tachometer signal and generating a reference signal at a frequency proportional to the actual speed of the patrol vehicle. For calibration, a component of the doppler signal produced from reflections from stationary objects is used.
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Citations
12 Claims
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1. Apparatus for installation on a movable platform structure and for determining the speed of a target structure while both structures are in motion, comprising:
- energy transmitting and receiving means for transmitting energy toward and receiving energy from reflecting surfaces for developing a first signal having components indicating the relative speed of said platform structure and said reflecting surfaces, platform structure speed measuring means operable independently of said energy transmitting and receiving means for developing a second signal corresponding to the speed of said platform structure relative to stationary objects, second speed measuring means including means for comparing said second signal and components of said first signal which are produced from reflections from a moving target structure for measuring the speed of the target relative to stationary objects, and calibration adjustment means associated with said platform structure speed measuring means for adjustment thereof to insure an accurate relationship between said second signal and the actual speed of movement of said platform structure relative to stationary objects.
- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
Specification