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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.
371

The impact of interferometric noise on the performance of optical communication networks

Legg, Peter Jonathon January 1995 (has links)
Interferometric noise, arising on the interference of data and parasitic crosstalk and common to many current and proposed fibre optic communication networks, may induce unacceptable power penalties and bit-error-rate floors. This work addresses key aspects of this problem via experiment and theoretical analysis: the origin and characteristics of the noise, the resultant performance degradation of optical networks, and solution paths. The study of a single crosstalk interferer generates a classification of all interferometric noise forms and reveals the key properties of probability density function and power spectrum. Performance degradation from theory and experiment agree closely. The aggregation of multiple crosstalk terms is analysed and the validity of Gaussian statistics, predicted by the Central Limit Theorem, is demonstrated. It is predicted that the total crosstalk level of noise generating terms should be held below -25 dB for a penalty of less than I dB - a further 2 to 4 dB may lead to network failure. Optical TDM switching networks, constructed from discrete lithium niobate directional couplers of -15 dB isolation, and delay lines, illustrate the importance of interferometric noise. Larger networks are modelled on a computer simulator (XFlatch) that tracks all crosstalk waveforms, calculates both interferometric and amplifier noise, and thus the bit-error-rate. A bilateral approach is proposed to manage interferometric noise; crosstalk power is minimised and noise owing to the residual crosstalk is RF rejected. Several methods are critically discussed. A novel technique, exploiting intra-bit frequency evolution of directly modulated DFB lasers in response to injection heating, is introduced and critically assessed.
372

Speech analysis by digital computer

Smith, B. D. V. January 1979 (has links)
No description available.
373

Development, computer implementation and application of Bond Graph theory

White, B. A. January 1975 (has links)
No description available.
374

Empirical and theoretical methods of BER prediction in binary FSK communication systems subjected to impulsive noise

Turkmani, A. M. D. January 1985 (has links)
No description available.
375

A computational approach to meta-knowledge : calculating breadth and salience

Rau, Lisa F. January 1992 (has links)
No description available.
376

Digital frequency modulation : full and partial response signalling techniques

Murthy, M. S. January 1982 (has links)
No description available.
377

Integration of neural and stochastic modelling techniques for speech recognition

Zhao, Z. January 1992 (has links)
No description available.
378

Constant envelope modulation coding

Redwood-Sawyerr, J. A. S. January 1985 (has links)
No description available.
379

A cochlear model for processing of speech signals, which exhibits nonlinearity, masking and adaptation

Dhanda, Mungal Singh January 1992 (has links)
No description available.
380

Intermodulation studies for single-channel-per-carrier satellite communication systems

Ganem, H. January 1981 (has links)
No description available.

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