S-193 impulse response cross correlation

The author has identified the following significant results. A significant result was the realization that the phase information, normally lost in envelope detection and sampling, could have been preserved if the samples were taken at the peaks of the carrier frequency at intervals equal to a twice or an integral multiple of the integral number of its period. Thus the Skylab S193 Model 1 altimeter data does not contain phase information in accordance with the technical information obtained from NASA and Lockheed technical personnel. Another significant discovery was to learn that the eight return pulse samples don't belong to the same pulse but represent an average over many pulses

Probable deviations in altitude reading given by the LM altimeter for the most rough surface along a certain given trajectory

Random noise calculations in altitude reading of lunar module altimeter for rough surfaces targe

Lunar landing module reflectivity model

Lunar landing module reflectivity model based on Surveyor and Orbiter photographs of lunar craters, hills, and boulder

Plane wave scattering from a rough surface with correlated large and small scale orders of roughness

Plane wave scattering from rough surface with correlated large and small scale orders of roughnes

Lunar terrain and reflectivity study Final report

Lunar landing trajectory, landing module electronics and Doppler radar, and probable landing sites modeled for ultrasonic simulatio

Simulated LM static reflectivity data, for site P-2-6

Simulated lunar module static reflectivity data for site P-2-

Cross-correlative analysis of S-193 data for terrain characteristics

The author has identified the following significant results. The impulse response technique, when coupled with fine resolution altimeter data, is capable of yielding: (1) very fine mean ground elevation resolution; (2) slopes and slope variation along the altimeter path; (3) the absorption or the ground vegetation cover density for a given weather condition; and (4) an eventual classification of ground cover and/or moisture content of the ground

Ultrasonic simulation of MSBLS multipath fading for orbiter landing configuration

The on-shuttle antenna pattern of the MSBLS receiver, and the azimuth and elevation beamwidths were simulated by their corresponding ultrasonic transducer beams. The scanning rate for the azimuth and elevation beams was 1.75 degrees/second. The results were adjusted for full-scale maximum sinusoidal scan rates of 691 and 377 deg/sec for AZ and EL respectively. The rain drops were simulated by air bubbles, with a similar size distribution, in water. The rain volume was created along a part of the propagation path, and not on the runway, because it was found difficult to avoid an accumulation of bubbles on the runway surface and surroundings simulated by the model surface. Multipath fading from the ground, and its possible degrading effect on the orbiter received beam shape and the associated landing guidance parameters is discussed

Terrain bias on Doppler system output

Terrain bias on Doppler system output obtained by transmit-receive syste