Publications

Gerber, R & Braun, R 1998, New Connections Telecommunications in a Changing South Africa, University of Cape Town Press (ZA).
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Written for students as well as business managers in telecommunications industries, this book investigates the telecommunications sector worldwide, and includes a detailed study of the South African perspective.

Abry, P & Veitch, D 1998, 'Wavelet analysis of long-range-dependent traffic', Information Theory, IEEE Transactions on, vol. 44, pp. 2-15.

Abry, P, Veitch, D & Flandrin, P 1998, 'Long-range Dependence: Revisiting Aggregation with Wavelets', Journal of Time Series Analysis, vol. 19, pp. 253-266.

Aslund, M, Canning, J & Bazylenko, M 1998, 'High-temperature stable gratings in germanosilicate planar waveguides', OPTICS LETTERS, vol. 23, no. 24, pp. 1898-1900.
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Auzanneau, F & Ziolkowski, RW 1998, 'Microwave signal rectification using artificial composite materials composed of diode-loaded electrically small dipole antennas', IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, vol. 46, no. 11, pp. 1628-1637.
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Auzanneau, F & Ziolkowski, RW 1998, 'Theoretical study of synthetic bianisotropic materials', JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS, vol. 12, no. 3, pp. 353-370.
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Bazylenko, MV, Moss, D & Canning, J 1998, 'Complex photosensitivity observed in germanosilica planar waveguides', OPTICS LETTERS, vol. 23, no. 9, pp. 697-699.
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Butchart, K & Braun, RM 1998, 'An adaptive modulation scheme for low earth orbit satellites', PROCEEDINGS OF THE 1998 SOUTH AFRICAN SYMPOSIUM ON COMMUNICATIONS AND SIGNAL PROCESSING, pp. 43-46.
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Canning, J & Moss, D 1998, 'Grating-based transmission bandpass filters using dispersion-matched mode conversion', OPTICS LETTERS, vol. 23, no. 3, pp. 174-176.
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Canning, J, Moss, D, Aslund, M & Bazylenko, M 1998, 'Negative index gratings in germanosilicate planar waveguides', ELECTRONICS LETTERS, vol. 34, no. 4, pp. 366-367.
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Cucchiara, R, Neri, G & Piccardi, M 1998, 'A Real-time Hardware Implementation Of The Hough Transform', Journal Of Systems Architecture, vol. 45, no. 1, pp. 31-45.
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The paper presents a hardware implementation of algorithms based on the Hough transform (HT) for real-time straight line detection. In particular, the basic HT on the edge points (EHT) and the Gradient-Weighted Hough transform (GWHT) for gray-level image

Cuthbert, J & Braun, RM 1998, 'Selection Of Multi-h Modulation Sets Using A Stochastic Search Algorithm', IEE Proceedings-communications, vol. 145, no. 1, pp. 41-46.
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Multi-h CPFSK modulation is simple to implement, spectrally efficient, and has inherent error correction properties. Multi-h requires large parameter sets to obtain high coding gain. Large numbers of combinations may need to be investigated. A fast effic

Dvorak, SL, Ziolkowski, RW & Felsen, LB 1998, 'Hybrid analytical-numerical approach for modeling transient wave propagation in Lorentz media', JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION, vol. 15, no. 5, pp. 1241-1255.
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He, S, Hintz, TB & Szewcow, U 1998, 'Replicated Shared Object Model For Edge Detection With Spiral Architecture', Parallel And Distributed Processing, vol. 1388, pp. 252-260.
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Edge detection in computer vision and image processing is a process which detects one kind of significant features appearing as discontinuities in intensities. A parallel edge detection algorithm based on Spiral Architeture is designed in this paper by a

He, S, Hintz, TB & Szewcow, U 1998, 'Replicated Shared Object Model For Parallel Edge Detection Algorithm Based On Spiral Architecture', Future Generation Computer Systems, vol. 14, no. 5-6, pp. 341-350.
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Edge detection in computer vision and image processing is a process which detects one kind of significant feature in an image that appears as discontinuities in intensities. A parallel edge detection algorithm based on spiral architecture is designed in

HILDING, JAIM & VEITCH, D 1998, 'UNDERSTANDING END-TO-END INTERNET TRAFFIC DYNAMICS.', GLOBECOM..., pp. 1118-1118.

HILDING, JAIM & VEITCH, D 1998, 'UNDERSTANDING END-TO-END INTERNET TRAFFIC DYNAMICS.', GLOBECOM..., pp. 1118-1118.

