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Providing a pretty adequate environment condition between the transmission and the receiver for a WSN (wireless sensor network), in which deployed sensor nodes and fusion center, is investigated in the paper. Moreover, an algorithm promotes the energy efficient, increases the accuracy of sensing data and prolongs the lifetime of sensor nodes deployed over an WSNs is proposed. On the basis of adopting sensor management, which involves sensor movement sequences, sensor location arrangement, lifetime requirement for sensor nodes deploy surveillance environment, and the data fusion center, are addressed too. Simulation results from the lifetime performance for sensor nodes defeated by parameters about the environment around the WSNs are illustrated. Parameters aforementioned are including sensing distance, path loss factor, number bits of a transmitted packet, and interference suffering from the path of data transmission etc. Furthermore, the algorithm of sensor location arrangement is modified for the purpose of improving the lifetime performance in WSNs environments. In addition, simulation results show that the proposed algorithm in this paper is not only definitely to improve the energy efficient sufficiently, but the sensing accuracy and the lifetime performance of the sensor nodes are also prolonged significantly.

Recently, the advantages of WSNs (wireless sensor network) has fast grown for applying to, such as, military surveillance, health caring, planet monitoring, and a lot of other kinds of relative fields. One of the most important reasons for lasting all the application of WSNs is the support of energy to each sensor nodes distributed in the sensing areas. Therefore, the schemes of concerting for prolonging the lifetime of sensor nodes become remarkable issues to discuss. According to the protocol of IEEE 802.15.4 [

We proposed a scheme of adopting sensors location arrangement for the purpose of improving the lifetime performance of the WSNs scenario in this paper. It is known that the lifetime of every un-pre-located sensor will affect definitely the detection performance for WSNs. So far, there are several researches have been published in discussion the field of WSNs. The problems of dominating the lifetime performance of the sensor nodes in WSNs have been investigated in [

Motivated by the preview work results, In this paper some factors, such as sensing distance, path loss factor, number bits of a transmitted packet, interference suffering from path of data transmission, are involved in the system performance analysis. An environment aware algorithm for promoting the energy efficient, increasing the accuracy of sensing data and prolonging the lifetime of sensor nodes for WSNs is proposed. The paper is organized as follows, the scenario model related to WSNs is described in Section 2. The lifetime performance analysis of WSNs is studied in Section 3. In Section 4 the results and discussion are illustrated. There is a brief conclusion is drawn in Section 5.

It is known that the realizable and the accuracy of sensed data gathered from the algorithm of decentralized processing in WSNs is more believable than that of the centralized processing, and the load of data transportation between each node can be reduced. In the paper a sensor network shown in

introducing to means of fusion among the sensor nodes is necessary. There two means of data fusion are included: 1) maximum number fusion, and 2) majority detection fusion. Basically, the fusion nodes are required to perform event detection based on the maximum measurement number, such that the missing probability, , can be reduced. Consider that there is a maximum number, , selected from n sensed measurements, , which is given as

where is the function of selecting the maximum one element, and the CDF (cumulate distribution function) of the events’ random variable for the selection fact can be written as

where the measured values on each of the nth sensor node are considered independently each other. Hence, after the maximum value has been fused in the fusion center, the missing probability, , of a single sensor node can be calculated as

where represents the hypothesis that when the event happens, represent the probability occurs in each event of fused sensor, and indicated the detection threshold value. By the way, following up operation rule of the detection theory, after the maximum value is fused the detection probability, , and false alarm probability, , can be determined as

respectively. Then, the cost function of detection error probability, , can be given as

where, and are corresponding to express the priori probabilities of event occurring and without occurring. Similarly, in the majority detection fusion, the false alarm probability, , and the missing probability, , can be expressed as

respectively, where the random variable is used to make decision the states of an event occurring or without occurring. Thus, the detection probability, , is given as

and the detection error probability, , can be obtained as

Once the detection probability and the error probability of the individual sensor node, accordingly, the fusion will be held immediately Basis on the condition that there are n events occur really from N sensor nodes, and the total missing probability and the false alarm probability of the local fusion can be correspondingly expressed as

In the paper three reasons are mentioned to analyze the lifetime performance of WSNs, though there are several parameters definitely control the lifetime performance, such as the sensing distance, the sensor numbers, and the fusion algorithm. The much most important reason should be the condition of transmission environments between the sensor node and the fusion center.

