Engineering topics

Aronson, A. I.

Publications and source records attributed to Aronson, A. I..

2 records

NASA NTRS1974

Very high resolution radiometer

A primary sensor used in environmental and earth-resource observation, the Very High Resolution Radiometer (VHRR) was designed for use on the ITOS D series spacecraft. The VHRR provides a 0.47 mile resolution made possible with a mercury-cadmium-telluride detector cooled to approximately 105 K by a passive radiator cooler. The components of this system are described. The optical subsystem of the VHRR consists of a scanning mirror, a Dall-Kirkham telescope, a dichroic beam splitter, relay lenses, spectral filters, and an IR detector. Signal electronics amplify and condition the signals from the infrared and visible light detector. Sync generator electronics provides the necessary time signals. Scan-drive electronics is used for commutation of the motor winding, velocity, and phase control. A table lists the performance parameters of the VHRR.

Aronson, A. I.↗

NASA NTRS1973

Very high resolution radiometer /VHRR/

Discussion of the design and performance of the very high resolution radiometer (VHRR) representing the first of a second-generation of infrared scanning radiometers of high performance. Following a description of the optical, signal-electronics, sync-generator, scan-drive, cooler, and contamination-protection design, it is pointed out that the two VHRRs presently operating have logged a total of 15,500 hrs of continuous successful operation since launch. The cooler operation has been particularly noteworthy. The cold plate heater power, required to maintain the detectors at 105 K, has undergone in almost a year's operation so small a degradation as to indicate a VHRR cooler lifetime exceeding the instrument design lifetime of one year by a large margin. High resolution, low noise, and jitter-free pictures are shown to have been derived from these instruments.

Aronson, A. I.↗