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NASA NTRS2003

Wireless Phone Threat Assessment and New Wireless Technology Concerns for Aircraft Navigation Radios

To address the concern for cellular phone electromagnetic interference to aircraft radios, a radiated emission measurement process was developed for two dominant digital standards of wireless handsets. Spurious radiated emissions were efficiently characterized from devices tested in either a semi-anechoic or reverberation chamber, in terms of effective radiated power. Eight representative handsets (four from each digital standard) were commanded to operate while varying their radio transmitter parameters (power, modulation, etc.). This report provides a detailed description of the measurement process and resulting data, which may subsequently be used by others as a basis of consistent evaluation of other portable transmitters using a variety of wireless transmission protocols. Aircraft interference path loss and navigation radio interference threshold data from numerous reference documents, standards, and NASA partnerships were compiled. Using these data, a preliminary risk assessment is provided for wireless phone interference to aircraft Localizer, Glideslope, Very High Frequency Omni directional Range, and Global Positioning Satellite radio receivers on typical transport airplanes. The report identifies where existing data for device emissions, interference path loss, and navigation radio interference thresholds need to be extended for an accurate risk assessment for wireless transmitters in aircraft.

Ely, Jay J.↗

NASA NTRS1982

Tire Temperature and Pressure Monitor

Wheel-mounted miniature transmitter would signal dangerous conditions to the driver or pilot. Monitor would include a sensor and a radio transmitter mounted so as not to imbalance the wheel. Sensor and batteries are enclosed in a plastic housing on the rim. Also has possibilities as a research tool for experiements on vehicle safety.

Macconochie, I. O.↗

NASA NTRS1976

Omega navigation for general aviation

A 70-hour flight test evaluation of an Omega navigation system was performed using a Piper Cherokee 180, to determine the feasibility of Omega for worldwide general aviation navigation. Measurements were made of position accuracy, noise phenomena, and signal to noise ratio. It was found that Omega accuracy is essentially insensitive to local geography, but that there are isolated local interference phenomena associated with radio transmitters, although the strongest noise source observed was due to the onboard power source for the VHF comm/nav radio. An occurrence of lane jumps was observed when attempting to navigate with one weak station.

Hollister, W. M.↗

NASA NTRS1972

Telemetry in animal and human biometeorology

Radio transmitters swallowed, surgically implanted, or carried externally make it possible to study a subject with minimum disturbance to normal patterns of activity. The radio frequency of transmission chosen will depend on the application, and will generally fall in the range from 50 kHz to 300 MHz. A number of specific experiments are reported, including the case of a snake which has swallowed a mouse containing a transmitter of pressure and temperature. Questions of monitoring are explored. Satellite Doppler tracking considerations are discussed together with the attachment of the transmitter package in the case of a study of birds.

Mackay, R. S.↗

NASA NTRS1985

Waves In Space Plasmas (WISP)

Waves in space plasmas (WISP) utilizes powerful radio transmitters and sensitive receivers to probe the secrets of the magnetosphere, ionosphere and atmosphere. The scientific objective is to achieve a better understanding of the physical processes occurring in these regions. For example, audio frequency radio waves will be radiated from the long WISP antenna, will travel to the outer reaches of the magnetosphere, and will interact with Van Allen belt particles, releasing some of their energy which amplifies the waves. Study of this interaction will give us a better understanding of a major magnetospheric process, wave particle interactions. Radio waves from WISP at higher frequencies (AM radio and beyond) will be reflected by the ionosphere and will, for example, advance our understanding of bubbles in the equatorial ionosphere which affect satellite communications.

