We have studied the performance of a distributed medium access control (MAC) scheme in an OFDM based powerline communication (PLC) network. Most of the existing approaches for MAC in PLC networks consider a centralized means of allocating carriers to voice and data calls. We present a distributed approach for carrier allocation where the access units choose a carrier from the set of available c...

This paper deals with carrier synchronization problem in coherent communication system, such as BPSK and QPSK. First, this paper surveys and analyzes currently existing carrier synchronization algorithms and relevant receiver structures. After an analysis of those methods, a novel algorithm called feedback compensation is proposed, including the receiver structures based on this new synchroniza...

In this paper, we implement the robust demodulator for mobile broadband satellite internet access systems. Especially, in order to achieve the good synchronization under very low SNR, a large frequency offset, and Doppler frequency offset with constraints of mobile satellite communication, we introduce the efficient carrier freq. offset estimating algorithm and the carrier phase estimating algo...

The increase of the capacity of communication systems can be achieved by an increase in the channel bit-rate. Increasing the channel rate assumes the utilization of shorter carrier pulses. It is well known that the propagation of short pulses is strongly affected by the fibre dispersion, which results in large temporal broadening of the carrier pulses. Subsequently, the carrier pulse power spre...

In presenting this thesis in partial fulfillment of the requirements for a Postgraduate degree from the University of Saskatchewan, the author agrees that the Libraries of this University may make it freely available for inspection. The author further agree that permission for copying of this thesis in any manner, in whole or in part, for scholarly purposes may be granted by the professor who s...

With the goal of decreasing the interference at sub-carrier level, the allocation of sub-carrier frequencies in an OFDMA based system is selective. This selective allocation can be seen like a permutation of a frequency “sequence”. This paper proposes a new analyzing tool for the frequencies permutation used in WiMAX mobile communications: the distances spectrum (DS). This tool can offer a mean...

Radio spectrum is the most valuable resource for wireless communication, thus high spectrum utilization is mostly desired to increase system economy. With an efficient frequency allocation method and an effective handoff procedure, a personal communication system can be operated with minimal number of carriers while maintaining an acceptable level of system performance, and thereby leading to a...

Orthogonal Frequency Division Multiplexing (OFDM) systems are very sensitive to carrier frequency offset (CFO), caused by either frequency differences between transmitter and receiver local oscillators or by frequency selective channels. The CFO disturbs the orthogonality among subcarriers of OFDM system and results intercarrier interference (ICI), which degrades the bit error rate (BER) perfor...

In this article we propose majority pseudo-noise sequence (PNS) acquisition method for multi-carrier direct sequence code division multiple access (MC-DS-CDMA) communication systems, that allows for low hardware requirements and able to operate in low-quality channels. We research this method using specially developеd Simulink model. The proposed method may find application in military and publ...

Current-mode-logic circuits play an important role in the design of CMOS frequency synthesizers for modern wireless digital communication systems. They provide the building blocks for frequency dividers with input frequencies in the range of the desired carrier frequencies. In this communication we estimate the upper limit frequency as a function of the gate length using voltage swing considera...