Inertial gyroscope system application considerations

Criteria for designing inertial gyroscope system

POINTING, ACQUISITION, AND TRACKING FOR DIRECTIONAL WIRELESS COMMUNICATIONS NETWORKS

Directional wireless communications networks (DWNs) are expected to become a workhorse of the military, as they provide great network capacity in hostile areas where omnidirectional RF systems can put their users in harm's way. These networks will also be able to adapt to new missions, change topologies, use different communications technologies, yet still reliably serve all their terminal users. DWNs also have the potential to greatly expand the capacity of civilian and commercial wireless communication. The inherently narrow beams present in these types of systems require a means of steering them, acquiring the links, and tracking to maintain connectivity. This area of technological challenges encompasses all the issues of pointing, acquisition, and tracking (PAT). iii The two main technologies for DWNs are Free-Space Optical (FSO) and millimeter wave RF (mmW). FSO offers tremendous bandwidths, long ranges, and uses existing fiber-based technologies. However, it suffers from severe turbulence effects when passing through long (>kms) atmospheric paths, and can be severely affected by obscuration. MmW systems do not suffer from atmospheric effects nearly as much, use much more sensitive coherent receivers, and have wider beam divergences allowing for easier pointing. They do, however, suffer from a lack of available small-sized power amplifiers, complicated RF infrastructure that must be steered with a platform, and the requirement that all acquisition and tracking be done with the data beam, as opposed to FSO which uses a beacon laser for acquisition and a fast steering mirror for tracking. This thesis analyzes the many considerations required for designing and implementing a FSO PAT system, and extends this work to the rapidly expanding area of mmW DWN systems. Different types of beam acquisition methods are simulated and tested, and the tradeoffs between various design specifications are analyzed and simulated to give insight into how to best implement a transceiver platform. An experimental test-bed of six FSO platforms is also designed and constructed to test some of these concepts, along with the implementation of a three-node biconnected network. Finally, experiments have been conducted to assess the performance of fixed infrastructure routing hardware when operating with a physically reconfigurable RF network

The 60 GHz antenna system analyses for intersatellite links, phase B

The purpose of this study is first to investigate, classify, and compare applicable antenna systems capable of establishing and maintaining intersatellite links at 60 GHz and secondly to select the most applicable system for a detailed conceptual design. The results are to be applicable to the development of intersatellite links at 60 GHz for future programs. Design goals are listed

NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 07)

This bibliography is issued in two sections: Section 1 - Abstracts, and Section 2 - Indexes. This issue of the Abstract Section cites 158 patents and applications for patent introduced into the NASA scientific and technical information system during the period of January 1975 through June 1975. Each entry in the Abstract Section consists of a citation, an abstract, and, in most cases, a key illustration selected from the patent or application for patent. This issue of the Index Section contains entries for 2830 patent and application for patent citations covering the period May 1969 through June 1975. The index section contains five indexes -- subject, inventor, source, number and accession number

Severe storms observing satellite (STORMSAT)

The primary payload for this satellite is the Advanced Atmospheric Sounding and Imaging Radiometer which will perform precise infrared temperature sounding and visible/infrared imaging from geostationary orbit. A secondary payload instrument which may be utilized on STORMSAT is the Microwave Atmospheric Sounding Radiometer which provides an independent set of temperature and humidity sounding in cloudy, meteorologically active regions. The study provides satellite designs and identifies mission-unique subsystems using the Multimission Modular Spacecraft using a Shuttle/Interim Upper Stage launch vehicle

Advanced Gas Turbine (AGT) powertrain system

A 74.5 kW(100 hp) advanced automotive gas turbine engine is described. A design iteration to improve the weight and production cost associated with the original concept is discussed. Major rig tests included 15 hours of compressor testing to 80% design speed and the results are presented. Approximately 150 hours of cold flow testing showed duct loss to be less than the design goal. Combustor test results are presented for initial checkout tests. Turbine design and rig fabrication is discussed. From a materials study of six methods to fabricate rotors, two have been selected for further effort. A discussion of all six methods is given

The 31st Aerospace Mechanisms Symposium

The proceedings of the 31st Aerospace Mechanisms Symposium are reported. Topics covered include: robotics, deployment mechanisms, bearings, actuators, scanners, boom and antenna release, and test equipment. A major focus is the reporting of problems and solutions associated with the development and flight certification of new mechanisms

Orbital assembly and maintenance study

The requirements, conceptual design, tradeoffs, procedures, and techniques for orbital assembly of the support structure of the microwave power transmission system and the radio astronomy telescope are described. Thermal and stress analyses, packaging, alignment, and subsystems requirements are included along with manned vs. automated and transportation tradeoffs. Technical and operational concepts for the manned and automated maintenance of satellites were investigated and further developed results are presented