Liang, T & Ziolkowski, RW 1998, 'Dispersion effects on grating-assisted output couplers under ultrafast pulse excitations', MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, vol. 17, no. 1, pp. 17-23.
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Liang, T & Ziolkowski, RW 1998, 'Grating assisted waveguide-to-waveguide couplers', IEEE PHOTONICS TECHNOLOGY LETTERS, vol. 10, no. 5, pp. 693-695.
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Liang, T & Ziolkowski, RW 1998, 'Grating assisted waveguide-to-waveguide couplers', IEEE Photonics Technology Letters, vol. 10, no. 3, pp. 693-695.
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A new radiation-type waveguide-to-waveguide coupler is proposed. The coupling is realized through gratings embedded on the dielectric waveguides involved. Compared to the conventional hybrid-mode coupler, this type of coupler has advantages in that the two waveguides can be quite dissimilar as well as being separated by large distances. It is demonstrated that the coupling performance of this radiation-type coupler can be enhanced significantly by using photonic bandgap (PBG) structures.

Liang, T & Ziolkowski, RW 1998, 'Ultrafast pulsed mode effects on the performance of grating-assisted output couplers of finite extent', OPTICS LETTERS, vol. 23, no. 6, pp. 469-471.
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Oughstun, KE & Ziolkowski, RW 1998, 'Mathematics and modeling in modern optics', JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION, vol. 15, no. 5, pp. 1238-1238.
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Saban, D & Braun, RM 1998, 'Multi-carrier direct sequence CDMA in fading situations', PROCEEDINGS OF THE 1998 SOUTH AFRICAN SYMPOSIUM ON COMMUNICATIONS AND SIGNAL PROCESSING, pp. 33-38.
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Saban, G & Braun, RM 1998, 'Wireless local loop and packet radio technology for developing communities', PROCEEDINGS OF THE 1998 SOUTH AFRICAN SYMPOSIUM ON COMMUNICATIONS AND SIGNAL PROCESSING, pp. 1-6.
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Seaman, B & Braun, RM 1998, 'Using cyclostationarity in the modulation classification of analogue signals', PROCEEDINGS OF THE 1998 SOUTH AFRICAN SYMPOSIUM ON COMMUNICATIONS AND SIGNAL PROCESSING, pp. 261-266.
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Tellambura, C, Guo, YJ & Barton, SK 1998, 'Channel estimation using aperiodic binary sequences', IEEE Communications Letters, vol. 2, no. 5, pp. 140-142.
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Estimating a channel impulse response using a known aperiodic sequence is considered. The problem can be reduced to minimizing the trace of the inverse of a Toeplitz matrix. An efficient algorithm for computing this trace is developed and optimal binary sequences up to length 32 are found and tabulated. The use of complementary sequences in this context is also investigated. It is shown that the eigenvalues of the autocorrelation matrices of a pair of complementary sequences sum to a known constant.

Ziolkowski, RW & Gogny, DM 1998, 'Cavity modifications of nuclear internal conversion rates – abstract', Journal of Electromagnetic Waves and Applications, vol. 12, no. 5, pp. 675-676.
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We extend the principles of cavity quantum electrodynamics to nuclei inside low-loss cavities. The resulting nucleus-cavity system exhibits spontaneous emission and internal conversion rates which differ radically from those of the individual components. The quantum mechanical derivations of these rates are given. The internal conversion process occurs via the exchange of a virtual photon between an excited nucleus and an electron bound to that nucleus. Even though the photon is virtual, partial suppression of the internal conversion process is shown to be theoretically possible. With a controlled modification of the internal conversion rate using a high- Q cavity, one can achieve a number of potentially interesting applications including an excited nuclear state containment unit, a nuclear battery, and a neutron detector. © Journal of Electromagnetic Waves and Applications. All rights reserved.

Andren, J, Hilding, M & Veitch, D 1998, 'Understanding end-to-end internet traffic dynamics', Global Telecommunications Conference, 1998. GLOBECOM 1998. The Bridge to Global Integration. IEEE, IEEE, pp. 1118-1122.

Banh, BAJ, Anido, GJ & Dutkiewicz, E 1998, 'Handover re-routing schemes for connection oriented services in mobile ATM networks', Proceedings - IEEE INFOCOM, pp. 1139-1146.
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Wireless ATM (WATM) will be used to support broadband applications for future generation mobile services. To achieve this, the existing ATM protocol must be augmented with mobility management capabilities. One of the important components of mobility management is the ability of the network to seamlessly re-route existing connections to different parts of the network. To date, a number of schemes have been proposed for broadband wireless networks. These schemes can potentially be used in WATM networks. In this paper, we compare the performance of these schemes in terms of their complexity, handover latency, communication disruption period and buffer and bandwidth requirements.