Taylor, W. W. L.↗

NASA NTRS1986

Waves In Space Plasmas (WISP)

Waves in space plasmas (WISP) utilizes powerful radio transmitters and sensitive receivers to probe the secrets of the magnetosphere, ionosphere and atmosphere. The scientific objective is to achieve a better understanding of the physical processes occurring in these regions. For example, audio frequency radio waves will be radiated from the long WISP antenna, will travel to the outer reaches of the magnetosphere, and will interact with Van Allen belt particles, releasing some of their energy which amplifies the waves. Study of this interaction will give a better understanding of a major magnetospheric process, wave-particle interactions. Radio waves from WISP at higher frequencies (AM radio and beyond) will be reflected by the ionosphere and will, for example, advance our understanding of bubbles in the equatorial ionosphere which affect satellite communications.

Taylor, W. W. L.↗

NASA NTRS2000

Some Notes on Sparks and Ignition of Fuels

This report compliments a concurrent analysis of the electromagnetic field threat to the fuel system of a transport aircraft. The accompanying effort assessed currents, voltages and power levels that may be induced upon fuel tank wiring from radio transmitters (inside and outside the aircraft). In addition to this, it was also essential to determine how much voltage, current, or power is required to create a fuel-vapor ignition hazard. The widely accepted minimum guideline for aircraft fuel-vapor ignition is the application of a 0.2 millijoule energy level. However, when considering radio frequency (RF) sources, this guideline is seriously inadequate. This report endeavors to bridge the gap between a traditional understanding of electrical breakdown, heating and combustion; and supplement the knowledge with available information regarding aircraft fuel-vapor ignition by RF sources

Fisher, Franklin A.↗

NASA NTRS1972

Detection and analysis of Jupiter's decametric micropulses

The occurrence of Jupiter's decametric radio emission can be correlated with the central meridian longitude of Jupiter as if the active regions were radio transmitters placed at fixed longitudes on its surface. These active regions are commonly called sources and are labelled Source A, Jovian longitude = 200 deg, Source B = 100 deg and Source C =300 deg. These sources are not always active. However, they can be turned-on if Jupiter's innermost Galilean moon, Io, is in the right phase. In fact, if Io is found 90 deg from superior geocentric conjunction (maximum eastern elongation) and if source B is simultaneously on the central meridian, source B radiation is almost guaranteed, whereas source C radiation is highly likely when Io is found 240 deg from superior geocentric conjunction. Source A radiation is largely independent of Io's position. Interestingly, the Io-related radio storms contain unusually rapid events that can only be properly studied using wide-band techniques.

Lebo, G. R.↗

DOE OSTI2023

Solar Farm Development Impacts on Eastern Box Turtle ( Terrapene carolina ) Home Ranges

Eastern Box Turtle (Terrapene carolina) populations have declined drastically since 1970 because of continued destruction and fragmentation of their habitat. Although they are known to shift their home ranges because of environmental degradation, it is unknown how solar arrays impact Eastern Box Turtles. From 2011–2018, we collected data on Eastern Box Turtle movement and occupancy in a 79-ha solar farm. The solar farm is divided into six fenced areas, each containing wildlife openings for movement of terrestrial fauna every 23 m around the fenced solar arrays. For this work, we hypothesized that the solar arrays changed the home range sizes of turtles that interacted with the field. We fitted 41 Eastern Box Turtles with radio transmitters and tracked their locations twice per week in June–August from 2011–2018. Seventeen turtles had home ranges that overlapped with the solar arrays whereas 24 turtles had home ranges that never interacted with the solar arrays. We calculated home range sizes and tested for differences between overlapping and nonoverlapping groups. We further considered if the number of observations within the solar farm impacted home range size and displacement. We found that Eastern Box Turtles that used the solar farm exhibited 55–83% larger home ranges on average than turtles in natural habitats, but there was no significant association of home range size with the amount of time observed within the solar farm. Finally, we discuss strategies to mitigate negative impacts of solar farm development on turtles.

Radio telemetry↗

NASA NTRS1968

Automatic patient respiration failure detection system with wireless transmission

Automatic respiration failure detection system detects respiration failure in patients with a surgically implanted tracheostomy tube, and actuates an audible and/or visual alarm. The system incorporates a miniature radio transmitter so that the patient is unencumbered by wires yet can be monitored from a remote location.

