Radio diversity for reliable communication in sensor networks

Abstract

Radio connectivity in wireless sensor networks is highly intermittent due to unpredictable and time-varying noise and interference patterns in the environment. Because link qualities are not predictable prior to deployment, current deterministic solutions to unreliable links, such as increasing network density or transmission power, require overprovisioning of network resources and do not always improve reliability.We propose a new dual-radio network architecture to improve communication reliability in wireless sensor networks. Specifically, we show that radio transceivers operating at well-separated frequencies and spatially separated antennas offer robust communication, high link diversity, and better interference mitigation. We derive the optimal parameters for the dual-transceiver setup from frequency and space diversity in theory. We observe that frequency diversity holds the most benefits as long as the antennas are sufficiently separated to prevent coupling. Our experiments on an indoor/outdoor testbed confirm the theoretical predictions and show that radio diversity can significantly improve end-to-end delivery rates and network stability at only a small increase in energy cost over a single radio. Simulation experiments further validate the improvements in multiple topology configurations, but also reveal that the benefits of radio diversity are coupled to the number of available routing paths to the destination.

Performance Analysis of the Industrial Wireless Networks Standard: WIA-PA

“…Frequency hopping, as a class of frequency diverse communication protocols, has been commonly used as a method for IWNs to enable sharing of the 2.4GHz Industrial, Scientific and Medical (ISM) band with other proximate networks, such as IEEE 802.11b/g networks, Bluetooth networks, etc [34,35]. Both blind frequency hopping (BFH) and adaptive frequency hopping (AFH) are widely used frequency hopping techniques by IWNs, where the former is favored by the WirelessHART and ISA 100.11a [25,26] and the latter by WIA-PA [27,40].…”

On balancing between minimum energy and minimum delay with radio diversity for wireless sensor networks

“…Recently, the authors in [1] proposed a multi-radio scheme for WSNs. They explored the diversity in ET X [8] metric present in each radio in order to improve the reliability performance at the cost of increase in energy.…”

“…However, the main difference between this work and the ones in [2] and [3] is that we give a packet priority when routing, so that a node can enable ET X [1] and weighted ET X (W ET X) [2] metrics depending on a traffic class.…”

“…Specifically, in [1], the authors explored radio diversity in order to improve the reliability at the expense of an increase of energy consumption. In their solution, a radio with a better quality, which may be costly in energy, is chosen within a sensor node in order to transmit packets.…”

Communication Range Dynamics Using an Energy Saving Self-Adaptive Transmission Power Controller in a Wireless Sensor Network

“…A node transmitting using always its maximum power, will show a reliability highly immunized to changes in the environment, but the node energy consumption will be unnecessarily soaring. Thus, a trade-off between energy consumption and communication reliability is required, as proposed in diverse strategies (Kotian et al [2], Mahmood et al [3] and Kusy et al [4], among others). In a previous work [5], we propose a self-adaptive strategy, based on fuzzy control, which adapts each node transmission power to achieve an optimal number of neighbors (an optimal node degree).…”