Space station tracking requirements feasibility study, volume 1

The objective of this feasibility study is to determine analytically the accuracies of various sensors being considered as candidates for Space Station use. Specifically, the studies were performed whether or not the candidate sensors are capable of providing the required accuracy, or if alternate sensor approaches be investigated. Other topics related to operation in the Space Station environment were considered as directed by NASA-JCS. The following topics are addressed: (1) Space Station GPS; (2) Space Station Radar; (3) Docking Sensors; (4) Space Station Link Analysis; (5) Antenna Switching, Power Control, and AGC Functions for Multiple Access; (6) Multichannel Modems; (7) FTS/EVA Emergency Shutdown; (8) Space Station Information Systems Coding; (9) Wanderer Study; and (10) Optical Communications System Analysis. Brief overviews of the abovementioned topics are given. Wherever applicable, the appropriate appendices provide detailed technical analysis. The report is presented in two volumes. This is Volume 1, containing the main body and Appendices A through J

Space station tracking requirements feasibility study, volume 2

The objective of this feasibility study is to determine analytically the accuracies of various sensors being considered as candidates for Space Station use. Specifically, the studies were performed whether or not the candidate sensors are capable of providing the required accuracy, or if alternate sensor approaches should be investigated. Other topics related to operation in the Space Station environment were considered as directed by NASA-JSC. The following topics are addressed: (1) Space Station GPS; (2) Space Station Radar; (3) Docking Sensors; (4) Space Station Link Analysis; (5) Antenna Switching, Power Control, and AGC Functions for Multiple Access; (6) Multichannel Modems; (7) FTS/EVA Emergency Shutdown; (8) Space Station Information Systems Coding; (9) Wanderer Study; and (10) Optical Communications System Analysis. Brief overviews of the abovementioned topics are given. Wherever applicable, the appropriate appendices provide detailed technical analysis. The report is presented in two volumes. This is Volume 2, containing Appendices K through U

Spacecraft applications of advanced global positioning system technology

The purpose of this study was to evaluate potential uses of Global Positioning System (GPS) in spacecraft applications in the following areas: attitude control and tracking; structural control; traffic control; and time base definition (synchronization). Each of these functions are addressed. Also addressed are the hardware related issues concerning the application of GPS technology and comparisons are provided with alternative instrumentation methods for specific functions required for an advanced low earth orbit spacecraft

Transverse Optical Mode Patterns for an RF Excited Ar-He-Xe Laser

Transverse optical modes for an RF excited Ar-He-Xe laser are studied both experimentally and theoretically. A diffraction model for a waveguide with a nonsaturable gain and refractive index gradients placed between two plane mirrors is formulated. The effects of gain and diffraction index gradients and of diffraction in free space are evaluated for typical experimental conditions. A direct comparison between theoretical mode patterns and experimentally measured ones at distances of 17 and 114 cm from the output mirror demonstrated a satisfactory agreement for various laser wavelengths and gas mixture composition

The fabrication of patterned metallic master by photolithography and electroplating technique for making PDMS-stamp as a tool for drug delivery system preparation

In this work, the micropatterned (Ni micropillars) masters were fabricated by combination of photolithography and electroplating technique. The polydimethylsiloxane (PDMS) stamps were successfully made by casting technique on micropatterned masters and used for further preparation of polymeric microchamber arrays film considered to be a drug delivery system. Micropatterned master fabrication is more precise technique, which is necessary for defects elimination

Coherent Demodulation for Orthogonal Sideband and Carrier Tracking

International Telemetering Conference Proceedings / November 14-16, 1978 / Hyatt House Hotel, Los Angeles, CaliforniaA demodulation technique which permits simultaneous coherent and orthogonal tracking of a suppressed carrier and of the associated sidebands is described. The performance of a demodulator based on such a technique is defined for a general case and for a specific case of two-channel FM multiplexing. Experimental data supporting the analysis of the FM multiplexing mode of the demodulator is presented and discussed.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection

