In the simplest of terms, telemetry is the transmission of measurement data from one location to another. When we look at the etymology of telemetry, it's Greek derivative literally translates as remote measure. In the context of telemetry, a telemeter remotely captures data in the field and transmits the measurements to a system that records and processes the information.
How Telemetry Works
The telemeter automatically captures measurements via a sensor. A typical sensor measures or detects physical properties like temperature, moisture, pressure, location, and more. (Wikipedia has an exhaustive list of sensors.)
As the sensors capture data, the telemeter sends the information to a receiving system. Typically, the receiving systems and telemeters are not located in near proximity, so data is transmitted wirelessly, although it's not uncommon for hard-wired systems to be used in certain environments. These hard-wired systems may transmit data via existing phone lines or networking cables.
Upon recording and processing the data, the receiving system may send automated commands or simply relay the information to a master system for further monitoring.
Industry 4.0 & Telemetry Technologies
Industry 4.0 captures the connectivity revolution seen across manufacturing and other industrial segments. As Industry 4.0 technologies continue to mature, the economies of scale have lowered hardware costs making it more practical than ever to monitor environments and assets at increasingly large volumes.
The advent of edge computing and networking has introduced telemetry to a whole new level of utility. Edge computing devices process the massive amounts of captured data near the point of initial measurement. Typically, the data capture is in remote areas, or the "edge" of networks. The edge devices allow the information to be accessible in real-time and locally. This is particularly useful in scenarios where monitoring remote areas is crucial, yet it's not necessary to send all the data immediately to the cloud. For example, an oil rig would have telemeters monitoring any number of measures. In this scenario, the telemetry data would be transmitted to the edge device, which would process the information on premise, before ultimately sending a report to the cloud later.
Cellular Networks & LPWAN
5G cellular networks will further augment telemetry's ability to provide real-time data streams for analysis. 5G cellular networks will have wider coverage, lower latency, and more bandwidth. In more generic terms, 5G cellular networks will transmit massive amounts of data over a stronger and faster signal. As telemeters transmit data to the receivers, the receivers can then immediately send the data to the cloud for processing and transformation in real-time, then receive back the processed data to fire off automated controls or simply for display. As the use of LPWA (low power, wide area) technology becomes more prevalent, the telemeters will be capable of periodically transmitting the data directly to the cloud and skip the receivers.
Telemetry and RFID
Passive RFID sensors capture measurements and transmit the data to the RFID reader. Unlike LPWAN tech which still has a battery, passive RFID sensors operate without a traditional power source. The radio waves from the RFID reader power and activate the RFID sensor, which transmits data back to the RFID reader. Since passive RFID tag sensors have no battery, it's much more economical to enable item-level measurement and tracking at scale. For example, someone involved in the floral industry may want to monitor the moisture and temperature levels of flowers as they're being shipped from one location to another.
Telemetry allows for the constant monitoring of assets and physical properties no matter the location. Often times, it's not physically possible to visit each monitoring station, so the ability to transmit the telemetry data to a centralized data warehouse enables large scale monitoring operations.