1 / 12

Wireless technology

Wireless technology. Wireless technology. Electromagnetic waves. Transmission of radio-waves and microwaves. Transmission of infrared waves. Radio wave-based networking. Electromagnetic waves. Electromagnetic waves: Transmit data across the atmosphere.

luke
Télécharger la présentation

Wireless technology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Wireless technology

  2. Wireless technology Electromagnetic waves Transmission of radio-waves and microwaves Transmission of infrared waves Radio wave-based networking

  3. Electromagnetic waves • Electromagnetic waves: • Transmit data across the atmosphere. • Are categorized according to frequency ranges. • Frequency ranges are based on repeating patterns of a waveform. • One complete waveform is called a cycle. • Frequency is the number of times a cycle occurs in one second. • Include: • Radio waves • Microwaves • Infrared waves Crest One cycle Trough Electromagnetic spectrum More Wavelength

  4. Wavelength • The length of a wave is the distance between two crests or two troughs. • The frequency of a wave is the number of times a cycle occurs in one second. • The Greek letter, lambda (λ) is used to indicate wavelength. Wave frequencies Back

  5. Transmission of radio- and microwaves • Works on the principle of producing a carrier wave. • A carrier wave is a set frequency that is used to carry data. • A carrier wave is mixed with the data signal. This process is called modulation. • A carrier wave must be at a higher frequency than the digital data signal. • The frequency range occupied by a modulated carrier wave is called the bandwidth. • A carrier wave with a width of 200 kHz has a bandwidth of 200 kHz. • The bandwidth of the carrier wave is referred to as a channel. Carrier wave Carrier wave Signal wave Signal wave Amplitude modulated wave Frequency modulated wave

  6. Transmission of radio- and microwaves • Modulation takes place during radio broadcasting. A transmitter generates the carrier wave and modulates information into the carrier wave. • A receiver receives the modulated wave and demodulates it.

  7. Transmission of infrared waves • Infrared waves lies in between visible light spectrum and microwaves. It has wavelength of 700 nm to 1 mm and frequency ranges from 300 GHz to 430 THz. • Infrared waves is transmitted as a series of digital light pulses. • Infrared waves are used for very short range communication purposes such as television and it’s remote. • Infrared travels in a straight line so they are directional by nature.

  8. Radio wave-based networking • There are three basic types of radio wave-based networking. • Wi-Fi: • Wi-Fi means wireless fidelity. • Wi-Fi operates on a higher frequency (2.4 GHz – 5 GHz) than cell phones. • Uses radio-waves to transmit information to and from the Internet or computer. • An access points act as a central transmitter and receiver of wireless radio signals. • Most computers and other devices contain built-in access points. USB type wireless access point

  9. Radio wave-based networking • Information from the access point is send to a wireless router. • The router converts it to radio-waves and beams it to a computer. • The computer interprets the radio-waves with the help of hardware (Access point) and software. Mobile wireless router Wireless router

  10. Radio wave-based networking • Bluetooth: • The name ’Bluetooth’ reflects the Scandinavian origins of the technology. It is named after a 10th century Danish viking, King HaraldBlåtand (translating as 'Bluetooth' in English). • Bluetooth is a short range wireless system designed for limited distances. • The frequency ranges from 2.4 GHz – 2.585 GHz. • A Bluetooth network is referred to as a piconet or Personal Area Network (PAN). Two piconets linked A piconet Bluetooth and toys Bluetooth in medicine How does Bluetooth work?

  11. Radio wave-based networking • Cellular technology: • A cellular network or mobile network is a wireless network distributed over land areas called cells, each served by at least one fixed-location transceiver, known as a cell site or base station. • Radio-waves connect to designated areas referred to as cells. • A remote device (e.g. Mobile phone) connects to a radio transceiver within a cell. Cell Transceiver (base station) How does a cell phone work

  12. Electromagnetic spectrum Back

More Related