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1

Ghuman, Parminder, Salman Sheikh, Steve Koubek, Scott Hoy, and Andrew Gray. "High Rate Digital Demodulator ASIC." International Foundation for Telemetering, 1998. http://hdl.handle.net/10150/609676.

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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California
The architecture of the High Rate (600 Mega-bits per second) Digital Demodulator (HRDD) ASIC capable of demodulating BPSK and QPSK modulated data is presented in this paper. The advantages of all-digital processing include increased flexibility and reliability with reduced reproduction costs. Conventional serial digital processing would require high processing rates necessitating a hardware implementation other than CMOS technology such as Gallium Arsenide (GaAs) which has high cost and power requirements. It is more desirable to use CMOS technology with its lower power requirements and higher gate density. However, digital demodulation of high data rates in CMOS requires parallel algorithms to process the sampled data at a rate lower than the data rate. The parallel processing algorithms described here were developed jointly by NASA’s Goddard Space Flight Center (GSFC) and the Jet Propulsion Laboratory (JPL). The resulting all-digital receiver has the capability to demodulate BPSK, QPSK, OQPSK, and DQPSK at data rates in excess of 300 Mega-bits per second (Mbps) per channel. This paper will provide an overview of the parallel architecture and features of the HRDR ASIC. In addition, this paper will provide an overview of the implementation of the hardware architectures used to create flexibility over conventional high rate analog or hybrid receivers. This flexibility includes a wide range of data rates, modulation schemes, and operating environments. In conclusion it will be shown how this high rate digital demodulator can be used with an off-the-shelf A/D and a flexible analog front end, both of which are numerically computer controlled, to produce a very flexible, low cost high rate digital receiver.
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2

Harwood, Luke. "Chaos-based phase-shift keying compatible with conventional receiver architectures." Thesis, University of Bristol, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601184.

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Despite the lack of a universal mathematical framework for the analysis of chaotic systems, development of analysis techniques has been swift due both to the research interest in chaos theory from many diverse subjects and to the vast computing resources now available. However, many potential applications remain in the realm of theory. This thesis provides a link between chaos theory and communication systems, with the aim of developing a modulation technique capable of implementation with current technology. Although potentially very simple, chaotic systems result in extremely complex behaviour, resulting in loss of predictability in the long term. Their sensitive dependence on initial conditions enables large-scale changes to be effected with small control perturbations, and their aperiodic behaviour results in broad power spectra. The potential for an electronically simple chaos-based transmitter architecture, employing direct modulation of the passband chaotic oscillator, provides the motivation for this research. Building on the fundamental properties and analysis tools of chaotic systems, an intuitive exploration of the chaos generation mechanisms of several single-scroll chaotic attractors is developed, leading to the creation of several novel chaotic attractors and a discussion of their applications. The concept of a flexible chaotic oscillator-based transmitter architecture which is compatible with standard synchronisation and demodulation techniques is considered, and the resulting noise performance of both simulation and hardware implementations found to be competitive with standard modulation techniques. Additionally, a powerful baseband simulation technique is proposed and implemented, leading to the suggestion of a digital baseband implementation of the transmitter and its potential applications. , Avenues of further work are identified, providing direction for improvements of the proposed system and other related branches worthy of further study.
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3

Lichtenberg, Sören [Verfasser]. "Manipulation of Holographic Gratings using Phase-shift Keying / Sören Lichtenberg." Aachen : Shaker, 2007. http://d-nb.info/1170528287/34.

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4

Jung, Du San. "Detection of binary phase-shift keying signal in multipath propagation." Monterey, California: Naval Postgraduate School, 2002, 2002. http://hdl.handle.net/10945/9763.

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Time-varying dispersion and multipath propagation in a shallow underwater environment causes intersymbol interference in underwater communication. This thesis investigates a mitigation procedure for communication using a Binary Phase-Shift Keying (BPSK) signal. The method employed uses the time-reversed ocean impulse response to mitigate the degradation of the bit error rate performance. All results were achieved by the use of computer simulation of typical shallow water environments.
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5

Jung, Du San. "Detection of binary phase-shift keying signal in multioath propagation." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Jun%5FJung.pdf.

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6

Vacondio, Francesco. "On the benefits of phase shift keying to optical telecommunication systems." Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/27653/27653.pdf.

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Les avantages de la modulation de phase vis-à-vis la modulation d’intensité pour les réseaux optiques sont claires et accepté par la communauté scientifique des télécommunications optiques. Surtout, la modulation de phase montre une meilleure sensibilité au bruit, ainsi qu’une plus grande tolérance aux effets non-linéaires que la modulation d’intensité. Nous présentons dans cette thése un étude qui vise à développer les avantages de la modulation de phase. Nous attaquons d’abord la complexité du récepteur en détection directe, en proposant une nouvelle configuration dont la complexité est comparable à celle du récepteur pour la modulation d’intensité traditionnel, mais avec des meilleures performances. Cette solution pourrait convenir pour les réseaux métropolitains (et même d’accès) à haut débit binaire. Nous passons ensuite à l’examen de la possibilité d’utiliser des amplificateur à semi-conducteur (SOA) au lieu des amplificateurs à fibre dopée à l’erbium pour fournir amplification optique aux signaux modulés en phase. Les non-linéarité des SOA sont étudiées, et un compensateur simple et très efficace est proposé. Les avantages des amplificateurs à semi-conducteur par rapport à ceux à fibre sont bien connus. Surtout, la méthode que nous proposons permettrait l’integrabilité des SOA avec d’autres composants de réseau (par exemple, le récepteur nommé cidessus), menant à des solutions technologiques de petite taille et efficaces d’un point de vue énergétique. Il y a deux types de systèmes pour signaux modulés en phase: basé sur la détection directe, ou sur les récepteurs cohérents. Dans le dernière partie de ce travail, nous nous concentrons sur cette dernière catégorie, et nous comparons deux solutions possibles pour la mise à niveau des réseaux terrestres actuel. Nous comparons deux configurations dont les performances sont très comparables en termes de sensibilité au bruit, mais nous montrons comment la meilleure tolérance aux effets non linéaires (en particuliers dans les systèmes à débit mixte) fait que une solution soit bien plus efficace que l’autre.
The advantages of phase modulation (PM) vis-à-vis intensity modulation for optical networks are accepted by the optical telecommunication community. PM exhibits a higher noise sensitivity than intensity modulation, and it is more tolerant to the effects of fiber nonlinearity. In this thesis we examine the challenges and the benefits of working with different aspects of phase modulation. Our first contribution tackles the complexity of the direct detection noncoherent receiver for differentially encoded quadrature phase shift keying. We examine a novel configuration whose complexity is comparable to that of traditional receivers for intensity modulation, yet outperforming it. We show that under severe nonlinear impairments, our proposed receiver works almost as well as the conventional receiver, with the advantage of being much less complex. We also show that the proposed receiver is tolerant to chromatic dispersion, and to detuning of the carrier frequency. This solution might be suitable for high-bit rates metro (and even access) networks. Our second contribution deals with the challenges of using semiconductor optical amplifiers (SOAs) instead of typical erbium doped fiber amplifiers (EDFAs) to provide amplification to phase modulated signals. SOAs nonlinearities are investigated, and we propose a simple and very effective feed-forward compensator. Above all, the method we propose would permit the integrability of SOAs with other network components (for example, the aforementioned receiver) achieving small size, power efficient sub-systems. Phase modulation paves the way to high spectral efficiency, especially when paired with digital coherent receivers. With the digital coherent receiver, the degree of freedom offered by polarization can be exploited to increase the channel bit rate without increasing its spectral occupancy. In the last part of this work we focus on polarization multiplexed signaling paired with coherent reception and digital signal processing. Our third contribution provides insight on the strategies for upgrading current terrestrial core networks to high bit rates. This is a particularly challenging scenario, as phase modulation has to coexist with previously installed intensity modulated channels. We compare two configurations which have received much attention in the literature. These solutions show comparable performance in terms of back-to-back noise sensitivity, and yet are not equivalent. We show how the superior tolerance to nonlinear fiber propagation (and particularly to cross phase modulation induced by the presence of intensity modulated channels) makes one of them much more effective than the other.
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7

