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Practical network-based techniques for mobile positioning in UMTS

EURASIP JOURNAL ON APPLIED SIGNAL PROCESSING 2006年第1期2006卷 012930-012930页

作者： Borkowski, Jakub Lempiainen, Jukka Tampere Univ Technol Inst Commun Engn FIN-33101 Tampere Finland

This paper presents results of research on network-based positioning for UMTS ( universal mobile telecommunication system). Two new applicable network-based cellular location methods are proposed and assessed by field measurements and simulations. The obtained results indicate that estimation of the position at a sufficient accuracy for most of the location-based services does not have to involve significant changes in the terminals and in the network infrastructure. In particular, regular UMTS terminals can be used in the presented PCM ( pilot correlation method), while the other proposed method - the ECID+RTT ( cell identification + round trip time) requires only minor software updates in the network and user equipment. The performed field measurements of the PCM reveal that in an urban network, 67% of users can be located with an accuracy of 70 m. In turn, simulations of the ECID+RTT report accuracy of 60 m - 100 m for 67% of the location estimates in an urban scenario.

关键词： Mobile positioning Device Terminal field measure pulse code modulation Location based services Cellular communications user facility

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IMPROVED DIGITAL HYDRAULIC TRACKING CONTROL OF WATER HYDRAULIC CYLINDER DRIVE

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INTERNATIONAL JOURNAL OF FLUID POWER 2005年第1期6卷 29-39页

作者： Linjama, Matti Vilenius, Matti Tampere Univ Technol Inst Hydraul & Automat POB 589 FIN-33010 Tampere Finland

A position tracking control system is implemented by utilizing parallel-connected on/off valve series. The pulse code modulation method is used to achieve stepwise flow control and four valve series, each having four two-way solenoid valves, are used. A cost function based controller is used to control simultaneously and independently flow paths from supply to cylinder chambers and from chambers to tank. It is shown that controllability can be improved especially at low velocities by allowing three or four valve series to be open simultaneously instead of using classical inflow-outflow control.

关键词： pulse code modulation on/off control tracking control

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Modified pulse repetition coding boosting energy detector performance in low data rate systems

Modified pulse repetition coding boosting energy detector pe...

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IEEE International Conference on Ultra-Wideband

作者： Troesch, F Althaus, F Wittneben, A Swiss Fed Inst Technol Commun Technol Lab CH-8092 Zurich Switzerland

ISBN: (纸本)078039397X

We consider Ultra-Wideband Impulse Radio (UWB-IR) Low Data Rate (LDR) applications where a more complex Cluster Head (CH) communicates with many basic Sensors Nodes (SN). At receiver side, noncoherent Energy Detectors (ED) operating at low sampling clock, i.e., below 300kHz, are focused. Drawback is that EDs suffer from significant performance losses with respect to coherent receivers. pulse Repetition Coding (PRC) is a known solution to increase receiver performance at the expense of more transmit power. But in LDR systems known PRC is very inefficient due to the low receiver sampling clock. Boosting transmit power is not possible due to Federal Communications Commission's (FCC) power constraints. Hence, we present a modified PRC scheme solving this problem. Modified Repetition coded Binary pulse Position modulation (MPRC-BPPM) fully exploits FCC power constraints and for EDs of fixed integration duration is optimal with respect to Bit Error Rate (BER). Furthermore, MPRC-BPPM combined with ED outperforms SRAKE receivers at the expense of more transmit power and makes ED's performance robust against strong channel delay spread variations.

关键词： binary codes data communication error statistics modulation coding pulse code modulation radio receivers ultra wideband communication BER Federal Communications Commission bit error rate cluster head low data rate systems modified pulse repetition coding Federal Communications Commission (FCC) cluster head Ultra wideband communication modulation coding binary code radio receivers data communication Low Data Rate repetition coding energy detector

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Design and development of PCM decommutator with PCI-interface

Design and development of PCM decommutator with PCI-interfac...

