Home General Knowledge GK SPECIAL TOPIC : SOME NEW TERMS IN MOBILE TECHNOLOGY
GK SPECIAL TOPIC : SOME NEW TERMS IN MOBILE TECHNOLOGY
Friday, 18 July 2014 08:20

 



SOME NEW TERMS IN MOBILE TECHNOLOGY

WiBro

WiBro (Wireless Broadband) is a wireless broadband Internet technology developed by the South Korean telecoms industry. WiBro (Wireless Broadband) communication technique uses radio waves (frequency of 2.3 GHz) and allows a maximum theoretical speed of 30 megabits per second over a range between 1 and 5 kilometers. WiBro is a wireless point to point communication technique, tailored to serve low-cost sparsely populated areas where the fiber is not an option.

GPRS

General Packet Radio Services (GPRS) is a packet-based wireless communication service that promises data rates from 56 up to 114 Kbps and continuous connection to the Internet for mobile phone and computer users.

GPRS facilitates instant connections whereby information can be sent or received immediately as the need arises, subject to radio coverage. No dial-up modem connection is necessary. This is why GPRS users are sometimes referred to be as being "always connected".

GPRS packet-based services cost users less than circuit-switched services since communication channels are being used on a shared-use, as-packets-are-needed basis rather than dedicated to only one user at a time. Packet switching means that GPRS radio resources are used only when users are actually sending or receiving data. Rather than dedicating a radio channel to a mobile data user for a fixed period of time, the available radio resource can be concurrently shared between several users. This efficient use of scarce radio resources means that large numbers of GPRS users can potentially share the same bandwidth and be served from a single cell.

WAP

Wireless Application Protocol (WAP) is a secure specification that allows users to access information instantly via handheld wireless devices such as mobile phones, pagers, two-way radios, smartphones and communicators. WAP is supported by all operating systems WAPs that use displays and access the Internet are called microbrowsers i.e. browsers with small file sizes that can accommodate the low memory constraints of handheld devices and the low-bandwidth constraints of a wireless-handheld network.

Although WAP supports HTML and XML, the WML language (Wireless Markup Language) is specifically devised for small screens and one-hand navigation without a keyboard.

GSM and CDMA

GSM

GSM (Global System for Mobile communication) is a digital mobile telephony system that is widely used in Europe and other parts of the world. GSM uses a variation of time division multiple access (TDMA) and frequency division multiple access (FDMA). GSM digitizes and compresses data, then sends it down a channel with two other streams of user data, each in its own time slot. It operates at either the 900 MHz or 1800 MHz frequency band. Mobile services based on GSM technology were first launched in Finland in 1991. Today, more than 690 mobile networks provide GSM services across 213 countries and GSM represents 82.4% of all global mobile connections.

The key advantage of GSM systems to consumers has been higher digital voice quality and low cost alternatives to making calls, such as the Short message service (SMS, also called "text messaging"). The advantage for network operators has been the ease of deploying equipment from any vendors that implements the standard. Like other cellular standards, GSM allows network operators to offer roaming services so that subscribers can use their phones on GSM networks all over the world.

CDMA

Code-Division Multiple Access is a digital cellular technology that uses spread-spectrum techniques. Individual conversations are encoded with a pseudo-random digital sequence. CDMA employs analog-to-digital conversion (ADC) in combination with spread spectrum technology. Audio input is first digitized into binary elements. The frequency of the transmitted signal is then made to vary according to a defined pattern (code), so it can be intercepted only by a receiver whose frequency response is programmed with the same code.

CDMA consistently provides better capacity for voice and data communications than other commercial mobile technologies, allowing more subscribers to connect at any given time.

CDMA is a military technology first used during World War II by English allies to foil German attempts at jamming transmissions. The allies decided to transmit over several frequencies, instead of one, making it difficult for the Germans to pick up the complete signal.

The technology is used in ultra-high-frequency (UHF) cellular telephone systems in the 800-MHz and 1.9-GHz bands.