Davidson, H. D. "A reliable data channel for underwater communications using phase shift keying." Thesis, University of Newcastle Upon Tyne, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233423.

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8

Bottenfield, Joe, and Vern Moore. "SMALL VOLUME, FEHER-PATENTED QUADRATURE PHASE SHIFT KEYING, JR VERSION, TELEMETRY TRANSMITTER." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/606734.

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International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada
This paper describes the implementation of a Feher-Patented Quadrature Phase Shift Keying (FQPSK) waveform variant that reduces overall design complexity, which in turn results in a telemetry transmitter that provides all the benefits of the existing FQPSK-B waveform, in a 3.0 x 2.0 x 1.0 volume. This variant is referred to the as the FQPSK-JR version. This waveform differs from the “near constant” envelop response of the qualified Herley airborne FQPSK-B telemetry transmitter in terms of the time domain wavelet transition functions and the amplitude scaling term associated with those functions. The end result is a “constant envelop” design, which employs simplified antialias filtering and more efficient digital design techniques.
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9

Liu, Niu. "Undersampled differential phase shift on-off keying for optical camera communications with phase error detection." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/60143.

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This thesis introduces the design and implementation of an optical camera communication (OCC) system. Phase uncertainty and phase slipping caused by camera sampling are the two major challenges for OCC. In this thesis, we propose a novel modulation scheme to overcome these problems. The undersampled differential phase shift on-off keying is capable of encoding binary data bits without exhibiting any flicker to human eyes. The phase difference between two consecutive samples conveys one-bit information which can be decoded by a low frame rate camera receiver. Error detection techniques are also introduced in the thesis to enhance the reliability of the system. Furthermore, we present the hardware and software design of the proposed system. This low-cost communication system has been implemented with a Xilinx FPGA and a Logitech commercial camera. Experimental results demonstrate that a bit-error rate of 10-⁵ can be achieved with 7.15 microwatts received signal power over a link distance of 15 centimeters.
Applied Science, Faculty of
Engineering, School of (Okanagan)
Graduate
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10

Rodenbaugh, John Irvin. "Optimum detection of differentially-encoded M-ary phase-shift keying in a dispersive aeronautical channel." Ohio : Ohio University, 2002. http://www.ohiolink.edu/etd/view.cgi?ohiou1174934375.

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11

黃俊賢 and Chun-yin Vong. "Performance study of uniform sampling digital phase-locked loopsfor [Pi]/4-differentially encoded quaternary phase-shift keying." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31221816.

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12

Dudak, Celal. "Effects Of Solid State Power Amplifier Nonlinearity On Various Phase Shift Keying Modulation Schemes." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12605860/index.pdf.

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This study concentrates on the performance evaluation of a specific modulation scheme under nonlinear operation. This modulation scheme is the phase shift keying (PSK) modulation, exemplified by the special cases of BPSK, QPSK, OQPSK, &
#960
/4-QPSK. The specific nonlinear block is chosen to be the solid state power amplifier (SSPA) structure whose simulation model is the Rapp model. Varying transmitter filter characteristic and one of the power amplifier parameters constitute the main methodology of simulations. Bit error rate (BER), error vector magnitude (EVM), and Space Frequency Coordination Group (SFCG) spectral mask constraint are the evaluation parameters taken into account throughout this study. Simulation results support the initial literature survey, which reveals additional features showing how each modulation scheme is affected by various SSPA nonlinearity characteristics.
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13

Berhanu, Samuel, and Kamal Neupane. "Digital Radio Implementation for NASA S-Band Space Network Transceiver." International Foundation for Telemetering, 2012. http://hdl.handle.net/10150/581843.

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The system diagrams for the digital radio compatible with NASA's S-Band Space Network operating from 2025.8 - 2117.9 MHz (forward link) to 2200 - 2300 MHz (return link) are presented. The digital radio implementation includes binary phase shift keying (BPSK), quadrature phase shift keying (QPSK) and staggered quadrature phase shift keying (SQPSK). We have derived the system requirements for these modulation schemes from the Space Network User Guide (SNUG) and thereafter, derived system diagrams for the communication links. The designed system diagrams for the transceiver were implemented using Simulink models and USRP2 platform.
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14

Ekanthalingam, Ravikanth. "Amplitude Estimation of Minimum Shift Keying in the presence of Co-channel interference." Ohio University / OhioLINK, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1107802525.

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15

Bishop, Chris, and Mike Fahey. "AN EXTENSION OF SOQPSK TO M-ARY SIGNALLING." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/605808.

