A General Guide for Communication System Engineers to Improve QoS (Published)
The Quality of Service (QoS) is one of most important issues in providing an acceptable level of service. Communication engineers need a guide for action to improve QoS parameters such as data rate, bit error rate, latency, and jitter. Improving QoS includes a set of steps that should be performed by an engineer; these steps are belonging to two categories, system and network steps. In this paper we developed a flow chart of a general guide to improve QoS in a digital communication system, based on our knowledge of the modern communication system and impairments that lead to system degradation. We outline the options and advices to approach the subject of QoS in digital transmission.
Keywords: Data Rate, Delay, Jitter., QOS, bit error rate
Effect of Non-Optimal Amplitude Frequency Response on Transmission of Power Line Communication Signals (Published)
Power line Communication (PLC) systems represent a relatively recent and rapidly evolving technology, aimed at the utilization of the electricity power lines for the transmission of data. This is due to increasing demand of low cost telecommunication, broadband and access to internet services. Power lines are inherently the most attractive medium for home networking due to its universal existence in homes, the abundance of alternating current outlets and the simplicity of the power plug. This work presented the effect of non-optimal amplitude frequency on transmission of power line communication signals by utilizing Orthogonal Frequency Division Multiplexing (OFDM) system. The simulation was carried out using MATLAB/SIMULINK with additive white Gaussian noise (AWGN) in order to obtain correct simulation performance results. Two channels of PLC were considered, the worse channel was taken into account and the channel output signal power was obtained. Bit Error Rate (BER) of Binary Phase Shift Keying (BPSK) in conjunction with multipath channel was used for a comparative performance of the studies. The results indicated that data transmission in PLC environment needed a signal to be amplified or transmitted at higher powers. The result also showed that non-optimal amplitude frequency response had no effect on transmission of the PLC signal in the frequency bands despite the low noise signal in the system. The result demonstrated that OFDM exhibited better BER performance for providing adequate transmission channel for information over a PLC system. This approach provided accurate reliability, security and robustness for better management of available energy resources to overcome the limitations of existing Power line communication technology.
Keywords: Gaussian noise, binary phase shift keying, bit error rate, orthogonal frequency division multiplexing, power line communication, transmission line
