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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.
1

REVIEW OF BANDWIDTH EFFICIENT MODULATION SCHEMES

Osborne, William P., Ara, Sharmin 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / The national telemetry ranges are being pushed to provide higher data rate telemetry services by users with increasingly complex test procedure for increasingly complex weapon systems. At the same time they are having trouble obtaining more spectrum in which to provide these higher rates because of the demand for spectrum in SHF range from various mobile/cellular Personal Communications Services (PCS) as well as congress’s desire to auction spectrum and to transfer as much spectrum as possible to commercial uses. In light of these pressures the industry is in need of a modulation standard that will out perform the existing PCM/FM standard. The motivation for the present review and analysis of the performance of various coded/uncoded modulation schemes arises from this issue. Comparison of the performance of these schemes will be utilized in the following work to find a suitable solution to the existing problem.
2

ADJACENT CHANNEL INTERFERENCE MEASUREMENTS WITH CPFSK AND FQPSK-B SIGNALS

Law, Eugene 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper will present measured data in an adjacent channel interference (ACI) environment for both filtered continuous phase frequency shift keying (CPFSK) and Feher’s patented quadrature phase shift keying (FQPSK-B) [1]. The quantity measured was bit error probability (BEP) versus signal energy per bit to noise power spectral density ratio (E(b)/N(o)). The interferers were either CPFSK or FQPSK-B signals. The results presented in this paper will be for bit rates of 5 Mb/s, one interferer 20 dB larger than desired signal, various channel spacings, and two different telemetry receivers. The ACI test effort will collect data sets at several bit rates and with one and two interferers. The results will be useful to system designers and range operators as they attempt to maximize the number of Mb/s that can be simultaneously transmitted in the telemetry bands.
3

RECOMMENDED MINIMUM TELEMETRY FREQUENCY SPACING WITH CPFSK, CPM, SOQPSK, AND FQPSK SIGNALS

Law, Eugene 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper will present equations for calculating the minimum recommended frequency separation of two digital telemetry signals. The signals can be filtered continuous phase frequency shift keying (CPFSK), multi-h continuous phase modulation (CPM) [1], shaped offset quadrature phase shift keying-Telemetry Group (SOQPSK-TG, aka SOQPSK-A*) [2], or Feher’s patented quadrature phase shift keying FQPSK-B (or FQPSK-JR [3]). The equations are based on measured data in an adjacent channel interference (ACI) environment for filtered CPFSK (aka PCM/FM), multi-h CPM (or CPM for short), SOQPSK-TG, FQPSK-JR, and FQPSK-B. This paper is an extension of my 2001 and 2002 International Telemetering Conference papers on this topic [4, 5]. The quantity measured was bit error probability (BEP) versus frequency separation at a given signal energy per bit to noise power spectral density ratio (Eb/No). The interferers were CPFSK, CPM, SOQPSK-TG or FQPSK-B (-JR) signals. The results presented in this paper will be for a desired signal bit rate of 1 to 20 Mb/s, one interferer 20 dB larger than the desired signal (a few tests included two interferers), and various center frequency spacings, interfering signals, receivers, and demodulators. The overall ACI test effort has collected data sets at several bit rates and with one and two interferers. The results will be useful to system designers and range operators as they attempt to maximize the number of Mb/s that can be simultaneously transmitted with minimal interference in the telemetry bands.
4

ADJACENT CHANNEL INTERFERENCE MEASUREMENTS WITH CPFSK, CPM AND FQPSK-B SIGNALS

Law, Eugene 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / This paper will present measured data in an adjacent channel interference (ACI) environment for filtered continuous phase frequency shift keying (CPFSK or FM), multi-h continuous phase modulation (multi-h CPM or CPM for short) [1] and Feher’s patented quadrature phase shift keying (FQPSK-B) [2]. This paper is an extension of my 2001 International Telemetering Conference paper on this topic [3]. The quantity measured was bit error probability (BEP) versus signal energy per bit to noise power spectral density ratio (E(b)/N(o)). The interferers were CPFSK, CPM, or FQPSK-B signals. The results presented in this paper will be for a desired signal bit rate of 5 Mb/s, one interferer 20 dB larger than desired signal (a few tests included two interferers), and various center frequency spacings, interfering signals, receivers, and demodulators. The overall ACI test effort will collect data sets at several bit rates and with one and two interferers. The results will be useful to system designers and range operators as they attempt to maximize the number of Mb/s that can be simultaneously transmitted with minimal interference in the telemetry bands.
5

Trellis Coded Multi-h CPFSK via Matched Codes

Hsieh, Jeng-Shien 19 July 2000 (has links)
The continuous phase frequency shift keying (CPFSK) is a modulation method with memory. The memory results from the phase continuity of the transmitted carrier phase from one signal interval to the next. For a specific form of phase, CPFSK becomes a special case of a general class of continuous phase modulation (CPM) signals. In this thesis, we extend the decomposition model of single-h CPM to the multi-h CPM decomposition model. Based on this decomposition model approach the multi-h CPFSK schemes are evaluated by searching the desired multi-h phase codes at a given number of states. Moreover, the trellis coded multi-h CPFSK schemes, which are the combination of the (binary) convolutional codes with the multi-h CPFSK schemes, are searching by optimization procedure via the matched encoding method. To further improve the performance, in terms of the coding gain, the ring convolutional codes are applied to the continuous phase encoder (CPE) of the proposed multi-h CPFSK schemes. Due to the fact that the code structure of the ring convolutional codes is similar to the CPE, this will result in having simple and efficient combination of the convolutional codes with the multi-h CPFSK signaling schemes.

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