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International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada
Shaped Offset Quadrature Phase Shift Keying (SOQPSK) has the advantages of low sidelobes and high detection probability; however, its main lobe has a fixed width set by the number of constellation points. By slightly modifying the modulation scheme, the four constellation points of quadrature shift keying can be changed to M constellation points where M is a power of 2. After this change, the power spectral density (PSD) retains low sidelobes, and the desirable property of being able to detect the signal by integrating over two symbol periods is retained.
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16

Vong, Chun-yin. "Performance study of uniform sampling digital phase-locked loops for [Pi]/4-differentially encoded quaternary phase-shift keying /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20007164.

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17

Croussore, Kevin. "ALL-OPTICAL REGENERATION FOR PHASE-SHIFT KEYED OPTICAL COMMUNICATION SYSTEMS." Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2481.

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All-optical signal processing techniques for phase-shift keyed (PSK) systems were developed theoretically and demonstrated experimentally. Nonlinear optical effects in fibers, in particular four-wave mixing (FWM) that occurs via the ultra-fast Kerr nonlinearity, offer a flexible framework within which numerous signal processing functions can be accomplished. This research has focused on the regenerative capabilities of various FWM configurations in the context of processing PSK signals. Phase-preserving amplitude regeneration, phase regeneration, and phase-regenerative wavelength conversion are analyzed and demonstrated experimentally. The single-pump phase-conjugation process was used to regenerate RZ-DPSK pulse amplitudes with different input noise distributions, and the impact on output phase characteristics was studied. Experiments revealed a limited range over which amplitude noise could effectively be suppressed without introduction of phase noise, particularly for signals with intensity pattern effects. Phase regeneration requires use of phase-sensitive amplification (PSA), which occurs in nonlinear interferometers when the pump and signal frequencies are degenerate (NI-PSA), or in fiber directly through single-stage (degenerate) or cascaded (non-degenerate) FWM processes. A PSA based on a Sagnac interferometer provided the first experimental demonstration of DPSK phase and amplitude regeneration. The phase-regenerative capabilities of the NI-PSA are limited in practice by intrinsic noise conversion (amplitude to phase noise) and to a lesser extent by the requirement to modulate the pump wave to suppress stimulated Brillouin scattering (SBS). These limitations are relaxed in novel materials with higher SBS thresholds and nonlinearities. Degenerate FWM provides PSA in a traveling-wave configuration that intrinsically suppresses the noise conversion affecting the NI-PSA, while providing stronger phase-matched gain. Experiments confirmed superior phase-regenerative behavior to the NI-PSA with simultaneous reduction of amplitude noise for NRZ-DPSK signals. Phase-regenerative wavelength conversion (PR-WC) provides the regenerative properties of PSA at a new wavelength, and was proposed and demonstrated for the first time in this research. The parallel implementation of two FWM processes, phase-conjugation and frequency conversion, provides two idlers which exhibit interesting and useful regenerative properties. These were investigated theoretically and experimentally. Ideal phase-regenerative behavior is predicted when the contributing FWM processes are equally phase-matched, which can be maintained over any interaction length or wavelength shift provided the pump powers are properly adjusted. Depleted-pump regime PR-WC provides simultaneous phase and amplitude regeneration. Experiments confirmed regenerative behavior for wavelength shifts of the idlers up to 5 nm. Two techniques for phase regeneration of 4-level PSK signals were developed and evaluated. The first is based on parallel operation of PSAs suitable for processing 2-level PSK signals, where phase projection and regeneration are combined to recover the input data. Analysis of this scheme outlined the conditions required for effective phase regeneration and for practical implementation using known PSAs. A novel process based on FWM (parallel phase-conjugation followed by PSA) was developed and analyzed, and demonstrated using numerical simulations. These studies provide a basis for further work in this area.
Ph.D.
Optics and Photonics
Optics and Photonics
Optics PhD
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18

Milivojevic, Biljana. "Study of optical differential phase shift keying transmission techniques at 40 Gbit/s and beyond." kostenfrei, 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=977176231.

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19

Monica, G. Della, and E. Tonello. "NEW GENERATION COMMAND RECEIVER FOR SATELLITE USING BENEFITS OF DIGITAL PROCESSING." International Foundation for Telemetering, 1998. http://hdl.handle.net/10150/607344.

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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California
Presentation of Alcatel Espace last studies and developments regarding TT&C receiver Products for satellite. This document lays on 3 parts: · a technical point of view showing digital demodulation principles used (base band recovery, analytical head, PM or FM demodulation) and their related offered possibilities(digital controlling loop, lock status detection, jammer detection,....) · a technology/design description · a synthesis showing performance and results
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20

Chagnon, Mathieu. "Digital signal processing assessment for optical coherent receiver using dual-polarization Quadrature phase shift keying modulation." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97202.

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In this work, we evaluate different approaches of digital signal processing applied after a coherent receiver in order to recover the binary information of an optical signal modulated in Dual-Polarization Quadrature Phase Shift Keying. We explain in details the functioning of a coherent receiver as well as the optical and electrical signals travelling inside. We present the criteria of the two lasers employed for modulation and demodulation, i.e., the signal and local oscillator lasers, as a function of the modulation format and the binary rate. We expose all the required signal processing for information recovery out of a coherent receiver and mention those who will be assessed in this work, along with the reason of their selection. Subsequently, the metric to assess the different methods is introduced. The latter is twofold and consists of the computational complexity and the final bit error rate that each approach yields. The schematics of the test bed follows in parallel with the parameter space of our setup. The computational complexity and the bit error rate of ten different approaches are presented, and an optimal configuration of methods and parameters to use for such modulation and receiver is deduced.
Dans ce travail, nous évaluons différentes approches de traitement de signaux numériques pour un récepteur cohérent optique dans le but de recouvrir l'information binaire d'un signal modulé sur double polarization et quatre niveaux de phase, ou « Dual-Polarization QPSK ». Nous expliquons en détail le fonctionnement d'un récepteur cohérent ainsi que les signaux optiques et électriques qui s'y propagent. Nous présentons les critères des deux lasers utilisés pour la modulation et la démodulation cohérente, i.e., les lasers signal et oscillateur local, en fonction du format de modulation utilisé et du taux binaire. Nous exposons tous les traitements de signaux numériques requis pour recouvrir l'information sortant d'un récepteur cohérent et mentionnons ceux qui seront évalués dans ce travail ainsi que les raisons de leur sélection. Par la suite, nous introduisons la métrique d'évaluation des différentes approches. Cette dernière comporte deux facettes, soit la complexité de calcul des différents algorithmes et paramètres utilisés ainsi que le taux d'erreur binaire final que l'ensemble des processus produisent lorsqu'une certaine approche est employée. La présentation schématique du banc de test suit de concert avec l'espace des paramètres du montage. La complexité de calcul et le taux d'erreur binaire de dix différentes approches sont présentés et une configuration optimale des paramètres et méthodes pour un tel format de modulation et receveur est déduite.
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21

Kocakanat, Murat. "A direct sequence - code division multiple access/binary phase shift keying (DS-CDMA/BPSK) modem design." Monterey, California. Naval Postgraduate School, 1997. http://hdl.handle.net/10945/8270.

