Convergecast communication is used in many sensor applications .The flow of data in convergecast routing is from many to one i.e. many sensory nodes sense the data and send through parent child relation to the root node or sink node. Convergecast routing is always followed by broadcasting. In broadcast communication is from one to many and in convergecast it is from many to one. As sensor nodes have limited battery capacity main focus is to save energy. As compare to wired network wireless network is prone to attacks and it is less reliable than the wired network. This paper investigates the affect of header length of network layer on the BER, SNIR, backoff duration, SNR and latency of convergecast routing with the help of omnet++ simulator.

This paper presents a highly efficient modified output combining 3-stage Doherty Power Amplifier (DPA) design using low power LDMOS transistor for Band 40, TD-LTE Micro eNodeB. In this design, modified output combining technique has been used in the output section which meets the output power requirements of Micro eNodeB which cannot be achieved by conventional 3-stage DPA. The modified DPA design achieves 65.3% power added efficiency (PAE) at 39 dBm average output power with 20 MHz LTE signal using 15 watt LDMOS Transistor. 3-stage modified output combining technique increases the linear output power by 1.1 dB and increases the Gain flatness versus power level. The use of Digital Pre-Distortion (DPD) along with modified 3-stage DPA design achieves the linearity requirements as per the 3GPP specifications. The modified DPA combining technique has provided potential economical solution by using low power LDMOS transistor with an advantage of high efficiency.

This paper presents the effect of rician factors in satellite communications with Maximum A Posteriori (MAP) demodulation. Conventional QAM presently in use where the high capacity signaling scheme is required, is characterized with high errors due to the Doppler Effect and the nature of the channel as the order of modulation increases in rician fading channel. MAP detection scheme was used to reduce the error and maximize the probability of choosing correctly at the output of the QAM demodulator. MAP QAM was used as a signaling technique and obtained by taking the logarithm of Likelihood Ratio of observed binary data of an observation random variable at both the Inphase and Quadrature channels. System model was developed around MAP-QAM demodulator over rician factors of 5, 10, and 15 at 90 km/h. System model was simulated and evaluated using Bit Error Rate (BER) to determine the performances of the MAP-MQAM and conventional MQAM for comparison at modulation order 'M' of 4 and 16. The results obtained showed that as the rician factor increases, the BER values decreased indicating better performance with both MAP-MQAM and QAM signaling scheme.

Wireless Sensor Network (WSN) is a self-configuring and highly flexible distributed network used for real time monitoring and is comprised of a number of wireless, minute, battery-operated independent sensor nodes connected to a common sink. Due to energy considerations, the network is generally divided into clusters and the entire communication is carried out through the cluster heads. The clock mismatch between various nodes and clusters often leads to collisions, delay and data loss. In order to overcome this problem, a novel RTS/CTS based Relative Time Synchronization Protocol is being proposed for Radio-Frequency Identification based WSN. It achieves better performance due to its energy efficiency and lower service messages. Simulation results show a substantial improvement in the net throughput and reliability of the network when compared with the GPS-based Synchronization technique.

Power in any cellular network is a key degree of freedom in management of connectivity, energy factors, speed etc. In LTE network the power consumption is dominated by Evolve Node by significant amount of power, to compute this issue a mechanism has been proposed to reduce the power consumption. The power consumption issue is tackle by Discontinuous Transmission (DTX) mechanism where the evolve node is switch off for specified amount of time when there is no occurrence of packet. These are simulated with busty traffic condition which is considered to poison traffic with exponential distribution for delay sensitive and insensitive traffic, where power consumption and latency average is calibrated.

Wireless body area networks (WBANs) are emerging as one of the newest forms of Wireless Sensor Networks. In WBANs, sensor nodes accumulate human physiological data and transmit it to the sink node. However, transmission of physiological data to the sink node over a mobile route becomes a very daunting task for sensors due to their limited battery power. Moreover, replacement of critical sensor nodes is a major challenge in such scenarios. In order to increase network lifetime, some routing protocols have been proposed in the literature, but the majority of them are focused on coverage distance and residual energy of sensor nodes. In this work, we will propose an energy efficient routing algorithm for WBANs that will take into consideration two additional attributes (node criticality and communication count) along with the above stated attributes. These four parameters in the proposed algorithm will result in enhancement of working lifetime of the network via less energy consumption in comparison to existing routing protocols.