Microwave power transmission system wherein level of transmitted power is controlled by reflections from receiver

A microwave, wireless, power transmission system is described in which the transmitted power level is adjusted to correspond with power required at a remote receiving station. Deviations in power load produce an antenna impedance mismatch causing variations in energy reflected by the power receiving antenna employed by the receiving station. The variations in reflected energy are sensed by a receiving antenna at the transmitting station and used to control the output power of a power transmitter

The effects of high energy particles on planetary missions

Researchers review the background and motivation for the detailed study of the variability and uncertainty of the particle environment from a space systems planning perspective. The engineering concern raised by each environment is emphasized rather than the underlying physics of the magnetosphere or the sun. Missions now being planned span the short term range of one to three years to periods over ten years. Thus the engineering interest is beginning to stretch over periods of several solar cycles. Coincidentally, detailed measurements of the environment are now becoming available over that period of time. Both short term and long term environmental predictions are needed for proper mission planning. Short term predictions, perhaps based on solar indices, real time observations, or short term systematics, are very useful in near term planning -- launches, EVAs (extravehicular activities), coordinated observations, and experiments which require the magnetosphere to be in a certain state. Long term predictions of both average and extreme conditions are essential to mission design. Engineering considerations are many times driven by the worst case environment. Knowledge of the average conditions and their variability allows trade-off studies to be made, implementation of designs which degrade gracefully under multi-stress environments

Wavelength error analysis in a multiple-beam Fizeau laser wavemeter having a linear diode array readout

An estimate of the wavelength accuracy of a laser wavemeter is performed for a system consisting of a multiple-beam Fizeau interferometer and a linear photosensor array readout. The analysis consists of determining the fringe position errors which result when various noise sources are included in the fringe forming and detection process. Two methods of estimating the fringe centers are considered: (1) maximum pixel current location, and (2) average pixel location for two detectors with nearly equal output currents. Wavelength error results for these two methods are compared for some typical wavemeter parameters

FET charge sensor and voltage probe

A MOSFET structure having a biased gate covered with an insulator is described. The insulator is of such a thickness as to render the structure capable of giving a measure of accumulated charge. The structure is also capable of being used in a stacked structure as a particle spectrometer

Pioneer Venus spacecraft charging model

Five environmental models were constructed to represent the solar wind and the upper, middle, and lower ionosphere of Venus. The spacecraft structure was modeled with over 140 passive electrical elements representing structural elements of the spacecraft. Electron, ion, secondary electron, and photocurrents to the spacecraft from the plasma were calculated, ignoring sheath effects. In all but one case, potentials of interest were less than 1 volt. Potential differences between widely separated points on the equipment shelf were less than 1 mV. The one area of concern is the solar panel potential when the orbiter is passing through the bowshock region

Old Chief, Crowder, and Trials by Stipulation

In this Article, Professor Robinson argues that the meaning of unfair prejudice and the scope of trial judges\u27 discretion in employing Rule 403 of the Federal Rules of Evidence is still uncertain following the Supreme Court\u27s recent decision in United States v. Old Chief and its vacation and remand of United States v. Crowder and United States v. Davis. Robinson evaluates the evidentiary implications of the Supreme Court\u27s recent decisions by discussing each case and analyzing the implications of the three cases read together. Professor Robinson examines the possible effects of stipulations and admissions on the Rule 403 balancing test for exclusion of relevant evidence, highlighting the distinctions of the stipulations in Old Chief as compared to those in Crowder and Davis. In addition, he discusses the appropriate role of emotionally laden evidence in trial processes. He also ponders the scope of trial judges\u27 discretion to exclude evidence under Rule 403 after Old Chief, Crowder, and Davis. Finally, Professor Robinson analyzes the possible interpretations of Old Chief, from a very narrow reading to a very broad one, to conclude that read with Crowder and Davis, the ruling in Old Chief was relatively conservative and will likely be limited by the Court in future decisions to its specific facts or to other cases involving legal status issues. As such, traditional practices remain largely undisturbed. Robinson notes that the Court articulated a cautious rationale for reversing the conviction in Old Chief and explains that far more sweeping change could have been effected if the court had applied differently the definition of relevancy in Rule 401 or, alternatively, the balancing test of Rule 403. Robinson concludes that Old Chief clearly means that trial judges do not have unlimited discretion to decline to exclude evidence under Rule 403 but that the extent of this limitation must await the clarification of further decision