Barattin, M, Cucchiara, R & Piccardi, M 1998, 'A Rule-based Vehicular Traffic Tracking System', Proceedings of the Joint Conference on Information Sciences, pp. 334-337.
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The paper presents a computer vision-based approach to the problem of vehicular traffic monitoring. The approach associates a high-level tracking system to a low-level system that performs moving vehicles detection. The high-level module is based on a large set of rules and is able to keep tracks of all moving or stopped vehicles along the image sequence.

Canning, J, Sceats, MG & Carter, ALG 1997, 'UV-induced structural changes in photosensitive optical fibres', JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS, International Workshop on Structure and Functional Optical Properties of Silica and Silica-Related Glasses, JAPAN SOC APPLIED PHYSICS, TOYOTA MOTOR CORP, MIKKABI CREAT CTR, SHIZUOKA, JAPAN, pp. 59-61.
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Cucchiara, R & Piccardi, M 1998, 'Exploiting image processing locality in cache pre-fetching', FIFTH INTERNATIONAL CONFERENCE ON HIGH PERFORMANCE COMPUTING, PROCEEDINGS, 5th International Conference on High Performance Computing, IEEE COMPUTER SOC, CHENNAI, INDIA, pp. 466-472.
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Guo, YJ, Vadgama, S, Davies, M, Khalab, J, Zarri, M & Spink, D 1998, 'Adaptive antenna for CDMA', IEEE International Symposium on Spread Spectrum Techniques & Applications, pp. 590-594.
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A decision directed adaptive antenna array for the uplink of CDMA cellular systems, which is based on a normalized least mean square algorithm (NLMS), is presented. The bit error ratio performance of the adaptive antenna in various scenarios, which include the use of transmission power control (TPC) and diversity combining, is studied. It is shown that the adaptive antenna outperforms the steering beam technique when the signal-to-noise ratio is large and the active users are clustered. However, the performance of the adaptive antenna becomes very similar to that of the steering beam when there are a large number of randomly distributed active users in the sector.

Liu, RP, Richards, A & Rogers, G 1998, 'MARSHNet, a superimposed QoS guaranteed Virtual Path Network', GLOBECOM 98: IEEE GLOBECOM 1998 - CONFERENCE RECORD, VOLS 1-6, IEEE Global Telecommunications Conference (GLOBECOM 98), IEEE, SYDNEY, AUSTRALIA, pp. 7-12.

Moss, D, Canning, J & Bazylenko, M 1998, 'Bragg gratings in hollow-cathode PECVD germanosilica planar waveguides', Conference on Lasers and Electro-Optics Europe - Technical Digest, p. 425.
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Waveguide gratings were fabricated in intrinsically low-loss (0.2 dB/cm with no annealing) germanosilica waveguide layers without the use of any material presensitization. The waveguides were grown by a novel technique called hollow-cathode PECVD.

Roughan, M, Veitch, D & Abry, P 1998, 'On-line estimation of the parameters of long-range dependence', GLOBECOM 98: IEEE GLOBECOM 1998 - CONFERENCE RECORD, VOLS 1-6, IEEE Global Telecommunications Conference (GLOBECOM 98), IEEE, SYDNEY, AUSTRALIA, pp. 3716-3721.

Roughan, M, Veitch, D & Rumsewicz, M 1998, 'Computing queue-length distributions for power-law queues', INFOCOM’98. Seventeenth Annual Joint Conference of the IEEE Computer and Communications Societies. Proceedings. IEEE, IEEE, pp. 356-363.

Stepanov, DY, Canning, J & Brodzeli, Z 1998, 'High-resolution measurements of fibre Bragg grating transmission spectra', 24TH EUROPEAN CONFERENCE ON OPTICAL COMMUNICATION, VOL 1-3, 24th European Conference on Optical Communications, TELEFONICA ESPANA SA, MADRID, SPAIN, pp. 407-408.

Tellambura, C, Parker, MG & Barton, SK 1998, 'Channel estimation using discrete Fourier transform techniques', GLOBECOM 98: IEEE GLOBECOM 1998 - CONFERENCE RECORD, VOLS 1-6, IEEE Global Telecommunications Conference (GLOBECOM 98), IEEE, SYDNEY, AUSTRALIA, pp. 148-152.

von Bibra, ML, Canning, J & Roberts, A 1997, 'Mode profile modification of H+ ion beam irradiated waveguides using UV processing', JOURNAL OF NON-CRYSTALLINE SOLIDS, Glass and Optical Materials Division / Bragg Gratings, Photosensitivity and Poling in Glass Fibers and Waveguides - Applications and Fundamentals Meeting, ELSEVIER SCIENCE BV, WILLIAMSBURG, VIRGINIA, pp. 121-125.
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Ziolkowski, RW 1998, 'Finite photonic band gap material based waveguides, power splitters and switches', IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4, IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network, IEEE, ATLANTA, GA, pp. 873-873.