Showing papers on "Collision avoidance system published in 1973"

Harmonic radar helps autos avoid collisions

Abstract: In the foreseeable future, a radar system immune to clutter through use of a special reflecting tag could aid the the driver to maintain a safe distance between the cars, the closing rate, and the driver's ground speed. To eliminate the clutter and blinding problems, a system has been designed that uses an harmonic radar concept. An experimental harmonic radar collision avoidance system has been built using an RCA transferred electron oscillator power source. The measurement of distance was quite repeatable and of adequate accuracy for highway use. In the automatic braking system once the alarm is given, the brake pedal is automatically depressed by a force that increases linearly with time up to maximum pressure until the alarm is removed. The force is then removed linearly with time. The harmonic radar system will reject all blinding signals that it receives other than the second harmonic of its transmitted frequency. The possibility of a false alarm from crosstalk interference is reduced with harmonic radar. The system is adaptable to integrated and printed-circuit techniques. It operates in regions of the frequency spectrum which are still underutilized and spectrum space can be set aside for its future use. The average power density in the immediate vicinity of the antenna is 0.2 mW/cm2. When a dangerous driving situation is detected, an audible warning is sounded and a warning light is flashed. The harmonic radar system provides protection from certain types of rear-end collisions; those where the car in front is in line with the following car. Vehicles that are stopped, but not parallel to the center line, will not be "seen" by the following car because of the purposefully narrow beam of the passive reflector./SRIS/

Air traffic control collision avoidance system interface simulation, phase ii

Abstract: : A second phase of dynamic simulation is reported to further investigate the nature and extent of interaction between the air traffic control (ATC) system and an airborne collision avoidance system (CAS). Objectives were to investigate the impact on ATC when the preemptive CAS diverted an equipped aircraft into an encounter with an unequipped aircraft, to investigate the effectiveness of a strategy for switching the CAS threat detection from full system mode to landing mode, and to explore the three-way interface between a proposed general aviation version of the CAS, the commercial CAS and ATC system. The environment was a high-density terminal area which provided for simultaneous approaches to parallel runways.

Realization of a horizontal collision avoidance system

Abstract: For a two-aircraft encounter, the computer realization of a cooperative horizontal collision avoidance system is analyzed. The system is based on range, relative bearing, relative heading and speed ratio information, and the realization accounts for the turn dynamics of both aircraft.

Aircraft collision avoidance system by passing means

Abstract: A passive collision avoidance system, having particular applicability to aircraft collision avoidance, comprising two receivers operating out of antennas which have a differing sensitivity to the polarization of the incoming signals from a ground broadcast facility. The differing sensitivity ensures that the direct and reflected signals will predominate in different receivers and therefore when the outputs of the receivers are combined the resultant fade rate will give an indication of the movement of the intruding aircraft with respect to the equipped aircraft. Interpretation of the fade rate allows the equipped aircraft to change course until a non-collision course is attained.