Understanding Smart Sensors - Nomads.usp

6Communications for Smart SensorsBehold the people is one, and they all have one language; and this they begin todo: and now nothing will be restrained from them, which they have imaginedto do.—Genesis 11:66.1 IntroductionThe increasing interest in smart sensors is a direct result of the need to communicatesensor information in distributed control systems. Unfortunately,numerous protocols have been defined for data communication in control systems.Industry standards have been and are being developed for various applications.Within a given market segment, several proposals are vying foracceptance. A few of these protocols have already been implemented in siliconhardware. This chapter provides background information, identifies many ofthe proposed protocols, and describes silicon chips that have been developed tosupport system designs. (Chapter 12 goes into the details of the newestIEEE1451 standards developed specifically for sensors.)6.2 Definitions and Background6.2.1 DefinitionsData communication from sensor inputs must be analyzed, with the recognitionthat the sensor is a part of an entire control system. Several industry119