Tsung-Ta Wu

Wireless Sensor Networks for Cattle Health Monitoring

This paper investigates an adaptation of Wireless Sensor Networks (WSNs) to cattle health monitoring. The proposed solution facilitates the requirement for continuously assessing the condition of individual animals, aggregating and reporting this data to the farm manager. There are several existing approaches to achieving animal monitoring, ranging from using a store and forward mechanism to employing GSM-based techniques; these approaches only provide sporadic information and introduce a considerable cost in staffing and physical hardware. The core of this solution overcomes the aforementioned drawbacks by using alternative cheap, low power consumption sensor nodes capable of providing real-time communication at a reasonable hardware cost. In this paper, both the hardware and software have been designed to provide real-time data from dairy cattle whilst conforming to the limitations associated with WSNs implementations.

A Self-Organizing Multi-Channel Medium Access Control (SMMAC) Protocol for Wireless Sensor Networks

This paper proposes a novel multi-channel medium access control (MAC) protocol designed for wireless sensor networks (WSN). Although multiple channel radio communication protocols are well understood in ad hoc wireless and other radio networks, most are not applicable in WSN as sensor nodes which are constrained by low cost and a primitive physical layer. The proposed MAC allows data transmissions take place on multiple channels simultaneously within a single or multiple overlapped radio zones. This MAC applies a light weight, two- tier handshaking algorithm permitting sensor nodes to negotiate a non-occupied channel dynamically. Experimental results show that SMMAC can improve the network performance compared with traditional single channel MAC.

The Impact of Physical Conditions on Network Connectivity in Wireless Sensor Network

In Wireless Sensor Networks, end-to-end routing paths need to be established when nodes want to communicate with the desired destination. For nodes assumed to be static, many routing protocols such as Directed Diffusion have been proposed to meet this requirement efficiently. The performance of such routing protocols is relative to the given network connectivity. This paper addresses mobile sensor nodes taking into account the diversity of scattered node density and investigates how physical conditions impact on network connectivity which in turn influences routing performance. Three analysis metrics: path availability, path duration, and interavailable path time are proposed to quantify the impact of different physical conditions on network connectivity. Simulation results show that the network connectivity varies significantly as a function of different physical conditions.

Wireless telemetry for livestock condition monitoring

The challenges faced by modern agriculture have never been greater. With feedstock and labour prices increasing and constant pressure from retailers to keep food prices low, profit margins are at a point where farmers cannot grow their business to longer-term economically viable sizes. Recent high profile welfare threats such as the BSE and Foot and Mouth outbreaks in the UK have further weakened the financial positions of many in the industry. This paper examines the application of WSNs to livestock monitoring and the issues that accompany the timely reporting of animal health or welfare conditions to farm management. The focus lies mainly on the challenges stemming from data transportation from cattle mounted sensory devices in particular and maintaining sensory node support independent of animal mobility. The core of this study is to overcome the aforementioned drawbacks by using alternative cheap, low power consumption sensor nodes capable of providing real-time communication at a reasonable hardware cost. In this paper, both the hardware and software has been designed to provide a solution which can obtain real-time data from diary or beef cattle whilst conforming to the limitations associated with WSNs implementations.