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22

Wree, Christoph [Verfasser]. "Differential Phase-Shift Keying for Long-Haul Fiber Optic Transmission Based on Direct Detection / Christoph Wree." Aachen : Shaker, 2004. http://d-nb.info/1172614946/34.

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23

Jefferis, Robert P. "EVALUATION OF CONSTANT ENVELOPE OFFSET QUADRATURE PHASE SHIFT KEYING TRANSMITTERS WITH A SOFTWARE BASED SIGNAL ANALYZER." International Foundation for Telemetering, 2004. http://hdl.handle.net/10150/605762.

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International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California
Off-line software based signal analysis can be a valuable tool for detailed examination of transmitter signal characteristics. This paper describes the Advanced Range Telemetry (ARTM) Constant Envelope (CE) offset quadrature phase shift keying (OQPSK) modulation analyzer. It was developed expressly for evaluation of FQPSK-B^(1), FQPSK-JR and shaped OQPSK transmitter signals. Rationale for its creation, underlying assumptions, computation methods, and examples of its data products are presented.
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Shaw, Christopher, and Michael Rice. "TURBO-CODED APSK FOR TELEMETRY." International Foundation for Telemetering, 2007. http://hdl.handle.net/10150/604473.

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ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada
This paper considers the use of Amplitude-Phase Shift Keying (APSK) for a telemetry system. Variable rate turbo codes are used to improve the power efficiency of 16- and 32-APSK. We discuss compensation techniques for power amplifier nonlinearities. Simulation results show the improved spectral efficiency of this modulation scheme over those currently defined in telemetry standards.
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Chen, Dijin, James A. McCorduck, and Kamilo Feher. "FQPSK ANALOG/DIGITAL IMPLEMENTATIONS FOR LOW TO ULTRA HIGH DATA RATES IN 1Gb/s RANGE SYSTEMS." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/606735.

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International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada
For simpler implementations of ultra high bit rate systems, combined analog/digital techniques, described here in, provide implementations with the smallest number of component count utilizing minimal “real-estate” and smallest DC power. While digital implementations with tradition Read Only Memory (ROM) and Digital to Analog Converters (DAC’s) have been proven in several commercial, NASA -CCSDS recommended, and U.S. DoD-IRIG standardized Feher’s QPSK (FQPSK) [2,3] products, such implementations can be further simplified, and in particular for ultra high bit rate product applications. Several waveform generating techniques such as linear approximation, analog approximation and mixed analog and linear approximations are investigated using preliminary simulation results.
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Spáčil, Jan. "Komunikační systémy s digitálními modulacemi." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217453.

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The purpose of this semestral project is to explain the basic issues of simple digital modulations through the creation of simple digital modulations using direct digital synthesis. It begins with a short review of digital modulation theory and the theory about direct digital synthesis. All the technical documentation is attached, including schematics and boards of functional modulator.
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27

Castaneda, Francisco Jose. "Comparison of complementary sequences in hybrid phase and frequency shift keying CW radar using periodic ambiguity analysis." Thesis, Monterey, California. Naval Postgraduate School, 2012. http://hdl.handle.net/10945/27805.

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Continuous waveform (CW) polyphase sequences for radar have a much lower power spectral density (PSD) than pulsed signals but can retain the same target detection capability. The use of different phase values or subcodes to modulate the carrier provides a low probability of intercept (LPI) radar waveform which cannot be seen by a non-cooperative intercept receiver (NCIR). Also, it is a low probability of detection (LPD) waveform due to the low PSD. Frequency shift keying (FSK) radar has a higher PSD but is moved about quickly in frequency over a large bandwidth in which the NCIR cannot follow. Consequently, the FSK (usually a Costas frequency set) remains a LPI signal but not a LPD. To combine the advantages of each waveform, this thesis presents a hybrid FSK/PSK emitter waveform to further the LPI, LPD characteristics. By combining both techniques (PSK/FSK), a high time-bandwidth waveform is constructed that provides better LPI/LPD characteristics than each waveform. The periodic ambiguity function (PAF) is evaluated for three different complementary sequences to modulate a Costas frequency set. The peak time and Doppler sidelobes of the PAF are compared against the P4 polyphase modulation for the Golay complementary sequence (15 dB improvement), the quaternary periodic complementary sequence (16 dB improvement), and the quaternary Golay complementary sequence (18 dB improvement).
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Xu, Tianhua. "DSP based Chromatic Dispersion Equalization and Carrier Phase Estimation in High Speed Coherent Optical Transmission Systems." Doctoral thesis, KTH, Optik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-94835.

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Coherent detection employing multilevel modulation formats has become one of the most promising technologies for next generation high speed transmission systems due to the high power and spectral efficiencies. Using the powerful digital signal processing (DSP), coherent optical receivers allow the significant equalization of chromatic dispersion (CD), polarization mode dispersion (PMD), phase noise (PN) and nonlinear effects in the electrical domain. Recently, the realizations of these DSP algorithms for mitigating the channel distortions in the coherent transmission systems are the most attractive investigations. The CD equalization can be performed by the digital filters developed in the time and the frequency domain, which can suppress the fiber dispersion effectively. The PMD compensation is usually performed in the time domain with the adaptive least mean square (LMS) and constant modulus algorithms (CMA) equalization. Feed-forward and feed-back carrier phase estimation (CPE) algorithms are employed to mitigate the phase noise (PN) from the transmitter (TX) and the local oscillator (LO) lasers. The fiber nonlinearities are compensated by using the digital backward propagation methods based on solving the nonlinear Schrödinger (NLS) equation and the Manakov equation. In this dissertation, we present a comparative analysis of three digital filters for chromatic dispersion compensation, a comparative evaluation of different carrier phase estimation methods considering digital equalization enhanced phase noise (EEPN) and a brief discussion for PMD adaptive equalization. To implement these investigations, a 112-Gbit/s non-return-to-zero polarization division multiplexed quadrature phase shift keying (NRZ-PDM-QPSK) coherent transmission system with post-compensation of dispersion is realized in the VPI simulation platform. In the coherent transmission system, these CD equalizers have been compared by evaluating their applicability for different fiber lengths, their usability for dispersion perturbations and their computational complexity. The carrier phase estimation using the one-tap normalized LMS (NLMS) filter, the differential detection, the block-average (BA) algorithm and the Viterbi-Viterbi (VV) algorithm is evaluated, and the analytical predictions are compared to the numerical simulations. Meanwhile, the phase noise mitigation using the radio frequency (RF) pilot tone is also investigated in a 56-Gbit/s NRZ single polarization QPSK (NRZ-SP-QPSK) coherent transmission system with post-compensation of chromatic dispersion. Besides, a 56-Gbit/s NRZ-SP-QPSK coherent transmission system with CD pre-distortion is also implemented to analyze the influence of equalization enhanced phase noise in more detail.
QC 20120528
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29

