Publications
CW operation of monolithic arrays of surface-emitting AlGaAs diode lasers with dry-etched vertical facets and parabolic deflecting mirrors
Summary
Summary
A monolithic two-dimensional array of surface-emitting AlGaAs diode lasers with dry-etched vertical facets and parabolic deflecting mirrors was mounted junction-side up on a W / Cu microchannel heatsink and evaluated under continuous-wave (CW) operating conditions. Both the facets and parabolic deflecting mirrors were etched using chlorine ion-beam-assistd etching. Threshold current...
Optimal searches for asteroids
Summary
Summary
Optimal searches for a fixed object are discussed and the rigorous analytical results of discrete search theory are presented. They show that the totally optimal, the uniformly optimal, the locally optimal, and the fastest searches are identical under not too restrictive assumptions. The mathematical formalism is illustrated by an Earth-approaching...
A new asteroid observation and search technique
Summary
Summary
A prototype observatory was constructed near Socorro, New Mexico to search for and observe earth-approaching asteroids. Hardware modifications were made so that the discrimination of artificial satellites at an angular speed of 15 arcsec/sec can be used to observe minor planets at an angular speed of 0.01 arcsec/sec. Assuming no...
Low elevation angle measurement limitations imposed by the troposphere - and analysis of scintillation observations made at Haystack and Millstone
Summary
Summary
Tropospheric angle-of-arrival and amplitude scintillation measurements were made at X-band (7.3 GHz) and at UHF (0.4 GHz). The measurements were made using sources on satellites with 12-day orbits. The angle of arrival of the ray path to a satellite changed slowly allowing observations of fluctuations caused by atmospheric irregularities as...