DIGITAL HILBERT TRANSFORMER FOR SINGLE-SIDEBAND GENERATION

International Telemetering Conference Proceedings / October 24-27, 1983 / Sheraton-Harbor Island Hotel and Convention Center, San Diego, CaliforniaThis paper describes a digital real-time implementation of a Hilbert transformer for the generation of single-sideband signals (SSB’s). Design criteria for the transformer are presented and the experimental results are discussed for a typical voice-band channel having a nominal bandwidth of 300 to 3500 Hz. Techniques for generating two independent sidebands (ISB’s) on a single carrier are also described.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection

Microprocessor-Based Analog Voice Scrambling Techniques

International Telemetering Conference Proceedings / November 19-21, 1979 / Town and Country Hotel, San Diego, CaliforniaAnalog voice privacy techniques provide the advantage of being compatible with the 3 kHz audio bandwidth of the existing radio and telephone channels. The degree of privacy provided by an analog voice scrambling technique, however, is proportional to the number of time and frequency elements into which the voice signal can be divided as well as to the number of permutation patterns according to which the elements are scrambled. This implies the requirement for a high degree of signal-processing capability. Microprocessorbased implementations of an analog voice scrambling device provide a large potential for signal processing and scrambling. Furthermore, they provide this potential at a reasonable cost, small volume and moderate power consumption. In addition, a single microprocessorbased analog voice privacy device can be configured in software to yield various degrees of privacy, depending on a particular use and circumstances. Also, a variety of auxiliary functions such as timing, code generation, synchronization and analog-to-digital conversion can be time-shared within the same microprocessor chip, thus minimizing the requirement for support hardware. The purpose of this paper is twofold: (1) to provide an overview of the existing analog voice privacy techniques, and (2) to specifically outline the capabilities of the microprocessor-based analog voice privacy system design, with a particular emphasis on achieving an analog scrambled signal compatible with the 3 kHz nominal audio bandwidth of the existing radio and telephone channels. Also, workable algorithms used for microprocessor-based analog voice scrambling in frequency as well as in time domain are described. Tape recordings of the voice scrambled and recovered with these algorithms are presented for comparison.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection

RECENT DEVELOPMENTS IN NARROWBAND ANALOG SIGNAL ENCRYPTION WITH EMPHASIS ON VOICE CHANNEL SYSTEMS

International Telemetering Conference Proceedings / October 13-15, 1981 / Bahia Hotel, San Diego, CaliforniaIn many instances, the process of telemetering of scientific information must be accompanied by a voice conversation which either reveals the sequence of measurements or provides information as to the nature of the data gathered and/or transmitted. If such voice information can compromise the integrity of the telemetry data to an unauthorized interceptor, voice privacy equipment must be used along with the equipment used for transmission of the telemetry data. The recent developments in LSI technology provide a new capability to the design of voice encryption equipment. This is particularly true for the case where sophisticated analog encryption schemes must be employed to permit the encrypted voice information to be transmitted over the existing telephone and radio channels which are typically limited to a 3 KHz upper-frequency cutoff. This paper examines the recent developments in analog voice privacy equipment design, as indicated by the disclosures made in open literature by various manufacturers and evaluators of such equipment. Advances in the technology as well as in analytical definitions of analog voice privacy are discussed. The role of such valuable LSI chips as a microprocessor and the DES algorithm are examined. Also, in addition to considering the classic frequency/time domain permutation algorithms, developments in analog “pseudonoise” scrambling are examined in view of the data made recently available in open literature.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection

Space Shuttle Payload Communication Links

International Telemetering Conference Proceedings / November 14-16, 1978 / Hyatt House Hotel, Los Angeles, CaliforniaOne mission of the Shuttle is to place payloads into Earth orbit or on escape trajectories and to recover payloads from Earth orbit. In order to properly deploy and retrieve such payloads, operational and diagnostic communications must take place between the payloads and the Shuttle. The results of such communications, in the form of tracking, commands, and telemetry, will be interpreted both aboard the Shuttle and on the ground. To accommodate a diverse set of payloads for both NASA and DOD programs, multimode avionic equipment dedicated to payload communications is being installed aboard the Shuttle. This equipment, operating at RF and baseband and providing capability for digital and analog signal forms, will furnish all required capabilities to communicate with both attached and detached payloads.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection