Delay-Reliability Trade-off in MIMO-Enabled IEEE 802.11-Based Wireless Sensor and Actuator Networks

AbstractOne of the main challenges in Wireless Sensor and Actuator Networks (WSAN) is the delay caused by shared and nondeterministic behavior of wireless communication medium. The Retry-Limit parameter of IEEE 802.11 standard can be used to control packet reliability, whereas other parameters mostly effect on the packet delay. In this paper, at first the delay-reliability trade-off in WSANs based on MIMO-Enabled IEEE 802.11 standard, utilizing Enhanced Distributed Channel Access (EDCA) at Medium Access Control (MAC) layer and Maximum Likelihood Spatial Multiplexing at PHYsical (PHY) Layer is studied. Then two simple adaptive schemes have been proposed to minimize packet delay while satisfying the required reliability at noisy factory environment

Efficient Retransmission QoS-Aware MAC Scheme in Wireless Sensor Networks

In this paper, an Efficient Retransmission Random Access Protocol (ERRAP) is designed that combines scheme of collision avoidance and energy management for low-cost, short-range wireless radios and low-energy sensor nodes applications. This protocol focuses on efficient Media Access Control (MAC) schemes to provide autonomous Quality of Service (QoS) to the sensor nodes in one-hop QoS retransmission group in WSNs where the source nodes do not have receiver circuits. These sensor nodes can only transmit data to a destination node, but cannot receive acknowledgement or control signals from the destination node. The proposed scheme ERRAP provides QoS to the nodes which work independently on predefined time by allowing them to transmit each packet an optimal number of times within a given period. Our simulation results demonstrate the superiority of ERRAP scheme which increases the delivery probability and reduces the energy consumption

QOS GROUP BASED OPTIMAL RETRANSMISSION MEDIUM ACCESS PROTOCOL FOR WIRELESS SENSOR NETWORKS

This paper presents, a Group Based Optimal Retransmission Medium Access (GORMA) Protocol is designed that combines protocol of Collision Avoidance (CA) and energy management for low-cost, shortrange, low-data rate and low-energy sensor nodes applications in environment monitoring, agriculture, industrial plants etc. In this paper, the GORMA protocol focuses on efficient MAC protocol to provide autonomous Quality of Service (QoS) to the sensor nodes in one-hop QoS retransmission group and two QoS groups in WSNs where the source nodes do not have receiver circuits. Hence, they can only transmit data to a sink node, but cannot receive any control signals from the sink node. The proposed protocol GORMA provides QoS to the nodes which work independently on predefined time by allowing them to transmit each packet an optimal number of times within a given period. Our simulation results shows that the performance of GORMA protocol, which maximize the delivery probability of one-hop QoS group and two QoS groups and minimize the energy consumption

Robust Controller for Delays and Packet Dropout Avoidance in Solar-Power Wireless Network

Solar Wireless Networked Control Systems (SWNCS) are a style of distributed control systems where sensors, actuators, and controllers are interconnected via a wireless communication network. This system setup has the benefit of low cost, flexibility, low weight, no wiring and simplicity of system diagnoses and maintenance. However, it also unavoidably calls some wireless network time delays and packet dropout into the design procedure. Solar lighting system offers a clean environment, therefore able to continue for a long period. SWNCS also offers multi Service infrastructure solution for both developed and undeveloped countries. The system provides wireless controller lighting, wireless communications network (WI-FI/WIMAX), CCTV surveillance, and wireless sensor for weather measurement which are all powered by solar energy