abstract—in this paper, the problem of secure transmission in two-hop amplify-and-forward (af) systems with an untrusted relay is investigated. to prevent the untrusted relay from intercepting the source message and to achieve positive secrecy rate, the destination-based cooperative jamming (dbcj) technique is used. in this method the destination sends an intended jamming signal to the relay. t...

in order to evaluate the effect of nitrogen absorption and use efficiency in relay intercropping for winter wheat and maize, a field experiment was conducted during 2008-2009 at the agricultural research station of ferdowsi university of mashhad, iran. a randomized block design with three replications was used. treatments included four combinations of relay intercropping of wheat and maize (thr...

This paper presents a novel impedance-based approach for out-of-step (OOS) protection of a synchronous generator. The most popular and commonly used approaches for detecting OOS conditions are based on the measurement of positive sequence impedance at relay location. However, FACTS devices change the measured impedance value and thus disrupt the performance of impedance-based relay function. In...

Polar codes, that have been recently introduced by Arikan, are one of the first codes that achieved the capacity for vast numerous channels and they also have low complexity in symmetric memoryless channels. Polar codes are constructed based on a phenomenon called channel polarization. This paper discusses relay channel polarization in order to achieve the capacity and show that if inputs of tw...

in this paper, an interval approach is presented to achieve perfect selectivity and maximum sensitivity in distance relay zones, considering uncertainties. for this purpose, first, the uncertainties affecting the settings of the three zones of a distance relay are discussed. then, by using the monte-carlo simulation, the uncertainties are modelled and the impedances seen by the distance relay a...

Abstract—In this paper, the problem of secure transmission in two-hop amplify-and-forward (AF) systems with an untrusted relay is investigated. To prevent the untrusted relay from intercepting the source message and to achieve positive secrecy rate, the destination-based cooperative jamming (DBCJ) technique is used. In this method the destination sends an intended jamming signal to the relay. T...

Utility engineers and consultants use relay models to select the relay types suited for a particular application, and to analyze the performance of relays that appear to either operate incorrectly or fail to operate on the occurrence of a fault. Instead of using actual prototypes, manufacturers use relay model designing to expedite and economize the process of developing new relays. Electric po...

In this paper, we study the Diversity-Multiplexing Tradeoff (DMT) of the Decode or Quantize and Forward (DoQF) protocol recently proposed in [1] for the half duplex single relay channel. Our results show that this static relaying protocol achieves the 2 by 1 MISO bound for multiplexing gains r < 0.25. The DMT of the classical non orthogonal Decode and Forward (DF) protocol is also derived. We s...

Cooperative relay communication is a promising means of wireless communication in which cooperation is used to create a virtual transmit array between the source and the destination, thereby providing the much-needed diversity to combat the fading channel. Consider a communication system in which there are a total of N + 1 nodes that cooperate in the communication between source node S and dest...

In this manuscript, we propose a design method of digital filters which cancel coupling waves generated in single-frequency full-duplex wireless relay stations by using the sampled-data H∞ control theory. Simulation results show effectiveness of the proposed method to communication performance from a base station to a terminal.