Networking - Media - UnGuided - Infrared

Infrared waves are a type of electromagnetic radiation with wavelengths longer than visible light but shorter than radio waves. They are commonly used for various applications that require wireless communication and remote control. 

Types of Infrared Waves:

  • Infrared waves can be categorized into three main types based on their wavelengths:
  • Near-Infrared: Near-infrared waves have shorter wavelengths and are often used in applications such as remote controls, infrared data transmission, and short-range communication.
  • Mid-Infrared: Mid-infrared waves have intermediate wavelengths and are used in applications like thermal imaging, spectroscopy, and certain medical diagnostic techniques.
  • Far-Infrared: Far-infrared waves have longer wavelengths and are used in applications such as infrared heating, night vision, and certain types of astronomy.

Applications where Infrared Waves are Widely Used:

  • Remote Control: Infrared waves are extensively used in remote control devices, such as TVs, air conditioners, and home entertainment systems, to transmit signals for controlling various functions.
  • Infrared Data Transmission: Infrared waves can be used for short-range wireless data transmission between devices, such as infrared ports on mobile phones, infrared adapters for transferring data between devices, and infrared communication in certain industrial applications.
  • Security Systems: Infrared waves are employed in security systems, including motion detectors and infrared cameras, to detect movement and monitor areas for surveillance purposes.
  • Medical Applications: Infrared waves are used in medical applications such as infrared thermography, which measures skin temperature for diagnostic purposes, and infrared imaging for non-invasive examination of blood flow and tissue conditions.

Characteristics of Infrared Waves:

  • Non-Ionizing Radiation: Infrared waves are non-ionizing radiation, meaning they do not possess sufficient energy to remove electrons from atoms or molecules, making them generally considered safe for human exposure.
  • Line-of-Sight Communication: Infrared waves require a direct line-of-sight path between the transmitting and receiving devices, as they do not easily penetrate obstacles like walls or other solid objects.
  • Limited Range: The range of infrared waves is limited, typically a few meters to tens of meters, depending on the power of the infrared source and the sensitivity of the receiver.

Advantages of Infrared Waves:

  • Security: Infrared waves do not easily pass through walls or solid objects, providing a level of security and privacy for communication.
  • Immunity to Radio Interference: Infrared waves are not susceptible to interference from radio frequency signals, making them useful in environments with high radio frequency activity.
  • Low Power Consumption: Devices using infrared waves for communication tend to consume less power compared to radio-based communication technologies, making them energy-efficient.

Disadvantages of Infrared Waves:

  • Line-of-Sight Requirement: Infrared waves require an unobstructed line-of-sight path between the transmitter and receiver, which can limit their effectiveness in environments with obstacles or long distances.
  • Limited Range: The range of infrared waves is relatively short, restricting their use to short-range applications and requiring devices to be in close proximity to each other.
  • Sensitivity to Environmental Conditions: Infrared waves can be affected by factors like sunlight, ambient light, and certain materials, which can interfere with the transmission and reception of signals.

Electromagnetic Interference (EMI):

Infrared waves are generally immune to electromagnetic interference (EMI) from other devices operating in different frequency ranges. However, they can be affected by interference from sources that emit strong infrared radiation, such as heat sources or intense light sources.


Attenuation in infrared waves refers to the decrease in signal strength as the waves propagate through the medium. Infrared waves can experience attenuation due to factors such as distance, absorption by materials, scattering, and interference from ambient infrared sources.