Shaw, Christopher. "Synchronization for Burst-Mode APSK." International Foundation for Telemetering, 2009. http://hdl.handle.net/10150/606120.

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ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada
We derive bounds on the performance of data-aided joint estimators for timing offset, carrier phase offset, and carrier frequency offset for use in an APSK packet-based communication link. It is shown that the Cramér-Rao Bound (CRB) is a function of the training sequence, the signal-to-noise ratio (SNR), and the pulse shape. We also compute APSK training sequences of different lengths that minimize the CRB for each of the parameters.
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30

Temple, Kip. "ADVANCED RANGE TELEMETRY (ARTM) TIER I COMPATIBLE DEMODULATOR TESTING AND RESULTS." International Foundation for Telemetering, 2002. http://hdl.handle.net/10150/606309.

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International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California
The Nova HYPERMOD demodulator operates in three modes, the classic pulse-code modulation/frequency modulation (PCM/FM), sometimes known as continuous phase frequency shift keying (CPFSK) mode, shaped offset quadrature phase shift keying (SOQPSK) mode, and continuous phase modulation (CPM) mode. Of interest to this paper is SOQPSK mode which is a waveform similar to the Advanced Range Telemetry (ARTM) Tier I waveform, Feher’s Quadrature Phase Shift Keying, B version (FQPSK-B) revision (Rev) A1. Also considered is another variant, FQPSK-JR. This paper will outline the cross compatibility and resynchronization speed of these waveforms based upon ARTM-adopted demodulator performance tests. The results of these laboratory tests comparing the HYPERMOD demodulator, the enhanced Tier I demodulator, and the current Tier I reference demodulator, both from RF Networks, will be presented.
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31

Biyoghe, Joel S. "Design and implementation of a high data rate QPSK demodulator for nanosatellites." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2744.

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Thesis (Master of Engineering in Electrical Engineering)--Cape Peninsula University of Technology, 2017.
This dissertation presents the development of a quadrature phase shift keying (QPSK) demodulator for nanosatellites that complies with both the limited resources associated with nanosatellites as well as the flexibility and configurability required for a software defined radio (SDR) platform. This research project is a component of a bigger project, which is to develop a high-speed receiver for nanosatellites, and aims to provide a practical solution to the need for communication technologies that support emerging nanosatellite applications, such as Earth observation and communications. The development of the QPSK demodulator follows an all-digital implementation approach. The main reason for selecting this approach is to have a system that is flexible and reconfigurable to comply with the SDR requirements. Another reason for selecting this approach is to comply with the low noise system, low power consumption as well as the small size and weight requirements associated with nanosatellites. The QPSK demodulator is implemented on an IGLOO2 Field Programmable Gate Array (FPGA), due to its robustness to radiation and high-speed capability. Initially, the techniques used to design each subsystem of the QPSK demodulator are selected. Then, algorithms to digitally implement the designed subsystems are produced. Thereafter, the code for the digital QPSK demodulator is written and verified in Matlab first. The simulation of the Matlab-based QPSK demodulator performs satisfactorily. Subsequently, the code to implement the QPSK demodulator on an FPGA (IGLOO2) has been written in Libero, using VHSIC Hardware Description Language (VHDL). The resulting FPGA-based QPSK demodulator has been emulated in Libero (an integration and development environment (IDE) for Microsemi FPGAs) using a test-bench as well as other analysis tools. The test-bench results are visualized using Modelsim. The results show that the demodulator can support data rates up to 13.25 Mbps if 16 samples-per-symbols are used, and up to 26.5 Mbps if 8 samples-per-symbols are used. It also has a very good bit-error-rate performance, which is simulated to be within a factor of 5 of the theoretical limit of QPSK modulation. Finally, the demodulator consumes less than 15 mW at the maximum operating speed. and has been coded to mitigate the effects of space radiation and noise contriution by the demodulator itself.
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32

Feher, Kamilo. "FQPSK Doubles Spectral Efficiency of Telemetry: Advances and Initial Air to Ground Flight Tests." International Foundation for Telemetering, 1998. http://hdl.handle.net/10150/607395.

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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California
FQPSK is the abbreviation for Feher Quadrature Phase Shift Keying (FQPSK) patented systems [1]. Digcom, Inc. licensed FQPSK products demonstrated significant spectral saving and RF power efficient robust BER performance advantages. These bit rate agile modems and Non Linearly Amplified (NLA) transceivers, DSP and hardware implementations, and in some instances “software-radios” (20kb/s to more than 100Mb/s) and RF frequency agile (from 150MHz to more than 40GHz) developments and systems have recently been demonstrated and deployed. The spectral efficiency, i.e., data throughput capability of the 1st generation of FQPSK, as demonstrated in initial Advanced Range Telemetry (ARTM) flight tests, approximately doubles while 2nd generation “FQPSK-2” systems have the potential to quadruple the spectral efficiency of operational PCM/FM telemetry systems and be backward compatible with the 1st generation of FQPSK technologies. It is also demonstrated that the spectral efficiency advantage of FQPSK over that of NLA power efficient GMSK, OQPSK and QPSK modulated transceivers is in the 50% to 300% range and that the potential spectral efficiency advantage of FQPSK-2 over GMSK [1] is in the 200% to 500% range. Based on extensive multi-year studies of alternative solutions for spectral and RF power efficient, robust BER performance systems, several commercial US and international organizations, AIAA, CCSDS, NASA, ESA, CCSDS and various programs of the US Department of Defense (DoD) concluded that FQPSK offers the most spectrally efficient high performance-high speed proven technology solutions and recommended FQPSK standardization for several data links. Initial DoD-ARTM Program Office Air-to-Ground L-band and S-band jet airborne telemetry Test and Evaluation (T&E) data, obtained during the summer of 1998 are briefly highlighted. These include simultaneosly tested FQPSK and PCM/FM. In these tests the following ARTM objectives have been demonstrated: (a) FQPSK approximately doubles the spectral efficiency of currently operational PCM/FM; (b) The Data Link Performance of these two systems is comparable. The American Institute of Aeronautics and Astronautics (AIAA) draft modulation standard recommended to the DoD, NASA and CCSDS, was approved by the AIAA [23]. The AIAA standard recommends “that FQPSK modulation be immediately adopted as the interim increment–1 standard.”
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33