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24th DASC: 24th Digital Avionics Systems Conference

作者： Palanivelu, S. Shanmugam, J. Division of Avionics Madras Institute of Technology Chrompet Chennai India

ISBN: (纸本)0780393074

PCM Decommutator is the important subsystem at the ground station in telemetry. The existing system of decommutator is designed using discrete components for each function of decommutation, hence there is a need to design decommutator using VHDL to make it compact by implementing it in FPGA. A PCM decommutator is designed with PCI Interface using VHDL. The Hardware Design consists of three major modules a) Decommutator b) FIFO and c) PCI Interface management module. Decommutator is designed to decode the individual parameters from the incoming serial PCM stream. FIFO is developed to store the decommutated data temporarily before sending it to PC. The PCI Interface management module is to enable the communication between the FPGA and PCI 9054 thereby to PCI bus. A software program is written in VC to read the data from FPGA and storing it on a PC hard disc. PCI Interface management is tested and verified. The decommutator with FIFO is validated using simulator © 2005 IEEE.

关键词： pulse code modulation

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Multiple-description coding of logarithmic PCM

Multiple-description coding of logarithmic PCM

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13th European Signal Processing Conference, EUSIPCO 2005

作者： Clüver, Kai Sikora, Thomas Communication Systems Group Technische Universität Berlin Einsteinufer 17 10587 Berlin Germany

ISBN: (纸本)1604238216

A practical approach for the design of multiple-description scalar quantization of speech is presented that conforms to standard G.711 PCM. The method chiefly consists of an index assignment algorithm that enables the side decoders to exhibit SNR characteristics comparable to those of the standard logarithmic quantizer. With two-channel transmission of multiple descriptions, an increase in robustness to lossy channels is obtained without violation of the standard coding method. The method found is suitable for the design of multiple descriptions of any given scalar quantizer, e. g. one within a complex speech coder.

关键词： pulse code modulation

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Calibration of 5-hole probe for flow angles from advanced technologies testing aircraft system flight data

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DEFENCE SCIENCE JOURNAL 2004年第2期54卷 111-123页

作者： Parameswaran, V Jategaonkar, RV Natl Aerosp Lab Bangalore 560017 Karnataka India

This paper describes the investigations carried out to calibrate the 5-hole probe for flow angles from advanced technologies testing aircraft system flight data. The flight tests were carried out with gear up and at nominal mid-centre of gravity location for two landing flap positions, delta(f) = IN and 14degrees. Dynamic manoeuvres were executed to excite the short period and Dutch roll mode of the aircraft. In addition, pull up, push down and steady sideslip manoeuvres were also carried out. The data compatibility check on the recorded flight data has been carried out using maximum likelihood output error algorithm to estimate the bias, scale factor, and time delay in the pressure measurements from the 5-hole probe mounted on a noseboom in front of aircraft nose. Through a way of kinematic consistency checking, flight-validated scale factors, biases, and time delays are determined for the differential pressure measurements for both angle of attack and angle of sideslip. Also, the dynamic pressure measurement is found to have time delays. Based on the earlier investigations, it is once again confirmed that the measurements of attitude angles, obtained from the inertial platform, clearly indicate time delays referred to the other signals like linear accelerations and angular rates which are measured with the dedicated flight instrumentation package. The identified time delays in attitude angles agreed well with the inertial platform specifications. The estimates of sensitivity coefficients and scale factors from the flight data analysis correlates reasonably well with the manufacturer Rosemount calibration curves for the tested Mach range 0.23-0.53. The flight data analysis at Mach number of about 0.59 indicate Mach dependency for the angle of attack.

关键词： 5-hole probe parameter estimation method flight data flow angle calibration flight reconstruction technique angle of attack angle of sideslip ATTAS flight data Rosemount 5-hole probe ATTAS test aircraft flight-validated scale factors inertial platform specifications path reconstruction dynamic pressure measurement aerodynamic parameters time delays pulse code modulation longitudnal-and lateral-directional motion analog filters

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A low computational predictor coefficient algorithm for ADPCM implementation of portable recording devices

A low computational predictor coefficient algorithm for ADPC...

