Accession Number : AD0634240

Title :   EXPECTED INSTRUMENT ACCURACY OF MICROWAVE DISTANCERS,

Corporate Author : OHIO STATE UNIV COLUMBUS DEPT OF GEODETIC SCIENCE

Personal Author(s) : Laurila, Simo H.

Report Date : DEC 1965

Pagination or Media Count : 103

Abstract : Humidity effect in microwave distancers was evaluated and found to cause phase shifting in the cyclic error variation. Cyclic error variation was found to be present in MRA-1, MRA-2 and MRA-3 Tellurometers reaching values up to + or -20 cm. The repetition of measurements at different weather conditions and by extending the line 15 meters with one meter intervals between measurements proved to improve the results essentially in MRA-1 and MRA-2 operations. The extension of the line 10 meters in MRA-3 operations and the use of interchangeable Master/Remote functioning proved to be necessary to obtain the ultimate accuracy. The resolution capability of the MRA-1 and MRA-2 Tellurometers is about + or -2.3 cm, while the allover standard error for one observation is about + or -7.5 cm. The resolution capability of MRA-3 Tellurometer is about + or -1.3 cm and the allover standard error for one observation is about + or -1.5 cm. The standard error for one observation in Electrotape DM-20 seems to be about + or -0.8 cm. The use of microwave absorbents or reflection plates has been found to reduce the reflection errors from solid or moving objects. (Author)

Descriptors :   (*MICROWAVES, PROPAGATION), (*DISTANCE MEASURING EQUIPMENT, *MICROWAVE EQUIPMENT), CALIBRATION, RADIO WAVES, HUMIDITY, ATMOSPHERIC REFRACTION, SURVEYING(GEOGRAPHIC), GEODESICS, PHASE SHIFT CIRCUITS, ERRORS

Subject Categories : Geodesy
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE