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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

Optimal Detection and Estimation for Echo Ranging in a Randomly Fading Environment

Mark, Jon Wei 03 1900 (has links)
<p> A self-synchronized echo ranging system with optimum utilization of signal estimation and detection strategies has been designed and simulated. A binary convolution code has been utilized to modulate the transmitter signal. The random medium is modelled by a vector sum of a fixed and a random component; the medium fading process has a Rician distribution density. A channel estimator has been derived using a maximum a posteriori probability criterion. The estimator is an adaptive processor whereby the variance of the medium fading process is recomputed during each updating cycle. The estimator attempts to provide a coherent input to the correlator. An optimum processor for the signalling described is an ordered serial estimator-correlator combination. It is conjectured that the estimator offers an improvement in signal processing gain of approximately 5 dB over and above the non-optimized system. Accompanying this is an improvement in peak-to -sidelobe ratio and in false alarm probability. A 3 bit (8 level) quantized system is conjectured to be a 'good' trade-off between degradation in system performance and simplification in system implementation.</p> / Thesis / Master of Engineering (MEngr)
2

A Survays On Fading Channel Over West - Java Area for Flight Test Radio Telemetering Purposes

Soelaiman, Adi Dharma, Pudjiastuti, Rina 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1988 / Riviera Hotel, Las Vegas, Nevada / This paper discusses one approach to determine a characteristic of West - Java's air and ground segment as a block-box to accomodate radio waves propagation, especially in L-band ranges, by evaluating both the topographical data and radio reception pattern as measured from ground based telemetry receiving-end system. All the measured signals are random and assumed to be stationair and ergodic. In order to characterize the channel for polarization diversity reception, some statistical analysis are applied to the signal strength measured of both - RHCP and LHCP components of 1531 MHz propagated waves as transmitted fr om NC212-200 PK-NZJ-aircraft. Some computer calculated correlograms of measured data are shown herewith, it is focused for a certain radio corridor at radial 265E relative to the ground based receiving antenna. More over some curves of predicted multipath gain factor are also presented to gain more theoretical back ground. When this paper is written, a further field experiments on the matter concerned is beeing conducted.

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