Conka, Tahir. "Performance analysis of noncoherent differential phase shift keying using Post-Detection Selection Combining over a Rayleigh fading channel." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1998. http://handle.dtic.mil/100.2/ADA346398.

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Thesis (M.S. in Electrical Engineering) Naval Postgraduate School, June 1998.
Thesis advisor(s): Tri T. Ha, Ralph D. Hippenstiel. "June 1998." Includes bibliographical references (p. 77). Also available online.
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34

Zhu, Changle. "Performance analysis of subcarrier quadrature phase-shift keying systems with I/Q imbalance over Gamma-Gamma fading channels." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58363.

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The error rate performance is studied for subcarrier intensity modulated (SIM) quadrature phase-shift keying (QPSK) system with in-phase and quadrature (I/Q) imbalance over Gamma-Gamma fading channels. In free-space optical (FSO) communication system, the transmitted signals are typically affected by the atmospheric turbulence over the transmission links. In order to study the system performance analytically, different statistical distributions have been proposed to describe the random variation in signal irradiance due to the scintillation caused by the inhomogeneities in both temperature and pressure along the transmission path. Besides the atmospheric turbulence, other sources can also introduce performance degradation to an FSO system. Using quadrature conversion, the performance of the practical system is affected by the phase and amplitude offsets in the two branches. This phenomenon is referred to as I/Q imbalance. Using direct-conversion transceivers, the I/Q imbalance is unavoidable due to the considerable mismatches between the circuit components. This imbalance can happen at transmitter end, receiver end, or both ends of the transceiver. First, we study the error rate performance for a SIM QPSK system with transmitter I/Q imbalance over the Gamma-Gamma fading channels. Then, the error rate performance of a SIM QPSK system with receiver I/Q imbalance is investigated. Finally, the error rate performance is analyzed for a SIM QPSK system with I/Q imbalance at both ends of the transceiver over the Gamma-Gamma fading channels. Closed-form symbol error rate (SER) expressions are derived by taking into account of both the I/Q imbalance and the fading. It is discovered that the value of the receiver amplitude imbalance is irrelevant to the SER of a subcarrier QPSK system. Truncation error analyses are carried out to ensure the accuracy of the approximate series solutions and support the asymptotic analyses. We also present the numerical results to show the performance improvement using a calibrated transceiver. We will treat these three cases separately since they have slightly different models.
Applied Science, Faculty of
Engineering, School of (Okanagan)
Graduate
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35

Quinteros, Milton I. "Trellis Coded Modulation Schemes Using A New Expanded 16-Dimensional Constant Envelope Quadrature-Quadrature Phase Shift Keying Constellation." ScholarWorks@UNO, 2009. http://scholarworks.uno.edu/td/924.

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In this thesis, the author presents and analyzes two 4-dimensional Constant Envelope Quadrature-Quadrature Phase Shift Keying constellations. Optimal demodulators for the two constellations are presented, and one of them was designed and implemented by the author. In addition, a novel expanded 16-dimensional CEQ2PSK constellation that doubles the number of points without decreasing the distance between points or increasing the peak energy is generated by concatenating the aforementioned constellations with a particular method and restrictions. This original 16-dimensional set of symbols is set-partitioned and used in a multidimensional Trellis-Coded Modulation scheme along with a convolutional encoder of rate 2/3. Effective gain of 2.67 dB over uncoded CEQ2PSK constellation with low complexity is achieved theoretically. A coding gain of 2.4 dB with 8 dB SNR is obtained by using Monte Carlo simulations. The TCM systems and demodulators were tested under an Additive White Gaussian Noise channel by using Matlab's Simulink block diagrams.
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36

Childs, Robert Daniel. "High speed output interface for a multifrequency quaternary phase shift keying signal generated on an industry standard computer." Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/23250.

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Approved for public release; distribution is unlimited
A multiple frequency quaternary phase shift keyed signal is generated using a complex Fast Fourier Transform on an industry standard personal computer and is output using direct memory access through a digital to analog converter. The output is permitted at rates of up to the maximum direct memory access rate of the computer. An assembly language program loop, direct hardware output, and high level language output are compared as alternate solutions to the problem of outputting a data stream contained in the computer primary memory.
http://archive.org/details/highspeedoutputi00chil
Lieutenant, United States Navy
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37

Feher, Kamilo. "SPECTRAL EFFICIENCY OF COMMERCIAL WIRELESS AND TELEMETRY SYSTEMS IS DOUBLED WITH IRIG 106-00 STANDARDIZED FQPSK AND IS QUADRUPLED WITH FQAM." International Foundation for Telemetering, 2000. http://hdl.handle.net/10150/606757.

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International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California
Advances in spectrally efficient Feher’s Quadrature Phase Shift Keying (FQPSK) and Feher‘s Quadrature Amplitude Modulation (FQAM) patented technologies, commercial and government “dual-use” FQPSK products and Test & Evaluation (T&E) results are highlighted in this overview paper. US and international customer requirements/systems, programs and recent deployments and standardization programs are also described. FQPSK doubles the spectral efficiency of PCM/FM Telemetry and of Feher patented Gaussian Minimum Shift Keying (GMSK or FGMSK) and of alternatives, while FQAM quadruples the spectral efficiency of these systems. The predominant focus of this presentation is on an overview and advances of IRIG 106-00 standardized FQPSK technologies. FQAM systems will also be described. Use of FQPSK for applications such as telemetry, data links, clear mode, TDMA ,CSMA and CDMA, OCDMA, WCDMA as well as OFDM – COFDM will be included in the presentation.
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38

Al-Sharari, Hamed. "An implementation of acquisition using transform domain/cycle code shift keying system on a multipath channel." Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1177004799.

