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Otoshi, T. Y.

Publications and source records attributed to Otoshi, T. Y..

54 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

Development and evaluation of a set of group delay standards

A set of cable assemblies serving as group delay standards having nominal delays of 15, 30, and 60 nsec are described. Various types of measurements were performed on the cable standards, including impedance, microwave phase shift, RF pulse burst delay, modulation pulsed delay, and envelope phase shift measurements. The results of these tests are given, and various sources of error are discussed, in particular, dispersion and internal reflections.

Otoshi, T. Y.↗
NASA NTRS1975

A collection of articles on S/X-band experiment zero delay ranging tests, volume 1

Articles are presented which are concerned with the development of special test equipment and a dual-frequency zero delay device (ZDD) that were required for range tests and the measurement of ground station delays for the Mariner-Venus-Mercury 1973 S/X-band experiment. Test data obtained at DSS 14 after installation of the ZDD on the 64-m antenna are given. It is shown that large variations of range were observed as a function of antenna elevation angle and were sensitive to antenna location. A ranging calibration configuration that was subsequently developed and a technique for determining the appropriate Z-correction are described. Zero delay test data at DSS 14 during the Mariner 10 Venus-Mercury-Encounter periods (1974 days 12-150) are presented. The theoretical analysis and experimental verifications are included of the effects of multipath and effects of discontinuities on range delay measurements. A movable subreflector technique and the multipath theory were used to isolate principal multipath errors on the 64-m antenna and to enable a more accurate determination of the actual ground station range delay.

Otoshi, T. Y.↗
NASA NTRS1975

Effect of discontinuities on the group delay of a microwave transmission line

The problem is considered of the effect of reflections from discontinuities at each end of a transmission line on the group delay at microwave frequencies. Previous work is briefly reviewed and a general analysis is made. Graphical data are presented based upon the formulas developed. Experimental results are given which confirm the theory.

Beatty, R. W.↗
NASA NTRS1972

A study of microwave leakage through perforated flat plates.

A simple formula useful for predicting leakage through a circular hole array in a metallic flat plate is presented. A correction is given for plate thickness. The formula is applicable to arrays having either a 60-deg (staggered) or 90-deg (square) hole pattern, but is restricted to the case of (1) an obliquely incident plane wave with the E field polarized normal to the plane of incidence, and (2) large transmission loss. When theoretical values were compared to experimental data obtained on test samples having transmission losses greater than 20 dB, the agreement between theory and experiment was typically better than 1 dB at S band and 2 dB at X band.

Otoshi, T. Y.↗
NASA NTRS1970

Radiometric evaluation of antenna-feed component losses

Radiometric method accurately calibrates the principal line sections of an antenna, including the section which contains the antenna-feed component /mode generator and polarizer/. Precise knowledge of the absolute antenna temperature is not required.

Otoshi, T. Y.↗
NASA NTRS1969

The effect of mismatched components on microwave noise-temperature calibrations

Analysis of errors on microwave noise-temperature measurements is important due to development of very low-noise antenna receiving systems and in the absolute accuracies to which the noise temperatures of these systems can be calibrated. Scattering parameters describe properties of the microwave network connected between noise source and receiver.

Otoshi, T. Y.↗