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The prime necessity in communication system is utilizing the available bandwidth efficiently. Hence, compression of data to be sent over the link has become inevitable. In this paper, an algorithm for compressing hyperspectral space images based on ZigZag 3D-DCT (Discrete Cosine Transform) technique is proposed. This method converts 2D gray-scale images into a 3 dimensional cube formation of 8*8*8 pixels and is operated with DCT. Thereafter the quantization and zig-zag scanning processes are implemented. After completing the processes, the 1D data vector formed facilitates in achieving better compression using run-length coding. Also, in order to design a complete practical system, a suitable irregular LDPC encoder is implemented in order to mitigate losses present in communication link. The performance of the algorithm is verified by plotting various quality measurement graphs, and determining its dominance over standard JPEG.

Since 2005, Smart Grid technology has revolutionized the electric power system industry. Researchers have shown a lot of interest in the opportunities offered by ICT (Information and Communication Technologies), to modernize the operation of electrical networks. This is possible by decarbonizing them as well as monitoring and controlling them with sophisticated communication standards. For this purpose, merging the technologies offered by electrical and telecommunication sector is very crucial. Various wireless communication standards viz. WiMAX, ZigBee, Bluetooth, Wi-Fi, GSM, GPRS, UMTS etc. can be exploited to develop Smart Grid Network and extend communication throughout the distributed system. This paper gives a detailed comparative study of communication protocols that can be implemented in this domain. It focuses on various aspects such as network spanning, data rates, power consumption, data security and encryption standards, data access and spread spectrum techniques, modulation and duplexing schemes for all the communication standards in Smart Grid. Hence by addressing all the critical issues, this paper provides a contemporary look in the still open research areas in Smart Grid Communication.

Incorporation of wireless technology in Automation system has led to the development of remote monitoring and controlling of loads. It is essential to select and implement an appropriate technology according to the desired application area. This paper describes the various factors viz. network topology, network span and transmission time, which influence the performance of the system. It also illustrates ZigBee (over IEEE 802.15.4) based Home Automation system (HAS), for remote controlling and monitoring of loads/appliances. In order to estimate the total power consumption of the desired load, the designed HAS can be operated in either of the two modes viz. Energy measurement IC 'CS5490' based mode and Current sensor IC 'WCS 2705' based mode. It provides real time power monitoring with the help of a PC-based GUI application developed on Net Beans Java platform. Further, the paper emphasizes on performance evaluation of the system by analyzing the various performance metrics viz. the Latency, Round Trip Delay (RTD) time and Received Signal Strength Indicator (RSSI).