Jishun Li

EBRP: An Energy-Efficient and Buffer-Aware Routing Protocol for Mobile Crowdsensing Network

Data collection with high efficiency is a key problem for the completion of crowdsensing tasks in Mobile Crowdsensing Networks. Much work has been done on the opportunistic routing problem, but they usually just focused on the sociality of node, and the attributes of node itself have always been ignored, such as energy and buffer, which are particularly important for the persistent crowdsensing tasks. In this paper, we now modify the spectral clustering algorithm and propose a novel and more practical routing protocol for MCSN, named EBRP, in which the sociality of node and the dynamic changes of the attributes of node itself are all fully considered when the relay nodes are selected. To evaluate the performance of our routing protocol, we have done extensive simulations and much analysis based on three real-life mobility traces. The results show that our EBRP can greatly outperform the existing protocols in terms of delivery ratio, cost, and node survival ratio.

An Energy Supply System for Wireless Sensor Network Nodes

The power source is a critical obstacle for wireless sensor network nodes. In order to prolong the lifetime of wireless sensor networks, this paper presents an energy supply system that uses a specially designed broadband piezoelectric energy harvesting technology for sustaining the operation of wireless sensor network nodes. The proposed energy supply circuit can apply an optimal control voltage to the piezoelectric element to ensure impedance matching between the vibration source and the energy supply system in nonresonance frequencies. As compared to the conventional piezoelectric energy harvesting circuit, it is shown that the efficiency has been increased 4 times. In this work, the overall system structure, the function modules design, and the performance testing analysis are illuminated in detail. Experimental results reveal that this energy supply system can significantly improve power within the wide bands by the active piezoelectric energy harvesting technology and enable wireless sensor network nodes to operate normally.

An Efficient Data Collection Protocol Based on Multihop Routing and Single-Node Cooperation in Wireless Sensor Networks

Considering the constrained resource and energy in wireless sensor networks, an efficient data collection protocol named ESCDD which adopts the multihop routing technology and the single-node selection cooperative communication is proposed to make the communication protocol more simple and easy to realize for the large-scale multihop wireless sensor networks. ESCDD uses the greedy strategy and the control information based on RTS/CTS to select forwarding nodes. Then, the hops in the multihop data transmission are reduced. Based on the power control in physical layer and the control frame called CoTS in MAC layer, ESCDD chooses a single cooperative node to perform cooperative transmission. The receiving node adopts maximal ratio combining (MRC) to recover original data. The energy consumption per hop is reduced. Furthermore, the total energy consumption in data collection process is shared by more nodes and the network lifetime is extended. Compared with GeRaF, EERNFS, and REEFG protocol, the simulation results show that ESCDD can effectively reduce the average delay of multihop data transmission, improve the successful delivery rate of data packets, significantly save the energy consumption of network nodes, and make the energy consumption more balanced.

A Joint Channel Selection and Routing Protocol for Cognitive Radio Network

In cognitive radio network, the activities of primary users will cause great influence on the stability of multiple hops routes between cognitive users. In this regard, a joint channel selection and routing protocol, termed as CSRP, is proposed to ensure route stability and reduce route latency between cognitive users. The channel availability based on historical information and the channel switching delay are used as the channel selection criteria to choose the end-to-end shortest route which possesses high data delivery probabilities and low delays. Besides, simulation results show that the proposed protocol has a better performance in terms of packet transmission delay and data delivery rate compared with the routing protocols based on delay (TDRP) and based on joint routing and channel allocation (PUB-JRCA).

A multi attribute decision routing for load-balancing in crowd sensing network

The emerging crowd sensing network (CSN) can complete the large-scale and complicated sensing tasks by utilizing the collaboration among nodes consciously or unconsciously, which has great significance in practical application. However, the mobility of the nodes leads to intermittent network connectivity, which makes the efficient data delivery become more challenging. Routing design is regarded as an efficient way to deal with this problem, and many schemes have been proposed for such kind of network environments, especially for the complicated sensing tasks in CSN. As for the existing routing schemes, the vast majority of them choose the nodes with higher utility values as relay nodes to forward packets, which can easily cause the load extremely imbalance among nodes. In this paper, we regard the action of relay node selection as a multi attribute decision making problem. Combined with a duplicate optimally stopping strategy, a novel multi attribute decision routing for load-balancing, named MADR-LB, is proposed, which can not only reduce the load of the whole network, but also balance the load of each participating node. Extensive simulations based on four real-life mobility traces and a TVCM model have been done to evaluate the performance of our proposed protocol compared with other existing protocols. The results show that, our proposed protocol can greatly balance the load of nodes and improve the fairness of the nodes while ensuring the overall delivery performance of the network.