Dimeff, J.↗

NASA NTRS1972

Long distance tracking of birds

The application of radio telemetry techniques to the long distance tracking of birds is discussed. The types of equipment developed and methods for attachment to a bird are described. The operating range of the radio transmitter receiver system is examined, and methods for acquiring and analyzing the data are explained.

Cochran, W. W.↗

NASA NTRS1971

Bio-medical telemetry: Sensing and transmitting biological information from animals to man

The application of small radio transmitters for monitoring biological activity in animals and humans is discussed. The microminiaturization of the electronic transmitters makes it possible for them to be swallowed and to operate within the body with no external connections. The small size also makes it possible for the transmitters to be surgically implanted or carried externally to monitor specific bodily functions. The use of satellites to monitor the activity of birds and animals carrying small transmitters is described. Photographs of birds, fish, and reptiles which were equipped with miniature electronic monitors are provided.

Mackay, S.↗

NASA NTRS1971

Bio-medical telemetry - Sensing and transmitting biological information from animals and man.

Several examples are presented of radio transmitters swallowed, surgically implanted, or carried externally to study animal and human objects with minimum disturbance to normal activity patterns. Particular attention is given to the method of using satellite-borne receivers for determining the position of animals or other objects carrying fixed-frequency transmitters. The design and operation of the instrumentation necessary for this purpose are described.

Mackay, S.↗

NASA NTRS1976

Tracking system for moving subjects

Electronic system automatically focuses camera or spotlight on moving object. Subject is equipped with miniature ultrasonic or radio transmitter; its signal is picked up by two or more detectors, is phase detected and fed into computer which determines position of subject and sends command signals to servo for camera or spotlight.

Mogavero, L. N.↗

NASA NTRS1977

A tactile paging system for deaf-blind people, phase 2

Control logic and the on-body radio transmitter is investigated. The control logic capability and studied methods for implementing the on-body portion of the logic in a small package are improved. A small low power, on-body transmitter was designed, developed, and tested with a wrist-strap antenna to extend the one-way communication system developed during Phase 1 to a two-way communication system.

Baer, J. A.↗

NASA NTRS1977

Effect of suprachiasmatic lesions on diurnal heart rate rhythm in the rat

Heart rate and locomotor activity of rats kept under 12L/12D illumination regimen were recorded every six minutes for ten days using implantable radio transmitters. Some of the rats then received bilateral RF lesions into the suprachiasmatic nucleus (SCN). Control sham operations were performed on the rest of the animals. After recovery from surgery, recording of heart rate and locomotor activity was continued for ten days. SCN-lesioned rats showed no significant diurnal fluctuation in heart rate, while normal and sham-operated rats showed the normal diurnal rhythm in that function. The arrhythmic diurnal heart-rate pattern of SCN rats appeared to be correlated with their sporadic activity pattern. The integrity of the suprachiasmatic nucleus is therefore necessary for the generation and/or expression of diurnal rhythmicity in heart rate in the rat.

Saleh, M. A.↗

NASA NTRS1977

A subcutaneous channeling probe for implanting long leads

The channeling probe described in the present paper was designed to overcome surgical problems of the type that were encountered when a multichannel radio transmitter had to be implanted in a cow. The probe was made of a flexible but sufficiently stiff 9.5-mm-diam nylon rod, consisting of 46-cm sections for convenience in sterilization and surgical handling. Stainless steel sleaves reinforced the threaded connecting joints. At one end, arrowhead-shaped channeling heads could be attached to produce wide channels for large sensors. The other end was tapered for narrow channels. Postoperative problems were not encountered in the use of this probe in cows, sheep, and dogs.

Lund, G. F.↗

NASA NTRS1980

Computer-controlled warmup circuit

Filament of high-power radio transmitter is brought to operating temperature automatically. Pushbotton reduces operator's role to one-step command and is compatible with various forms of computer control. Filiament shutdown is initiated by "down" command from operator, failure of cooling systems, or power failure for more than few seconds.

Daeges, J. J.↗