دوری‌سنجی

Also known as telemetering

thumb|An expendable dropsonde used to capture weather data. The telemetry consists of sensors for pressure, temperature, and humidity and a wireless transmitter to return the captured data to an aircraft. thumb|300px|A saltwater crocodile with a GPS-based satellite transmitter attached to its head for tracking Telemetry is the in situ collection of measurements or other data at remote points and their automatic transmission to receiving equipment (telecommunication) for monitoring. The word is derived from the Greek roots tele, 'far off', and metron, 'measure'. Systems that need external instr