Multi-dimensional Cross-layer Design And Optimization For Multi-service In High Rate WSN

WSN (Wireless Sensor Network) is one of the research focuses, and have been widely used in many fields, such as military, industrial control, biomedical, and environmental monitoring. With the development of WSN and the increase of multimedia application, HRWSN (High Rate Wireless Sensor Network) emerged. It can process data, images, audio, video and other businesses, and can provide QoS (Quality of Service) guarantee. It can be used in some applications like high-quality video surveillance, diversified information collecting and processing, complex task scheduling, high-precision track location. Compared to traditional WSN, HRWSN has stronger capability of data processing and data transmitting. Energy constraint in HRWSN is more serious.Bandwidth’s frequently fluctuatation and instability of the wireless transmission medium can cause signal fading. The traditional hierarchical framework exposed huge drawbacks. Cross-layer design and joint can address this issue. Cross-layer mechanism of HRWSN shares state parameters and QoS parameters between different layers. It can achieve joint optimization under the constraints of system resource and performance requirements. By making full use of system resources, cross-layer mechanism can improve the overall performance of sensor networks. It is an important method to improve energy efficiency and QoS guarantee of multi-services in HRWSN. HRWSN link logical world and real physical world together, it is the key technology during the transformation from sensor networks to the IoT (Internet of Things). IoT has been listed as one of strategical emerging industries.To address the energy constraint and QoS guarantee issues in HRWSN in this dissertation, a multi-services scheduling algorithm named AM-LWDF (Adaptive Modified Largest Wait Delay First) based on cross-layer methond, a real-time scheduling algorithm named MDSA (Multi-Dimensional Scheduling Algorithm) based on multi-dimensional joint optimization, a rate adaption MAC named AMAC (Adaptive MAC), and a multi-servicees hybrid MAC protocol named RHMAC (Rate-adaptive Hybrid Medium Access Control) based on cross-layer are proposed. The main contents and innovations are listed as the following four aspects:1. To support the QoS guarantee of multi-services in HRWSN, a scheduling and resource management algorithm named AM-LWDF based on cross-layer is proposed, which put parameters of physical layer, data link layer and application layer into consideration. A mathematical model is proposed with the goal of maximizing the throughput under QoS constraints of real-time business. It can achieve a compromise between delay of real-time business, throughput of non real-time business, energy efficiency, and fairness among different service.2. To meet special requirement of real-time scheduling in heterogeneous HRWSN, a scheduling algorithm named MDSA is proposed which consider the task deadline, QoS, throughput, QoS fairness and load balancing. To evaluate the performance of MDSA, MDSA is compared to DASAP and DALAP. Simulation results show that MDSA is significantly better than DASAP and DALAP in the terms of guarantee ratio, QoS, scheduling span, load balancing under the heterogeneous distributed environment.3. Constant duty-cycle of SMAC could not adapt different rates of multi-service in HRWSN, so an adaptive MAC named AMAC is proposed in this dissertation, which adopts adaptive rate mechanism and crisscross activation mechanism. It can dynamically adjust duty-cycle according to node rate. Simulation results show that AMAC can improve the throughput and reduce delay effectively compared with the traditional SMAC when the packets burst out. Then a hybrid MAC protocol named RHMAC based on cross-layer optimization is proposed. RHMAC can switch between CSMA and TDMA according to sensor node rate automatically. Simulation results show that RHMAC can achieve higher throughput and energy efficiency than BMAC in multi-hops sensor networks.Finally, a series of smart high rate sensor nodes have been designed in emergency hospital. By using cross-layer design and joint optimization technology QoS guarantee of multi-service is ensured. And accurate location, tracking and management of staff, supplies and equipments have been realized.