Computer Science- Unaided

  Introduction to IR Signals Infrared (IR) signals are a type of electromagnetic radiation with wavelengths longer than visible light but shorter than microwaves, typically ranging from 850 nm to 950 nm. These signals are invisible to the human eye but are widely used in wireless communication for consumer electronics, remote controls, motion sensors, and data transfer. IR signals work by transmitting modulated infrared light pulses from a transmitter (IR LED) to a receiver (IR sensor or photodiode), which decodes the pulses into commands for controlling devices. This technology is simple, cost-effective, and reliable, making it a staple in home automation, entertainment systems, and security applications. However, IR communication has limitations, such as line-of-sight requirements and a short range (typically 5-10 meters). Despite the rise of Wi-Fi and Bluetooth, IR signals continue to play a crucial role in remote control technology and motion detection systems.   ...

  Introduction of Radio Waves Radio waves are a type of electromagnetic radiation with wavelengths longer than infrared light. They have frequencies ranging from about 3 Hz to 300 GHz and are widely used in communication systems, including radio broadcasting, television signals, mobile phones, satellite transmissions, and Wi-Fi networks . Properties of Radio Waves: Long Wavelengths – They range from millimetres to hundreds of kilometres in length. Low Energy – Compared to other electromagnetic waves like X-rays or ultraviolet rays, radio waves have lower energy. Ability to Travel Long Distances – Radio waves can propagate over large distances, making them ideal for communication. Reflection, Refraction, and Diffraction – They can bounce off surfaces, bend around obstacles, and spread out after passing through narrow openings. Uses of Radio Waves: Communication: AM/FM radio, television, mobile phones, and walkie-tal...

  Wireless Networking (WIFI) Wi-Fi is wireless networking technology enabling various devices like computers, smartphones, and other equipment to connect to the Internet and communicate with each other without a cable. It creates a network where these devices can exchange information. These established connections through a wireless router act as an intermediary between the WiFi-compatible devices and the Internet. This technology allows seamless internet access and device communication in homes, offices, and in public spaces. Types of Wi-Fi Standards Year of Release Description Wi-Fi-1 (802.11b) 1999 This version has a link speed from 2Mb/s to 11 Mb/s over a 2.4 GHz frequency band Wi-Fi-2 (802.11a) 1999 After a month of release previous version, 802.11a was released and it provide up to 54 Mb/s link speed over 5 Ghz band Wi-Fi-3 (802.11g) 2003 ...

  BLUETOOTH Bluetooth is a wireless technology that lets devices like phones, tablets, and headphones connect to each other and share information without needing cables. Bluetooth simply follows the principle of transmitting and receiving data using  radio waves . It can be paired with the other device which has also Bluetooth but it should be within the estimated communication range to connect. When two devices start to share data, they form a network called piconet which can further accommodate more than five devices. Key Features of Bluet ooth The transmission capacity of Bluetooth is 720 kbps. Bluetooth is a wireless technology. Bluetooth is a Low-cost and short-distance radio communications standard. Bluetooth is robust and flexible. The basic architecture unit of Bluetooth is a  piconet   Architecture of Bluetooth The architecture of Bluetooth defines two types of networks: Piconet Piconet is...