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This paper presents a novel design of Very High Frequency RF Amplifier using 180nm CMOS technology. Role of silicon in the semiconductor industry and the necessity of low power RF circuits are discussed. The function of RF amplifier along with its applications and classes are explained. Existing designs of RF amplifiers are analyzed, implemented and simulated. A new architecture with better performance, which can operate at a Very High Frequency of 15.849GHz with meager power dissipation of 0.20mW and with considerable bandwidth of 1.8068GHz, is proposed, analyzed and simulated in Synopsys HSPICE to verify the architecture. Comparison between the existing designs of RF amplifiers and the proposed RF Amplifier is carried out with respect to operating frequency, power dissipation, Bandwidth, supply voltage and Gain which are the critical parameters of RF design.

SummaryRouting protocols in wireless sensor networks (WSNs) typically employ a transmitter-oriented approach in which the next hop node is selected based on neighbor or network information. This approach incurs a large overhead when the accurate neighbor information is needed for efficient and reliable routing. In this paper, a novel receiver-oriented load-balancing and reliable routing (RLRR) protocol is proposed. In RLRR, an intermediate node solicits next hop candidates, each of which is to respond with its own backoff time dubbed a temporal gradient (TG). In this way, the next hop is selected without any central coordination on a packet-by-packet basis. Thus, each node needs not maintain any neighbor information. The remaining energy level used to determine the TG is always accurate and up-to-date. Furthermore, neighbor nodes whose hop count is less than the soliciting node participate in the next-hop selection process with loop-free operation guarantee. Comprehensive simulations are carried out to show that RLRR achieves relatively longer network lifetime and higher reliability than other existing schemes. Copyright

Abstract. The objective of this paper is to analyse state dependent arrival in bulk retrial queueing system with immediate Bernoulli feedback, multiple vacations, threshold and constant retrial policy. Primary customers are arriving into the system in bulk with different arrival rates λ and λ . If arriving customers find the server is busy then the entire batch will join to orbit. Customer from orbit request service one by one with constant retrial rate . On the other hand if an arrival of customers finds the server is idle then customers will be served in batches according to general bulk service rule. After service completion, customers may request service again with probability as feedback or leave from the system with probability 1 − . In the service completion epoch, if the orbit size is zero then the server leaves for multiple vacations. The server continues the vacation until the orbit size reaches the value ' N' ( N > b ). At the vacation completion, if the orbit size is ' N' then the server becomes ready to provide service for customers from the main pool or from the orbit. For the designed queueing model, probability generating function of the queue size at an arbitrary time will be obtained by using supplementary variable technique. Various performance measures will be derived with suitable numerical illustrations.