Topic: Communication Systems
The coding system typically used in digital telemetry is
- A. PPM (Pulse Position Modulation)
- B. PAM (Pulse Amplitude Modulation)
- C. PCM (Pulse Code Modulation)
- D. PDM (Pulse Duration Modulation)
Answer: C. PCM (Pulse Code Modulation)
Explanation: In a digital telemetry system, the sensor picks up the physical quantity and converts it into an electrical analog form. To transmit this analog data using a digital system, it must first be converted into digital form. For this purpose, Pulse Code Modulation (PCM) is used. PAM, PPM, and PDM are pulse-analog modulation schemes, not purely digital techniques.