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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Capture Method for Spread Spectrum Aloha Signals

Weibing, Fan, Qishan, Zhang 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / The concept and model of Spread Spectrum ALOHA (SS-ALOHA), as an important subject to develop dual-purpose satellite system in China, are described in this paper. The new synchronous code format and method for capturing the SS-ALOHA signals are presented and the process of correlation with surface-audio wave (SAW) is shown. The diagram of fast acquisition system and the results of experiment are given.
72

SUBMINIATURE TELEMETRY FOR MULTIPLE MUNITION (TECHNOLOGY TRANSITION)

Cullen J. M., Keller, Ed 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / The Instrumentation Technology Branch of Wright Laboratory Armament Directorate (WL/MNSI), has successfully completed an Exploratory Development (6.2) program to develop Subminiature Telemetry (SMT). SMT is a flexible, programmable telemeter with self calibration, power control and Direct Sequence Spread Spectrum modulation. The development program successfully demonstrated the ability of the SMT system to collect up to 64 analog and/or 128 digital discrete signals with programmable gain, bandwidth and offset. The program demonstrated a spread spectrum multiple-access technique that allows for simultaneous transmission and receipt of up to 96 different telemetry units within a 100 MHz telemetry band. WL/MNSI is conducting an Advanced Technology Development (6.3) program to continue development in this area. An air-worthy 4 channel spread spectrum demodulator was developed to support the SMT program but it is too costly for ground applications. The goals of this effort are to reduce the demodulator cost by a factor of 10 while increasing the capability for simultaneously processing data from 24 telemetry units and to support the first Technology Transition Plan (TTP) between WL/MN and the Air Force Development Test Center (AFDTC). The TTP will facilitate the transition of SMT spread spectrum technology to AFDTC for mission support over the next three years.
73

SPREAD SPECTRUM TT&C FOR THE SKYBRIDGE CONSTELLATION

Nasta, R., Gillot, J.-F. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The SKYBRIDGE constellation will establish telecommunication and TTC links in Kuband, without any exclusive allocation of spectrum: jamming avoidance techniques are used in order to protect the geostationary satellites and associated ground stations that work in the same band. This paper presents the studies that have been carried out at system level.
74

A METHOD TO ENHANCE THE BIT RATE OF LINEAR CODE GENERATOR IN SPREAD-SPECTRUM COMMUNICATION SYSTEM

Xiaoyu, Dang, Yong, Zhang, Tingxian, Zhou 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Because of the limits of feedback devices, high-speed pseudo-noise code generators cannot depend simply on the improvement of clock rate. Based on the characteristic equation of linear feedback registers and the m-sequence sampling theory as well, deduction is made to indicate a novel way to improve the speed of pseudo-noise code generators 2^l (2^l < n, n is the length of registers) times as fast as the conventional one. Also, we extend our applications to non-reducible and non-primitive polynomials. It could be a good way to generate these linear codes at higher rates.
75

A PCMCIA BASED TELEMETRY AND ACQUISITION SYSTEM

Gross, Jeffrey, Keller, G. E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / In this paper, the Miniature Data Acquisition Transceiver System (Mini-DAT), a Type II PC-Card based data acquisition and transceiver system is described. The Mini-DAT was developed by ViaSat and is currently in use at the Air Force Research Lab (AFRL) at Eglin AFB. AFRL is investigating the use of this Industrial, Scientific and Medical (ISM) band system for data collection with advanced munitions. The Mini-DAT combines the advantages of PC-Card technology with an off the shelf interfacing and packaging approach to provide a large array of capabilities in a very small package. The system provides everything needed to collect analog, discrete and digital data, process the data and transfer the data in a wireless fashion using the latest license free spread spectrum modulation technology. The advanced design of the Mini-DAT allows for operation in harsh remote environments, collecting data unattended and accessed remotely. A graphical user interface (GUI) is provided via a Windows 3.x and 95 software package that can be easily customized for specific applications. The Mini-DAT provides fast and reliable error-free data transfer over the 2.4GHz ISM communication band. It operates over a shared 80MHz bandwidth, allowing multiple access of a number of portable units operating simultaneously in the same band.
76

A SYNCHRONOUS REAL TIME NETWORK BASED WIRELESS AIRBORNE DATA ACQUISTION SYSTEM

Long, Mark A., Zymowski, Paul H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The purpose of this paper is to present a chronology from a Small Business Innovation Research Program (SBIR) showing the impact of a wireless network architecture on future airborne data acquisition systems. The major advantages and challenges associated with the use of wireless network data acquisition versus wired time division multiplexing systems are rooted in data latency, bandwidth efficient data transmission while maintaining a low bit error rate and not interfering with existing avionics. Many of the issues raised are subtle and complex. It is not the intent of this paper to give these issues the thorough academic and technical analysis they deserve. It is the hope of the authors that this paper will generate awareness and discussion on these issues.
77

Maximum-likelihood detection for multiuser communication systems. / CUHK electronic theses & dissertations collection

January 2001 (has links)
Ma Wing Kin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 150-155). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
78

Code Acquisition of a DS/SS Signal with Transmit and Receive Antenna Diversity

Ikai, Youhei, Katayama, Masaaki, Yamazato, Takaya, Ogawa, Akira 12 1900 (has links)
No description available.
79

Measured noise performance of a data clock circuit derived from the local M-sequence in direct-sequence spread spectrum systems

Harshbarger, Stuart D. January 1990 (has links) (PDF)
Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, September 1990. / Thesis Advisor(s): Myers, Glen. Second Reader: Ha, Tri. "September 1990." Description based on title screen as viewed on December 21, 2009. DTIC Identifiers: Direct sequence spread spectrum, data clocks, delay lock loops, sequence generators. Author(s) subject terms: Direct-sequence spread spectrum, communications, data clock recovery, M-sequence, delay-lock loop, spread spectrum, binary sequence generation. Includes bibliographical references (p. 40). Also available in print.
80

Spread Spectrum Signal Detection from Compressive Measurements

Lui, Feng 10 1900 (has links)
ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / Spread Spectrum (SS) techniques are methods used to deliberately spread the spectrum of transmitted signals in communication systems. The increased bandwidth makes detection of these signals challenging for non-cooperative receivers. In this paper, we investigate detection of Frequency Hopping Spread Spectrum (FHSS) signals from compressive measurements. The theoretical and simulated performances of the proposed methods are compared to those of the conventional methods.

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