Research On Some Related Problems In Wireless Mobile Ad Hoc And Sensor Networks

With the development of modern network technology, the requirements of human society for communication technology in usual life and new applications are proposed unceasingly. Traditionary networks can't fit the requirements of modern society, so the wireless networks are developed rapidly.Wireless Ad Hoc networks are applicated in our society more and more, because they have some characteristics, such as self-organization, self-concrescence and rapid reaction. Wireless Ad Hoc networks have very important significance in theory research and application, especially in some domains these we put more attentions, such as vehicular mobile Ad Hoc networks and Unmanned Aerial Vehicles networks. As a special Ad Hoc network, wireless sensor networks have many applications in military affairs, traffic, special area stakeout, intelligence family, target tracking and public security. So wireless mobile Ad Hoc networks and sensor networks are two hot research domains in wireless Ad Hoc networks, for these special characteristics, there are some research challenges.Based on a systematical summary of wireless Ad Hoc networks and sensor networks, this dissertation focuses on some related sub-researches, such as data delivery scheme of delay tolerant mobile sensor networks, coverage-enhancing of directed sensor networks and routing of mobile Ad Hoc networks , and gains several innovations and achievements. Our research works and contributions of this dissertation are summarized as follows:1. In this dissertation, we propose a new data delivery scheme-PRD (Priority Replication Delivery scheme) for pervasive data gathering in DTMSN (Delay Tolerant Mobile Sensor Networks) that network with intermittent connectivity in space, and we propose another scheme-DAAD(Data Aggregation-based Adaptive Data Reproductive Delivery Scheme) for environment monitoring in DTMSN. PRD consists of two key components for data transmission and queue management, respectively. The former makes decisions on when and where to transmit data messages according to the node delivery probability. The latter employs the message survival time based on priority and delivery copies to decide dropping for minimizing transmission overhead. DAAD consists of data transmission scheme and queue management based on data fusion, respectively. The former makes decisions on when and where to transmit data messages. The latter manages the message queue based on data. Simulation results show that the proposed two data delivery schemes achieve the higher message delivery ratio with the lower transmission overhead and data delivery delay than other DTMSN data delivering approaches.2. In this dissertation, we propose an AFCEA (Artificial Fish-swarm based Coverage-Enhancing Algorithm) and a GSACEA (Genetic Simalated Annealing based Coverage-Enhancing Algorithm) for the problem of coverage-enhangcing in directed sensor networks. Directed sensor is a kind of directional system, and its coverage is different with omni-directional system. In AFCEA, we use our improved optimization algorithm into the solution for coverage-enhancing in directed sensor networks with rotational direction model. By analysis and some simulations, and compare AFCEA to other classic directed sensor networks coverage-enhancing algorithm, AFCEA can achieve higher directional sensor networks coverage with lesser iterative computing times. GSACEA combine the genetic algorithm and the simulated annealing algorithm into the solution for coverage-enhancing in directed sensor networks. By simulations, and compare to other classic directed sensor networks coverage-enhancing algorithm, GSACEA can achieve higher directional sensor networks coverage with lesser iterative computing times too.3. Based on artificial fish-swarm algorithm, in this dissertation we propose a concept named virtual stream, and analyse virtual stream's influence on artificial fish-swarm algorithm, then we propose a VSAFCEA (Virtual Stream Artificial Fish-swarm based Coverage-Enhancing Algorithm). In VSAFCEA, we use our improved artificial fish-swarm optimization algorithm with virtual stream into the solution for coverage-enhancing in directed sensor networks with rotational direction model. By analysis and some simulations, and compare VSAFCEA to other classic directed sensor networks coverage-enhancing algorithm and AFCEA, VSAFCEA can achieve higher directional sensor networks coverage with lesser iterative computing times.4. In this dissertation, a Context-aware optimized link state routing protocol for networks with fast-moving nodes is proposed; CAOLSR (Context-aware Optimized Link State Routing Protocol) adopts a context-aware mechanism, and selects MPR (Multi Point Relays) based on relative movement of nodes, recent access-time and connection number of nodes, and adopts a special flow of MPR selection. In addition, by the introduction of Fisheye, reduces the influence from mobility on the routing accuracy. Experimental results have shown that CAOLSR can achieve good performance and outperform HOLSR (Hierarchical Optimized Link State Routing Protocol), OLSR (Optimized Link State Routing Protocol) and DSDV (Destination Sequenced Distance Vector) in networks with fast-moving nodes.Summaries and prospects have also been put forward in the final of this dissertation.