For a given event, e.g., the tracking of some targets, and assume that the WSNs is deployed in a squared area of size, the total number of sensor nodes is N, thus denotes the node density which is considered as uniformly distributed in the following discussion. The discrete Poisson distribution can be used to characterize the probability that there are g sensor nodes located within the area around the event [

It should be claimed that the covered area of WSN will be constrained avoiding the results from the simulation becomes divergent. In addition, by combining the previous equation with (6) for the purpose of determining the average detection error probability, , in fusion center, it is obtained as

In the case wherein the probability that any event is detected by at least g times within in sensor nodes can be calculated as

where indicates the sensing range in which a target can be detected, the pdf (probability density function), , of the range counting from any node in WSNs to its gth nearest sensor node can be modeled as

The most concerned event for lifetime performance of WSNs should be the supporting energy which is includeing both the transmission and the receive energies. The lifetime performance can be evaluated by defining how long the sensor node in the whole network to finish the duties involving data sensing and data fusion, that is, with N randomly deployed sensor nodes the sensing lifetime, , should be definitely defined as

where denotes the savable energy of a single sensor node, represents the expectation operator, and the average energy of each sensor can be written as

where is shown in (11), expresses the dissipated energy of a single sensor node, and it can be calculated as

where denotes the exponent path loss [

It is believed that lifetime of the sensor node will be deeply overruled by the length of the transmission bit number, Bit. Additionally, conditions of propagation channel between sensing node and the fusion center are involved in this study. The exponent path loss is considered as the parameter for evaluation the lifetime performance, and the path loss factor is given as [

where is the exponent path loss, then the length of the transmission bit number can be easily obtained as

Furthermore, the fading situation of the wireless communication channel is taken into account the simulation model. The channel fading model is characterized by the Nakagami-m statistical distribution which is the most useful one which is for experimental in accuracy. The severe fading of the channel situation is quantied with the fading figures, m. The larger value of m, the superior of the communication channel is [

Two scenarios in the paper are proposed, one of them is the random arrangement and the other one lines up arrangement of sensor nodes. The one shown in

where. Thereafter, with the assumption described previously that means there are g sensor nodes are selected out from the N sensor nodes, and they can transmit the sensing data to fusion center after the sensing operations sequence of the event is completed. Hereafter, the error probability of detection under the case of that the sensor location arrangement with two lines up can be obtained by some random variables transform, and shown as

where and are both two parameters of the Poisson statistical distribution.

Consider some factors for the lifetime of a sensor node WSNs. For instance, the path loss factor, , of the transmission channel between the sensor node and the fusion center, the bit number, Bit, for transmitting the sensed data to the fusion center, and the sensing range, , etc. The area is considered as square for the numerical results. The number of sensor nodes is assumed as for both the calculation of Figures 3 and 4. The results from comparing with different exponent path loss () are shown in

Moreover, different arrange of sensor nodes is considered in

up arrangement, with 50 sensor nodes are applied. It is valuable to note that the lifetime is prolonged under the condition which arranged the sensor nodes considering of two lines up arrangement. The probability of sensing accuracy vs sensing distance considered under different fading channel is illustrated in

The issue of lifetime performance is analyzed in this paper. The main reasons to promote the energy efficient, increase sensing accuracy and prolong the lifetime of sensor nodes for WSNs (wireless sensor networks) is described. On the basis of adopting sensor management includes sensor movements sequence and sensor location arrangement, we address the issue of lifetime requirement for sensor nodes which deployed in a surveillance nodes and the data fusion center. The numerical results which definitely show that different arrangement methods are not only able to improve the energy efficient sufficiently, but the sensing accuracy and the lifetime of the sensor nodes are also obtained significantly promoted.