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—In a multi-hop wireless sensor network (WSN), the traffic load is not evenly distributed over the nodes. For example, the sensors which are one hop away from the sink relay the whole network traffic. This imbalanced traffic distribution can degrade the network lifetime and functionality. Here, an analysis is proposed to characterize the traffic load(More)
In event-driven wireless sensor networks, the network lifetime has a random nature due to the randomness of data reporting. The lifetime is even more nondeterministic when sensors are also deployed randomly. The lifetime of such a network is influenced by node deployment, initial energy of sensors, packet generation model and the number of sensors. This(More)
Considering event-driven clustered wireless sensor networks, a probabilistic approach for analyzing the network lifetime is presented when events occur randomly over the network field. To this end, we first model the packet transmission rate of the sensors, using the theory of coverage processes and Voronoi tessellation. Then, the probability of achieving a(More)
Clustering sensors is considered as an efficient way for increasing the lifetime of a wireless sensor network. One of the main advantages of these networks, leading to a longer lifetime, is the ability of data aggregation by the cluster head (CH). Assuming a fixed-shape for the cluster, the probability of achieving a desired lifetime by the cluster has been(More)
In wireless sensor networks data, which get generated, is not always same; some data may be more important than others and having different priorities. As deployment sizes and data rates grow, congestion becomes a major problem in these networks. The congestion results in arbitrary dropping of data packets that reduce the overall network throughput. In this(More)
Wireless sensor networks are widely used in security monitoring applications to sense and report specific activities in a field. In path coverage, for example, the network is in charge of monitoring a path and discovering any intruder trying to cross it. In this paper, we investigate the path coverage properties of a randomly deployed wireless sensor(More)
In this paper, we study the effect of users' transmission ordering on the common rate and sum rate of pairwise multiway relay channels (MWRCs) with functional-decode-forward strategy. To this end, we first develop a graphical model for the data transmission in a pairwise MWRC. Using this model, we then find the optimal orderings that achieve the maximum(More)
—Multiple-input multiple-output (MIMO) channels have been studied from various aspects including the average of the mutual information between the transmitter and receiver (er-godic capacity) when the channel gains are known to the receiver only. A common approach for capacity analysis is to find the moment generating function (MGF) of the mutual(More)