Wireless Communication Networks for Gas Turbine Engine Testing

A new trend in the field of Aeronautical Engine Health Monitoring is the implementation of wireless sensor networks (WSNs) for data acquisition and condition monitoring to partially replace heavy and complex wiring harnesses, which limit the versatility of the monitoring process as well as creating practical deployment issues. Using wireless technologies instead of fixed wiring will fuel opportunities for reduced cabling, faster sensor and network deployment, increased data acquisition flexibility and reduced cable maintenance costs. However, embedding wireless technology into an aero engine (even in the ground testing application considered here) presents some very significant challenges, e.g. a harsh environment with a complex RF transmission environment, high sensor density and high data-rate. In this paper we discuss the results of the Wireless Data Acquisition in Gas Turbine Engine Testing (WIDAGATE) project, which aimed to design and simulate such a network to estimate network performance and de-risk the wireless techniques before the deployment

Wireless sensor networks for animal monitoring using both antenna and base-station diversity

Wireless sensor networks are widely used for condition monitoring applications. Much effort has been invested in improving the performance of such networks. Diversity is a well-proven technique in this context. Here, we present the practical application of base station and antenna diversity. Empirical measurements of performance in a realistic environment are reported and a statistical analysis of the resulting data is presented

Effect of antenna height and polarisation on short wireless links

A characterization of the short range (< 100 cm) narrowband wireless channel is presented, appropriate to a dense network of wireless transceivers operating in the 2.4 GHz ISM band. Transmission loss measurements have been made in vertical and horizontal polarisations using rectaxial antennas for a range of antenna heights and separation distances. A preliminary interpretation of the results suggests that surface wave propagation may be significant for short wireless links such as might be used in sensor network applications

Some preliminary short-range transmission loss measurements for wireless sensors deployed on indoor walls

Antenna characteristics and propagation are of fundamental importance to the coverage, capacity and service quality of all wireless communication systems. This paper presents short-range narrowband propagation measurements at 2.445 GHz for sensor network applications in an indoor environment. The effect of sensor node location on a wall has been determined for a pair of linearly polarised rectaxial antennas and a pair of ceramic patch antennas. Propagation loss has been measured as a function of (i) node separation (i.e. link length), (ii) node drop (i.e. vertical displacement of nodes below the ceiling) and (iii) node height (i.e. the perpendicular displacement of the nodes from the wall surface). It is observed that there is no significant effect of wall offset. In addition, the path loss exponent n generally increases with decreasing node drop

Development of a multiple-input multiple-output ultra-wideband system emulator

An experimental testbed is described for the characterization of indoor channels with sufficient spatial resolution and sufficient bandwidth to study the practical capacities of MIMO-UWB systems. UWB measurements have been made in both frequency and time domains for mutual validation. The opportunity has been taken in this paper to extract narrowband transmission loss models from the resulting UWB database. The extraction of a UWB channel model is work in progress

A channel model for wireless sensor networks in gas turbine engines

A narrowband channel model (2.4 GHz to 2.5 GHz) for wireless sensors deployed over the external surfaces of a gas turbine engine is reported. The model is empirical and based on a series of transmission loss measurements over the surface of a gas turbine engine

Effect of antenna height and polarisation on short wireless links

A characterization of the short range (< 100 cm) narrowband wireless channel is presented, appropriate to a dense network of wireless transceivers operating in the 2.4 GHz ISM band. Transmission loss measurements have been made in vertical and horizontal polarisations using rectaxial antennas for a range of antenna heights and separation distances. A preliminary interpretation of the results suggests that surface wave propagation may be significant for short wireless links such as might be used in sensor network applications

Development of a Multiple-Input Multiple-Output Ultra-Wideband System Emulator

An experimental testbed is described for the characterization of indoor channels with sufficient spatial resolution and sufficient bandwidth to study the practical capacities of MIMOUWB systems. UWB measurements have been made in both frequency and time domains for mutual validation. The opportunity has been taken in this paper to extract narrowband transmission loss models from the resulting UWB database. The extraction of a UWB channel model is work in progres