Bio-telemetry involves the remote measurement and transmission of biological data. It has two main elements - a measurement subsystem that detects physiological signals and converts them to electrical data, and a communication subsystem that transmits the data via wired or wireless methods to receiving devices. Common types of bio-telemetry systems include those using wired connections, short-range radio transmitters, or satellite transmission of patient medical data from sensors.

1. Bio-Telemetry
 The term telemetry is derived from the two Greek terms: “tele”
and “metron”, which mean “remote” and “measure”.
 In general, a physical variable or quantity under
measurement, whether local or remote, is called a measurand.
 Telemetry is a technology that allows the remote
measurement and reporting of information of interest to the
system designer or operator.
 Literally, biotelemetry is the measurement of biological
parameters over a distance.
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2. Elements of Telemetry
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3. Elements of Telemetry
1. Transducer or Sensor:
• Converts the physical variable to be telemetered into an
electrical quantity.
2. Signal Conditioner-1:
• Converts the electrical output of the transducer (or sensor)
into an electrical signal compatible with the transmitter.
3. Transmitter:
• Its purpose is to transmit the information signal coming
from the signal conditioner-1 using a suitable carrier signal to
the receiving end.
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4. Elements of Telemetry
 The transmitter may perform one or more of the following
functions:
 (i) Modulation: Modulation of a carrier signal by the
information signal.
 (ii) Amplification: As and if required for the purpose of
transmission.
 (iii) Signal Conversion: As and if required for the purpose of
transmission.
 (iv) Multiplexing: If more than one physical variables need to
be telemetered simultaneously from the same location, then
either frequency-division multiplexing (FDM) or time-division
multiplexing (TDM) is used.
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5. Elements of Telemetry
 Receiver: Its purpose is to receive the signal(s) coming from
the transmitter (located at the sending end of the telemetry
system) via the signal transmission medium and recover the
information from the same.
 It may perform one or more of the following functions:
1. Amplification
2. Demodulation:
3. Reverse Signal Conversion
4. De-multiplexing
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6. Elements of Telemetry
 Signal Conditioner-2: Processes the receiver output as
necessary to make it suitable to drive the given end device.
 End Device: The element is so called because it appears at the
end of the system.
 End device may be performing one of the following
functions:
1. Analog Indication:
2. Digital Display
3. Digital Storage
4. Data Processing
5. Closed-Loop Control
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7. Subsystems of Telemetry System
 (a) Measurement Subsystem:
 It comprises the transducer (or sensor), signal
conditioner and the end device, like any conventional
measurement system.
 (b) Communication Subsystem:
 It comprises the transmitter and receiver along with the
transmission medium linking the two, like any
communication system.
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8. Telemetry Classification Based on Transmission
Medium
1. Wire-Link Telemetry or Wire Telemetry
2. Radio Telemetry or Wireless Telemetry
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9. Wired Telemetry
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10. Elements of Wired Bio-Telemetry(Analog)
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11. Elements of Wired Bio-Telemetry(Digital)
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12. Elements of Wired Bio-Telemetry
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13. Elements of Wireless Bio-Telemetry
 A typical biotelemetry system comprises:
1. Sensors appropriate for the particular signals to be
monitored
2. Battery-powered, Patient worn transmitters
3. A Radio Antenna and Receiver
4. A display unit capable of concurrently presenting
information from multiple patients
• It is two types
1. Short-Range Radio Telemetry
2. Satellite-Radio Telemetry
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14. Elements of Basic Wireless Bio-Telemetry
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15. Elements of Wireless Bio-Telemetry
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16. Wireless Bio-telemetry Transmitter
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17. Wireless Bio-telemetry Receiver
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18. Elements of Wireless Bio-Telemetry
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19. Telemetry Classification Based on Modulation Method
DC Telemetry Systems
 1. Direct voltage telemetry system
 2. Direct current telemetry system
AC Telemetry Systems
 1. Amplitude modulation (AM) telemetry system
 2. Frequency modulation (FM) telemetry system
 Pulse Telemetry Systems
 1. Pulse amplitude modulation (PAM) telemetry system
 2. Pulse width modulation (PWM) telemetry system
 3. Pulse phase modulation (PPM) telemetry system
 4. Pulse frequency modulation (PFM) telemetry system
 5. Pulse code modulation (PCM) telemetry system
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20. Direct Current Telemetry
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21. FM Radio Telemetry
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22. Single Channel PWM Telemetry
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23. Single Channel PCM Telemetry
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24. Portable Telemetry
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25. Portable Telemetry
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