Aspects of the properties, enumeration and construction of points on diagonal and Hermitian hypersurfaces have been considered extensively in the literature and are further considered here. The zeta function of diagonal hypersurfaces is... more
Aspects of the properties, enumeration and construction of points on diagonal and Hermitian hypersurfaces have been considered extensively in the literature and are further considered here. The zeta function of diagonal hypersurfaces is given as a direct result of the work of Wolfmann. Recursive construction techniques for the set of rational points of Hermitian hypersurfaces are of interest. The relationship of these techniques here to the construction of codes on hypersurfaces is briefly noted.
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The authors describe and analyze a model for the Gaussian multiple access channel, where the addition of new users is governed by a renewal process. An information-theoretic approach is used to find the set of transmission rates at which... more
The authors describe and analyze a model for the Gaussian multiple access channel, where the addition of new users is governed by a renewal process. An information-theoretic approach is used to find the set of transmission rates at which the reliable communication of the messages of each user is possible. The capacity for the Markovian multiple access channel is shown
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This paper examines the gains to be realized by using an errors-and-erasures decoding strategy on a pulse jammed channel, rather than errors-only, for concatenated Reed-Solomon/orthogonal codes. The work is largely computational and... more
This paper examines the gains to be realized by using an errors-and-erasures decoding strategy on a pulse jammed channel, rather than errors-only, for concatenated Reed-Solomon/orthogonal codes. The work is largely computational and serves to quantify the gains achievable in such a situation. Previous studies have shown that the gains of errors-and-erasures over errors-only on the AWGN channel are minimal. The
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The performance of Reed-Solomon (RS) error-correcting codes with slow frequency hopped (SFH) differential phase shift keying (DPSK) signaling is analyzed and evaluated under worst-case partial-band noise (PBN) and worst-case multitone... more
The performance of Reed-Solomon (RS) error-correcting codes with slow frequency hopped (SFH) differential phase shift keying (DPSK) signaling is analyzed and evaluated under worst-case partial-band noise (PBN) and worst-case multitone (MT) jamming. The results of a study of the bit error rate (BER) performance of this coded system are presented. A representative set of the performance curves is shown. SFH is used because the differential signaling required only the phase of the previous received signal as a reference. Using DPSK eliminates the need to establish a phase reference for the hop, as with coherent signaling. From the results it is clear that the number of codeword symbols per hop must be small in order for the RS code to provide protection against jamming. Otherwise, no improvement over uncoded DPSK is gained. Lowering the symbols per hop can be achieved either by reducing the number of bits per hop, or interleaving the RS codewords to a depth determined by the hop length and RS code parameters.
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Research Interests: Computer Science, Distributed Computing, Privacy, Government, Computer Networks, and 12 moreCryptography, Anonymity, Global Positioning System, Computer Network, Public key cryptography, Scalability, Distributed Computing Systems, Public Key Encryption, Coarse Grained Soil, Diffie-Hellman-DSA, Public Key, and Network Time Protocol
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The use of curves in algebraic geometries, in applications such as coding and cryptography, has now an extensive literature and has been responsible for dra-matic developments in both subjects. In coding theory, the use of modular curves... more
The use of curves in algebraic geometries, in applications such as coding and cryptography, has now an extensive literature and has been responsible for dra-matic developments in both subjects. In coding theory, the use of modular curves to construct asymptotically good ...
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... Zhenhui Tan and IF Blake Department of Electrical and Computer Engineering University of Waterloo Waterloo, Ontario, Canada N2L 3G1 ... The output of the fre-quency de-hopper in the receiver is given by K L ~r 1 2 ak(t - %,I)... more
... Zhenhui Tan and IF Blake Department of Electrical and Computer Engineering University of Waterloo Waterloo, Ontario, Canada N2L 3G1 ... The output of the fre-quency de-hopper in the receiver is given by K L ~r 1 2 ak(t - %,I) Cos{z*[fc + bk(t - %,l)wt + @k,l(t)} -k a(t) (5) ...
Research Interests: Computer Science, Communication System, Wireless, Spread Spectrum, Fading, and 10 moreDegradation, Rayleigh fading, Spread Spectrum Communication, Demodulation, Direct Sequence Spread Spectrum Cdma, Phase Modulation, Frequency shift keying, Hybrid System, Multipath Propagation, and Phase shift keying
Research Interests: Computer Science, Distributed Computing, Routing protocols, Modulation, Optimization, and 15 moreBit Error Rate, Rayleigh fading, BER, Resource Management, asymptotic Analysis, Power allocation, Interference, RELAY, Gaussian noise, Signal to Noise Ratio, Geometric Programming, Spatial Diversity, Electrical And Electronic Engineering, Cooperative Diversity, and Relay Channel
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Research Interests: Mathematics, Applied Mathematics, Stochastic Process, Computer Science, Propulsion, and 11 moreEstimation Theory, Stochastic processes, Least squares estimation, Density Functional Theory, Estimation, Random Processes, Random Variables, Characteristic Function, Hilbert Space, Electrical And Electronic Engineering, and Univariate Analysis
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Research Interests: Probability Theory, Computer Science, Distributed Computing, Adaptive Control, Fading Channel, and 15 moreAdaptive Signal Processing, Spread Spectrum, Feedback, Fading, Coherence, Minimum shift keying, Lagrange Multiplier, Rayleigh Scattering, Jamming, Bandwidth, Electrical And Electronic Engineering, Frequency shift keying, Fading channels, Awgn, and Additive White Gaussian Noise
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We introduce a new digital signature model, called conditionally verifiable signature (CVS), which allows a signer to specify and convince a recipient under what conditions his signature would become valid and verifiable; the resulting... more
We introduce a new digital signature model, called conditionally verifiable signature (CVS), which allows a signer to specify and convince a recipient under what conditions his signature would become valid and verifiable; the resulting signature is not publicly ...
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... [l] EF Assmus, Jr., J.-M. Goethals, and HF Mattson, Jr., Generalized t-designs and maioritv decoding of linear codes, Information and Control, Vol. 32, pp. 43-60, i976: - [2] M. Rahman and Ian F. Blake, Majority logic decoding... more
... [l] EF Assmus, Jr., J.-M. Goethals, and HF Mattson, Jr., Generalized t-designs and maioritv decoding of linear codes, Information and Control, Vol. 32, pp. 43-60, i976: - [2] M. Rahman and Ian F. Blake, Majority logic decoding using combinatorial designs, IEEE Trans. Inform. ...
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The performance of diversity and/or coding is evaluated for FH/MFSK signaling over Rayleigh fading channels in the presence of jamming. The effects of partial-band tone and partial-band noise jamming on uncoded and coded systems are... more
The performance of diversity and/or coding is evaluated for FH/MFSK signaling over Rayleigh fading channels in the presence of jamming. The effects of partial-band tone and partial-band noise jamming on uncoded and coded systems are considered. The results indicate that FH/MFSK signaling with diversity provides satisfactory performance for jammed fading channels. For coded FH/MFSK signaling over fading channels, noise jamming may be more effective than tone jamming. The amount of improvement resulting from the use of diversity in conjunction with coding depends upon many factors, including the nature of the channel, the degree of channel state information available at the decoder, the type of decoding, and the modulation alphabet size.