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39

Martin, Warren L. "FQPSK DEVELOPMENTS RECOMMENDED FOR CCSDS STANDARDIZATION BY NASA JPL." International Foundation for Telemetering, 2000. http://hdl.handle.net/10150/607720.

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International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California
In 1992, international space agencies became concerned that increasing frequency band congestion, together with attempts by the mobile telephone industry to obtain additional bandwidth, would result in substantially more interference incidents. The CCSDS undertook a technical study to identify and recommend more bandwidth efficient modulation schemes, which would permit more users to co-exist in a frequency band while reducing interference incidents. This paper describes the contribution of the Jet Propulsion Laboratory (JPL) to that effort.
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40

Lee, Dennis, Marvin Simon, and Tsun-Yee Yan. "ENHANCED PERFORMANCE OF FQPSK-B RECEIVER BASED ON TRELLIS-CODED VITERBI DEMODULATION." International Foundation for Telemetering, 2000. http://hdl.handle.net/10150/607724.

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International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California
Commercial FQPSK-B receivers traditionally use symbol-by-symbol detection and have a 2 dB Eb=No loss relative to ideal QPSK at a bit error rate (BER) of 10^(-5). An enhanced FQPSK-B receiver using a Viterbi algorithm (VA) to perform trellis decoding is simulated and shown to have a 1.2 dB Eb=No improvement over symbol-by-symbol detection for 10^(-5)5 BER at the cost of increased complexity. A simplified Viterbi receiver with a reduced trellis and significantly less complexity is introduced with only a slight BER degradation compared to the full Viterbi receiver. In addition, a theoretical bit error probability expression for the symbol-by-symbol FQPSK-B receiver is derived and compared with simulation results.
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41

Agarwal, Shweta S. "QUADRATURE PHASE SHIFT KEYING-DIRECT SEQUENCE SPREAD SPECTRUM-CODE DIVISION MULTIPLE ACCESS WITH DISPARATE QUADRATURE CHIP AND DATA RATES." Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1134508354.

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42

Shaw, Christopher. "Adjacent Channel Interference for Turbo-Coded APSK." International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606238.

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ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California
A study of the effects of interference caused by adjacent channels on the performance of turbo-coded 16- and 32-APSK. Included in our discussion is the spectral regrowth in the nonlinear power amplifier when driven by a non-constant envelope modulation. Ultimately, we present a set of channel spacing guidelines when using turbo-coded APSK for aeronautical telemetry.
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43

Moon, Todd K., and Chet Lo. "Bandwidth Efficient Signaling Using Multiscale Wavelet Functions and its Performance in a Rician Fast Fading Channel Employing Differential Detection." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/608755.

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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada
In this paper, orthogonal wavelets are employed to produce multiscale signaling. It is shown that signaling using these functions is bandwidth efficient compared other signaling schemes, including SFSK and GMSK. For signaling in Rician fast fading channel, it is also shown that scaling functions is superior in term of achieving low level of probability of error. Even for multiscale signaling, the level probability of error achieved by using wavelet is lower than conventional flat-top signaling. The benefits are largest for channels with small B(D)T , in which the degradation due to fading is most severe.
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44

Gao, Wei, Shih-Ho Wang, and Kamilo Feher. "TESTS AND EVALUATIONS OF ADAPTIVE FEHER EQUALIZERS FOR A LARGE CLASS OF SYSTEMS, INCLUDING FQPSK." International Foundation for Telemetering, 2000. http://hdl.handle.net/10150/606772.

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International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California
Design and performance evaluation of a low-complexity equalizer for recently standardized spectral efficient Feher patented quadrature phase shift keying (FQPSK) system [1] over multipath fading channel is presented. The implementation based on a Feher patented equalizer (FE) [1] is of a structure with three branches, which are individually used to compensate for a moving fade notch with different locations. These branches are switched by the control signal that is generated based on pseudo-error on-line detection technique. It is demonstrated that for typical aeronautical telemetry RF frequency selective fading channels, having delay spreads in 20 – 200 ns range, the adaptive FE reduces the number of statistical outages by more than 60% without the need for training bits and without increasing the receiver synchronization time.
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45

Lee, Tong-Fu, Shih-Ho Wang, Chia-Liang Liu, and Liu Bao. "FQPSK-L: An Improved Constant Envelope Modulation Scheme for QPSK." International Foundation for Telemetering, 1998. http://hdl.handle.net/10150/609210.

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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California
A new constant envelope modulation scheme and architecture for QPSK by cubic spline interpolation methods which increase spectral efficiency and power efficiency, named FQPSK-L, is presented. This modulation technique is an extension of the Feher Quadrature Shift Keying (FQPSK) patented technologies, see Ref [1]. Being a constant envelope modulation, FQPSK-L can operate with class C power amplifier without spectrum regrowth. We achieve a more compact spectrum with comparable bit error rate performance. For example, FQPSK-L is about 20% more spectral efficient than GMSK BTb=0.3 from 40 to 70 dB attenuation point. Moreover, FQPSK-L intrinsically has spikes at fc ± 0.5fb, fc ± 1.0fb, fc ± 1.5fb, ... which are useful for carrier recovery, symbol time recovery and fading compensation. In Rayleigh fading channel, FQPSK-L outperform GMSK BTb=0.3 by 0.8 dB. FQPSK-L is an excellent scheme for wireless and satellite communications which require high spectral and power efficiency.
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46

Othman, Rami. "Study of reception techniques for aeronautical telemetry modulations." Thesis, CentraleSupélec, 2019. http://www.theses.fr/2019CSUP0012.

