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Mobile sensor networks (MSN) in the city environment have dynamic topology and large amounts of data. In order to overcome the problem of data uploading and exchange, data uploading and exchange algorithm (DUEA) is proposed. In DUEA, the three-tier network architecture composed of vehicle nodes, relay nodes and sink nodes is considered. The link estimator, routing engine, and forwarding engine are modified based on CTP (collection tree protocol). In the link estimator, beacon packet is simplified. In the routing engine, the numbers of elements in the send queue of neighbor nodes, and link quality are weighed. The new calculation formulae of ETX value and selection method of father node are proposed. In the forwarding engine, different snooping methods are used for two types of data named general data and warning data. Simulation results show that compared with CTP, DUEA increases data throughput and transmission rate and reduces energy consumption of packet transmission when data is uploaded. DUEA also reduces average transmission delay when data is exchanged. Physical test results show that DUEA achieves desired effect in the testbed. DUEA is effective and feasible and outperforms CTP in the city traffic environment.

In the wireless sensor network, many applications need to known the location of the node, so node location technology is key technology and research hot spot in WSN. Although the trilateral measuring method which has been given just need to know the coordinate of three beacon nodes, and the distance between beacon nodes and unknown nodes, then you can calculate the unknown nodes' coordinates, But in the practical application, due to measurement errors, makes the distance between unknown nodes and three beacon nodes be not accurate, causing there is no solution in the equations of problem. Therefore, this article will introduce the centroid location algorithm thought into the trilateral measuring method, improve the trilateral measurement method, and put forward the trilateral centroid localization algorithm. By calculating the intersection of the intersected round and the center in the area of intersection to estimate unknown nodes, making the unknown nodes coordinates estimated is more accurate.

Mobile ad hoc network is a hotspot in the wireless networks researching domain, and the routing protocol, which is as the core technology on network layers, is particularly important. By analyzing the working mechanism and key techniques of the Ad Hoc routing models, this paper puts forward a routing protocol based on network radius analysis. First, this paper sets up a LEACH model to analyze the nodes’ energy in the networks, and then it builds the network radius model, as the energy of each node in the networks is decease, the network radius of the node is decease also. Finally, this paper simulates the min-hops routing protocol based on the network radius analyze.