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Introduction/purpose: The paper presents the theory and the design issues of a transceiver for a discrete-time cosine pulse transmission. The operation of the transceiver and all signals are analyzed in both time and frequency domains. Methods: The detailed theoretical models of the transmitter and the receiver are presented based on their block schematics expressed in terms of mathematical operators. The transceiver blocks are simulated and the results of their simulation are presented and compared with the theoretical results. Results: Discrete-time signals at the input and the output of each transceiver block are derived in the mathematical form and presented in the time and frequency domain. A transceiver simulator is developed in Matlab. The simulation results confirmed the theoretical findings. Conclusion: The results of this work contribute to the theoretical modeling and design of modern transceivers that can be used for discrete-time cosine pulse transmission. [ABSTRACT FROM AUTHOR]

Introduction/purpose: The paper presents the theory and design issues of a discrete-time communication system used for discrete-time pulse transmission with and without filtering. Signals are analyzed in both the time domain and the frequency domain. Methods: The system is theoretically analyzed using block schematics expressed in terms of mathematic operators and the system simulation is performed to confirm the theoretical findings. Results: Discrete-time signals are presented in the time domain and the frequency domain as well as confirmed by a simulation designed in Matlab. Conclusion: The results of the paper contribute to the theoretical modeling and design of modern discrete communication systems. [ABSTRACT FROM AUTHOR]

Abstract: A new approach to teaching Communication Systems course is proposed, which is based on the use of animations as a complement to the lecture material. The animations are designed to visualize abstract mathematical concepts, related to modulation techniques and communication system analysis in presence of noise, and present these concepts to the students in visual and understandable form in the classroom. The animations have double purpose. They are to be used, firstly, by the lecturers during lecture presentations, and secondly, as an additional aid to the students to support their self‐learning activity. The animations are developed on MATLAB platform. [ABSTRACT FROM AUTHOR]

SUMMARY Binary spreading sequences or chaotic nonbinary sequences are used in code division multiple access systems. In contrast to those sequences, this paper presents the theory, simulation, and implementation in digital signal processor technology of a code division multiple access system that uses random spreading sequences. The expressions for probability of bit error are derived for the cases when the additive white Gaussian noise and fading are present in the channel. Because the overall transmitted signal is a sum of random signals, the security of signal transmission in this communication system can be enormously increased and will depend on the goodness of the random sequence generator. The developed theory was confirmed by a prototype of the system that was designed in digital signal processor technology. The prototype used spreading sequences that had statistical characteristics very close to the characteristics of theoretical random sequences. The main problem in the system is how to synchronize the received spread sequence with the locally generated sequence. Hence, a mathematical model of the synchronization block for the system has been separately designed and developed. The synchronization procedure has been demonstrated on the basis of application of a periodically repeated pilot sequence. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]