Abstract: A base band transmitter cooperates with dual base band receiver antennas, a single receiver channel, and a tapped delay correlator device for the prevention of vehicular collisions, the configuration effectively narrowing the normally wide base band antenna pattern to span a single predetermined forward traffic lane.

Abstract: The operating characteristics of deep well pumping equipment in a geothermal well power-generation system are observed by cooperating sensor and communication elements permanently associated with the geothermal well equipment itself. Bridge circuit sensors detect well water temperature and water pressure below and above the pump, while a further sensor detects pump rotational speed. The data is transmitted by a multiplexing acoustic communication link coupled to receiver and display means located at the earth's surface. An electrical generator driven at the pump speed serves as the rotational speed pick off and additionally supplies multiplexing and signal processor power for use at the down-well site.

Abstract: A method and apparatus for measuring the level and dielectric constant of a liquid which includes a device for generating a subnanosecond baseband pulse that propagates through a transition device to a single wire transmission line that extends through an air filled region into the liquid. A discontinuity created at the air liquid interface produces a reflection of the baseband pulse that is compared with the transmitted pulse with respect to time of arrival and amplitude to determine the liquid level and the reflection coefficient at the air liquid interface. The reflection coefficient is then utilized to determine the dielectric constant of the liquid.

Abstract: A range measurement system wherein range accuracies of fractions of a meter may be obtained. Nanosecond pulses, one triggered by the transmitter trigger with an appropriate delay and the other triggered by a received echo pulse, are launched from opposite ends of a transmission line. The location on the transmission line at which the two short pulses coalesce and the delay time of the transmitter triggered short pulse establish the range to the echoing object to an accuracy determined by the short pulse, pulse width.

Abstract: A pulse transmitter-receiver system for detecting the presence and proximity of objects employs transmission of short base-band or subnanosecond electromagnetic signals and reception thereof by a dispersionless, broad band transmission line antenna system with a receiver circuit cooperating with a biased semiconductor diode located within the transmission line antenna system for instantaneously detecting substantially the total energy of each reflected base-band pulse and for providing corresponding outputs suitable for indication of the presence or of the range of such proximate objects.

Abstract: A vehicle safety apparatus includes a base band pulse transmitter-receiver system for the detection of an impending collision immediately prior to the contact of the vehicle with another object for the actuation of restraining or other safety devices to protect the occupants of the vehicle when the crash event actually occurs. A semiconductor base band transmitter and receiver system is synchronously operated by a master clock, providing precise operation of the receiver gain control, sensitivity time control, and other receiver functions, in a low-cost, rugged, long-lived object detection system.