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La télémesure aéronautique est un système utilisé pendant la phase des essais en vol qui consiste à transmettre en temps-réel les données mesurées à bord de l'avion vers une station sol par le biais d'une liaison radiofréquence. Elle est une opération critique visant à surveiller le comportement de l’avion et à garantir la sécurité du pilote. La conception et les performances des émetteurs et des récepteurs ont été améliorées au fil des années mais tout en gardant la même famille de modulation utilisée pour transmettre les données. Ces données sont modulées par une modulation à phase continue (CPM) car cette dernière possède une enveloppe complexe constante, ce qui permet l’emploi des amplificateurs de puissance dans leur régime de saturation sans distordre le signal. Cependant, contrairement aux modulations classiques, la modulation CPM n’est pas une fonction linéaire des symboles transmis, ce qui rend la tâche de la démodulation complexe surtout quand on considère des scenarii assez compliqués tels que la présence des multi trajets ou bien l’emploi d’un système multi-antennes. Dans cette thèse, on se focalise sur une modulation appelée « Shaped Offset Quadrature Phase Shift Keying telemetry group » (SOQPSK-TG) qui commence à être de plus en plus populaire en télémesure aéronautique. Cette modulation appartient à une famille particulière de CPM car elle transmet des symboles ternaires au lieu de binaires. Dans ce travail, nous développons différents algorithmes de réception pour cette modulation en considérant différents scenarii afin de garantir un lien de télémesure permanent. Les solutions proposées offrent des performances attrayantes tout en gardant une complexité raisonnable pour une implémentation en temps-réel
Aeronautical telemetry is a system used during the flight testing phase to monitor the behaviour of the plane by transmitting in real-time the aircraft dynamics from the aircraft to the ground station over a radio-frequency link. It is a critical process that requires highly reliable systems to ensure the pilot's safety. The design and the performance of the transmitting/ receiving equipment have been progressively upgraded over the years, and they mainly rely on continuous phase modulations (CPM) to convey the data. CPM is transmitter friendly because it has a constant complex envelope and therefore power amplifiers can be used at their saturation mode without distorting the signal. However, due to the nonlinear nature of this modulation, it can make the demodulation a hard task especially when considering complex scenarios such as the presence of multipath or the use of multiple antenna transmitters. In this PhD thesis, we focus on shaped offset quadrature phase-shift keying telemetry group (SOQPSK-TG) whose use is getting more and more popular in aeronautical. This modulation belongs to a particular CPM family since it transmits ternary symbols instead of binary ones. In this work, several reception algorithms have been developed for this modulation under different scenarios to ensure the availability of aeronautical telemetry link. These solutions offer excellent power efficiency without prohibitive complexity
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47

Horcher, Gregg. "DESIGN CONSIDERATIONS FOR DEVELOPMENT OF AN AIRBORNE FQPSK TRANSMITTER." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/607301.

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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada
This paper describes the design considerations used by Aydin Telemetry in the development of its high data rate Feher Patented Quadrature Phase Shift Keying (FQPSK) [1] frequency agile transmitter. We will address several key areas of interest to the Telemetry community, such as the use of commercially available VLSI parts to minimize parts count while maximizing reliability, adaptive filtering to accommodate a wide range of data rates, and user selectable features to achieve a universal transmitter design. User selectable features include differential encoder, 15 stage IRIG randomizer, and 1/2 rate convolutional FEC coding. This paper also addresses the spectral efficiency that can be achieved using a Class-C amplifier with FQPSK and the measured bit error rate (BER) performance versus Eb/No.
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48

Feher, Kamilo, Robert Jefferis, and Eugene Law. "Spectral Efficiency and Adjacent Channel Interference Performance Definitions and Requirements for Telemetry Applications." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/607340.

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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada
Organizations such as the National Telecommunications and Information Administration (NTIA), Federal Communications Commission (FCC), International Telecommunications Union (ITU) and various commercial entities use a wide range of spectral efficiency criteria in different broadcast and wireless system applications. These criteria and related specifications have significant differences. This paper briefly reviews some common adjacent channel interference (ACI) definitions as well as issues surrounding the definition of spectral efficiency. The impact of these parameters on system bit error rate (BER) performance and closely "packed" adjacent signals is described. ACI criteria and spectral efficiency definitions considered appropriate for existing telemetry applications and deployment of new generations of spectrally efficient systems are illustrated. Specific ACI and spectral efficiency performance requirements adopted by the Department of Defense (DoD) and Advanced Range Telemetry (ARTM) project are highlighted.
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49

Lee, Tong-Fu, Shih-Ho Wang, and Chia-Liang Liu. "FQPSK-O: An Improved Performance Constant Envelope Modulation Scheme for OQPSK." International Foundation for Telemetering, 1998. http://hdl.handle.net/10150/607387.

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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California
A new constant envelope modulation scheme for OQPSK, called FQPSK-O, is presented. This modulation technique is an extension of the Feher Quadrature Shift Keying (FQPSK) patented technologies, see Ref[l]. This scheme uses cubic spline interpolation to generate very smooth baseband waveforms in order to increase the spectral and power efficiency. Being a constant envelope modulation, FQPSK-O can operate with class C power amplifier without spectrum regrowth. We achieve a more compact spectrum with comparable bit error rate performance. For example, the spectrum of FQPSK-O is 25% narrower than that of GMSK with BT(b)=0.3 and FQPSK-1 with hardlimiter [2] at -40 dB attenuation point. For coherent demodulation under AWGN channel, FQPSK-O has almost the same BER performance as FQPSK-1 with hardlimiter. Both of them are better than GMSK with BT(b)=0.3 for BER < 10^-4. In Rayleigh fading channel, FQPSK-O outperforms GMSK with BT(b)=0.3 by 2 dB. FQPSK-O is an excellent scheme for wireless and satellite communications which require high spectral and power efficiency.
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50

Temple, Kip. "MODULATOR IMBALANCE EFFECTS ON THE FQPSK AIRBORNE TELEMETRY LINK." International Foundation for Telemetering, 2000. http://hdl.handle.net/10150/607721.

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International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California
When designing transmitters for quadrature modulation schemes, the designer always tries to achieve good balance and symmetry of the in-phase (I) and quadrature (Q) branches of the modulator in terms of amplitude, phase, and offsets. Perfect balance between modulators is ideal but rarely if ever achieved. The Advance Range Telemetry (ARTM) program has placed indirect specifications on the remnant carrier and sideband levels which are controlled by modulator imbalance. These specifications will govern the ARTM programs first generation of Feher’s patented quadrature phase shift keying, version B (FQPSK-B) [9] airborne telemetry transmitters. The ARTM Program has also adopted test procedures for quantifying these modulation imbalances. This paper looks at the effects of modulator imbalances on spectral occupancy and bit error probability of the airborne telemetry link. It also outlines how these imbalances influence the levels in one of the ARTM specifications. Recommendations are presented based on the measured data for higher bit rate telemetry systems.
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