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47th Midwest Symposium on Circuits and Systems (MWSCAS 2004)

作者： Boonyakitmaitree, C Nandhasri, K Ngarmnil, J Mahanakorn Univ Technol Dept Elect Engn Bangkok 10530 Thailand

ISBN: (纸本)078038346X

This paper proposes a modification of ADPCM algorithm to be suitable for hardware implementation of portable audio devices. This is accomplished by a simplification of predictor coefficient algorithm which normally requires a high complexity correlation algorithm, while the sound quality measured as SNR remains relatively the same to those of the original ADPCM. The less complicated calculation results in a reduction of the chip area and power consumption, thus it is suitable for pocket solid-state speech and audio recorder. Simulations on MATLAB verify the performances and experimental results on XILINX FPGA synthesis confirming the functionalities and significant reduction of device count by 63% of the implementation by the original algorithm.

关键词： pulse code modulation

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PCM/FM performance enhancement using Reed Solomon channel coding

PCM/FM performance enhancement using Reed Solomon channel co...

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IEEE Aerospace Conference

作者： Taggart, D Kumar, R Wagner, N Krikorian, Y Wang, C Elyashar, N Cutler, M Stevens, C Aerosp Corp Commun Syst Engn Dept El Segundo CA USA

ISBN: (纸本)0780381556

This paper presents analytical and detailed computer simulation results of the performance enhancement of pulse code modulation/Frequency modulation (PCM/FM) links using Reed Solomon (RS) channel coding. PCM/FM is a commonly deployed technique for a wide variety of telemetry and other links. Nevertheless, the required SNR to provide acceptable Bit Error Rate (BER) can be considerable. Thus, it is desired to provide channel coding to reduce the SNR requirement. The simulation of PCM/FM with and without RS coding requires the application of a variety of Signal Processing techniques discussed in the paper.

关键词： pulse code modulation links frequency modulation channel coding Reed-Solomon codes error statistics forward error correction error correction codes Gaussian noise PCM-FM performance enhancement RS channel coding Reed Solomon channel coding computer simulation pulse code modulation telemetry SNR BER bit error rate signal processing techniques digital links communication links random errors symbol rate errors burst error correcting codes FM demodulator click noise

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The MLP Lossless Compression System for PCM Audio

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AES: Journal of the Audio Engineering Society 2004年第3期52卷 243-260页

作者： Gerzon, Michael A. Craven, P.G. Stuart, J.R. Law, Malcolm J. Wilson, Rhonda J. Meridian Audio Ltd. Huntingdon Combs. PE29 6EX United Kingdom Algol Applications Ltd. Steyning West Sussex BN44 3RE United Kingdom

Lossless compression provides bit-exact delivery of the original signal and is ideal where the highest possible confidence in the final sound quality is required. Meridian lossless packing (MLP) was adopted in 1999 as the lossless coding method used on DVD-Audio. MLP uses four principal strategies to reduce both the total quantity and the peak rate of encoded data. MLP can invert a matrix transformation losslessly, this allows a two-channel representation to be transmitted alongside a multichannel signal, with a minimal increase in the data rate. It is illustrated how the characteristics of the incoming audio affect the coding performance, and MLP's versatility, achieved by the use of substreams and an open-ended metadata specification, is demonstrated.

关键词： pulse code modulation

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Adaptive differential pulse-code modulator with nonlinear filter-predictor

Elektrosvyaz

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Elektrosvyaz 2004年第5期 36-38页

作者： Kirillov, S.N. Lotsmanov, A.A.

It is pointed out that it is impossible to apply in the on-line regime the algorithms suggested earlier for optimization of the nonlinear filter-predictor (FP) coefficients of the adaptive differential pulse-code modulation (ADPCM) codecs. It is advantageous to apply the adaptation algorithms (AA) of the nonlinear FP coefficients under the conditions of a priori uncertainty and in locally-stationary speech signals. The AA of the nonlinear nonrecursive FP coefficients of the ADPCM codec were studied in this work.

关键词： pulse code modulation

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