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Ehrlich, E.

Publications and source records attributed to Ehrlich, E..

15 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1978

Search and rescue by satellite

A system of satellites, ground stations and user equipments is proposed to provide an operational demonstration, using existing technology, for the timely detection and position location of general aviation aircraft and marine distress incidents so that rescue efforts can be started as soon as possible. The spaceborne equipment will consist of a transponder capable of receiving signals from existing and planned distress beacons at 121.5, 243.0 and 406.0 MHz, and transmitting at 1543 MHz. The program has generated international interest with Canada, France and the USSR presently planning to participate jointly with the U.S. in the development of the space and ground hardware.

Ehrlich, E.↗
NASA NTRS1976

Satellites for distress alerting and locating: Report by Interagency Committee for Search and Rescue Ad Hoc Working Group

The background behind the congressional legislation that led to the requirement for the Emergency Locator Transmitter (ELT) and the Emergency Position-Indicating Radio Beacon (EPIRB) to be installed on certain types of aircraft and inspected marine vessels respectively is discussed. The DAL problem is discussed for existing ELT and EPIRB equipped aircraft and ships. It is recognized that the DAL requirement for CONUS and Alaska and the maritime regions are not identical. In order to address the serious DAL problem which currently exists in CONUS and Alaska, a low orbiting satellite system evolves as the most viable and cost effective alternative that satisfies the overall SAR system design requirements. A satellite system designed to meet the needs of the maritime regions could be either low orbiting or geostationary. The conclusions drawn from this report support the recommendation to proceed with the implementation of a SAR orbiting satellite system.

Ehrlich, E.↗
NASA NTRS1975

Advanced communications experiments for Spacelab

The Spacelab design and mission capabilities appear to provide a practical vehicle for meeting communication experiment needs. Results of recent discussions and numerous contractual activities have conclusively corroborated the potential useful role that a manned laboratory in space can afford to the communications community. Some examples of the experiments that appear presently as strong candidates for early flights on the Spacelab missions of the 1980s are discussed. Particular attention is given to radio frequency interference, bandwidth compressive modulation, laser experimentation, and use of large deployable communications antenna. It can be expected that the Spacelab will reduce the time, risk, and cost for conducting some communications experiments and developing the related space technology.

Ehrlich, E.↗
NASA NTRS1974

Spacelab communications experiments

The Space Shuttle launched Spacelab is planned to provide the communications community with a platform to develop the technology required for NASA's and DOD's missions, and future domestic and international communications satellites in the 1980s. The Laboratory, with a weight carrying capability of 14,500 kg into a low-earth orbit and return to earth, is being planned to carry laser telescopes; large (greater-than 10 meter) deployable antennas; spaceborne receivers to map terrestrial noise sources in a variety of frequency bands, and other advanced technology applicable to the 1980s and 1990s. Spacelab will also facilitate ease of comparative testing between alternative or competing experiments, subsystems and components prior to a commitment to an automated satellite.

Ehrlich, E.↗
NASA NTRS1972

The role of time-frequency in satellite position determination systems.

Tests were conducted by NASA on radio navigation satellite systems that employ the use of time-frequency determination. The satellites used for this purpose were the ATS 1 and 3, and the Nimbus 3 and 4. Several systems were tested in order to examine the feasibility of three satellite navigation concepts: (1) multiple satellite range measurements, (2) satellite range rate, or range and range rate measurements and (3) satellite angle measurements. Test results indicate that locations of ships and aircraft can be determined to within 3-5 km, one sigma, by these satellite methods, and that location accuracy is both a function of the RF employed and of the extent of knowledge of the satellite orbit.

Ehrlich, E.↗
NASA NTRS1968

Satellite aids for aviation.

Satellite system providing combined communications, weather and navigational services for commercial aircraft

Ehrlich, E.↗
NASA NTRS1967

Navigation satellites - The future.

Navigation satellites for information during movements of manned/unmanned terrestrial vehicles containing position determination, communications and weather relay service and scientific sensors

SCIENTIFIC SATELLITE↗
NASA NTRS1967

Satellite aids to transportation.

Vehicular traffic and rail transportation surveillance or coordination aids possibilities using earth orbiting satellite

SURVEILLANCE↗
NASA NTRS1967

Navigation by satellite.

Satellite navigation systems requirements including Loran, inertial navigation and Navy systems

INERTIAL NAVIGATION↗