THE IEEE 1451.5 WIRELESS SMART TRANSDUCER INTERFACE STANDARD

THE IEEE 1451.5 WIRELESS SMART TRANSDUCER INTERFACE STANDARD

The development of wireless sensor network technology and standards is not being driven solely by the communications interface. Manufacturers, implementers, as well as users of sensors have expressed a desire for wireless connectivity.^[7] This need has been recognized by the IEEE, and has led to the formation of the IEEE 1451.5 Wireless Sensor Working Group.^[8]

The IEEE 1451 family of standards (e.g., Std. 1451.1–1999^[9] and Std. 1451.2–1997^[10]) is sponsored by the Technical Committee on Sensor Technology of the IEEE Instrumentation and Measurement Society. The development of these standards followed a meeting in 1993 that was cosponsored by the IEEE and the National Institute of Standards and Technology, a division of the U.S. Department of Commerce, to address the issue of transducer compatibility. Manufacturers were finding it difficult to produce transducers compliant with the increasingly large number of network communication protocols. The solution was the development of a smart transducer interface, which is a single communication protocol usable by all sensors; this effort became IEEE 1451.

One of the major benefits provided by the IEEE 1451 standardization process was the creation of a standard Transducer Electronic Data Sheet (TEDS) in IEEE 1451.2.^[11] This standard facilitated the use of smart sensors by standardizing the interface between the sensors and the "Network Capable Application Processor (NCAP)" (i.e., the protocol-handling processor between the sensor and the network). As part of this standardization, the TEDS was created to provide a way in which the transducers can describe themselves to measurement systems, control systems, and, in general any device on the network. Representation of almost every conceivable parameter associated with the transducer, including its manufacturer, calibration, and performance parameters, can be represented in its TEDS. This greatly enhances interoperability between sensors and actuators, and makes the communication network sensor-agnostic; it can communicate equally well with thermometers, psychrometers, and robotic actuators. Because the transducer-NCAP interface is standardized, the network need only have a single NCAP design for the communication protocol it uses, which can then be duplicated for each sensor.