Thesis (M.S.)--Ohio University, March, 1982. / Title from PDF t.p.

International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / This paper introduces a PPK intelligent demodulator used in the PCM--PPK (pulse position keying) telemetry system. It describes the basic requirement of the system for the PPK signal demodulator and analyses the insufficiancy of the full-hardware PPK demodulator. It also advances a PPK demodulating scheme based on the TMS32020 digital signal processor and a block diagram of the demodulator, states the method of detecting frame synchronization, analyses the precision of sync-building and gives the way of calculating the miss and error probability of frame sync. The result makes it clear that the demodulator based on TMS32020 has programmable feature for the bit rate and frame synchronization and realizes easily the system demand of the separate demodulating of output signals of the multi-channel receiver and then the synthesis processing of the realtime data.

This thesis covers the scope of one out of many ways to diagnose gearboxes, demodulating the excited vibrational signals to enhance fault detection and identification. The topic is not only of academic interest since the achievements that can be made by successful machine condition monitoring in the industry. It has a potential value that is close to be absurd, for example unplanned production stops is commonly known to be one of the worst nightmares for manufacturing companies and if one can detect faults in early stages one can improve the possibilityto plan a production stop and therefore increase the profit. Four demodulation algorithms were developed and implemented in MATLAB on data characterized by close to stationarity and distinctive energy centered around the harmonics of the gearmesh frequency. The resulting algorithms for narrowband phase and amplitude demodulation was shown to outperform Hilbert transform based phase and amplitude demodulation algorithms in gearbox diagnostics. One of the goals with the thesis was therefore reached; demodulation algorithms were developed and implemented on data. A comparison of these algorithms was done and a conclusion of which demodulation technique is superior was done. Experimental work was carried out on a test-rig and both local and distributed faults were introduced to two gearboxes, one kind of fault per gearbox. However, the data acquired from the test-rig showed severe non-stationarity and smeared spectrum properties even when angular resampling was performed and therefore a major drawback of the demodulation techniques was exploited since the methods for demodulation in this thesis are not applicable for signals with smeared spectrums. The other goal was therefore not accomplished; to distinguish a local fault from a distributed fault in data acquired by experimental work by applying the selected demodulation techniques.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 66-67). Also available via the Internet.

Thesis (M.E. 1976) from the Department of Electrical Engineering, University of Adelaide.

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Much modem telemetry is transmitted in a digital format and to be compatible with existing range equipment the digital data is impressed on the carrier using FM modulation. The receiving system in common use employs an FM limiter/discriminator as a detector followed by an integrate and dump matched filter for bit detection. This system has been studied by previous authors [1] and it is well known that in the absence of frequency uncertainty the optimum transmission parameters consist of a modulation index of .7 (peak-to-peak deviation divided by the bit rate) and an IF filter bandwidth equal to the bit rate followed by a limiter discriminator. In many cases, there is a need for some small amount of analog telemetry transmission in addition to the digital data discussed above. In these cases it is common practice to include analog subcarriers on the main carrier with the digital data modulating the carrier at baseband, the resulting system is called PCM/FM + FM/FM. These hybrid analog/digital systems are the subject of this paper. In particular this paper addresses the performance of these systems through simulation using the Block Oriented System Simulator (BOSS) from Comdisco and with analytical techniques to obtain the BER versus SNR curves for these systems. The simulation is used over a wide range of parameters to find the optimum values of modulation index and IF bandwidth for these systems.

An interferometer is used for phase detection. Thus, the hydrophone which is based on interferometric optic fiber sensor has extremely high sensitivity. Sagnac interferometric hydrophone has low noise of marine environment, which is more suitably used to detect underwater acoustic signal than that of a Mach-Zehnder interferometer. In this paper, a configuration of dual Sagnac interferometer was proposed. The mathematical model was derived and analyzed. The fiber optic sensor head contains mandrel type and planar one. The acoustic window are made of silicon rubbers. It was should that we can increase their sensitivities by increase number of wrapping fiber coils. In our experiment, the result shows that among all the mandrel sensor heads, the most highest dynamic range is up to 37.6¡Ó1.4 dB, and its sensitivity is -223.3¡Ó1.7 dB re V/1µPa ; while the dynamic range of the planar sensor head is 42.1¡Ó1.5 dB, and its sensitivity is -213.8¡Ó1.3 dB re V/1µPa¡C As for the configuration of the optical interferometers, the intensity of the dual Sagnac interferometer is 20 dB larger than its Sagnac counterpart. Its dynamic range is above 66 dB, which is 24 dB larger than that of the Sagnac interferometer with the sensitivity of -192.0 dB re V/1µPa. In addition, by using software simulation to design optimal lengths of delay fibers , we can increase interferometer¡¦s the dynamic range of underwater acoustic detection. This paper verify that, by means of adjusting the length of these two delay fibers, we can actually increase the dynamic range of acoustic signal detection.

No description available.

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 / This design adopts the software radio and DBPSK（Differential Binary Phase Shift Keying）modulation-demodulation, which detects the telecommand receiving by the guided-missile system correctly. The DBPSK modulation module in Altera FPGA chip converts the binary telecommand into DBPSK signal, which will be frequency modulated after D/A conversion. In the receiver, the FM signal is demodulated and A/D converted before sending to the FPGA. The DBPSK demodulation module in FPGA finally gets the telecommand which will be tally with the telecommand from transmitter. At last, the whole DBPSK modulation-demodulation module is embedded into the remote control test system. The design is working properly and meeting the requirements of the test system.

ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / The concept of a range area network dedicated to the reception of telemetry from airborne test articles is explored. The range area network consists of ground-based radios that receive telemetry packets from an airborne test article and relay those packets through the network to a data sink (e.g., the main telemetry display and processing center). The network may use either "dumb" nodes or "smart" nodes and this choice presents a trade-off involving node complexity, network bandwidth, and required RF power. Using a somewhat idealized, but nonetheless realistic example at the Edwards AFB complex and link budgets based on the emerging iNET standard, we show that a network consisting of just 6 nodes reduces the L-band airborne transmitter power to 6W and the ground-based transmitters to 3W. If the airborne transmitter is restricted to 1W at L-band, then coverage can be provided by a grid of 50 nodes.