networking and data exchange between PCs, it was time that computer developers came up with something more feasible and convenient. Garnering basic inspiration from radio signal transmission that revolutionised wireless communication, transmission of wireless data started from infrared communication. From humble beginnings of only a few bits per second in only select state of the art technology laboratories of its time in the early 1980s, it has now become one of the fastest and safest modes of communication. Today anything measured below megabits per second is considered slow and even in technologically backward countries like Nepal, speed of a few hundred kilobytes can be obtained. The upper limit is also constantly being challenged and is now set at a whopping 500 megabytes per second achieved in January 2010 in Siemens labs. Some of the popular and beneficial modes of wireless communication in the computer industry are as follows.
From night vision to thermal imaging, remote sensing and tracking, infrared prospered in the field of wireless communication as well. In the early years, infrared wireless communication was a huge sensation. Known as IR, this technology is based on the principal of harnessing energy of electromagnetic waves to send and receive data and relies on infrared LEDs which is polarized using a narrow modulated plastic beam. Infrared is commonly found in mobile phones for sharing contacts, images and other media objects. PCs with IR wireless installed in them can use this feature as well.
Cons: Short range (requires line of sight) less bandwidth.
In 1994, Ericsson launched a new mode of wireless technology which was better than infrared in both range as well as bandwidth. However, the system that this wireless technology latches upon is different than infrared. Bluetooth uses a radio technology called frequency-hopping spread spectrum, which chops up the data being sent and transmits chunks of it on up to 79 bands. Bluetooth is a packet-based protocol with a master-slave structure. Today, literally every cell phone has this feature for data transfer. In PCs latest laptops come with Bluetooth adapter inbuilt. However for those that do not, there’s nothing to worry. USB dongles and adapters are easily available that allow your device to be connected to others via Bluetooth in a highly secured manner. Bluetooth remote controls and wireless headsets are available for wireless communication and device control as well.
Pros: Low power consumption, compact
Cons: Low range, low transfer speed.
Wi-Fi networks originate from a source known as access point. This access point, usually a wi-fi enabled router or disc, generates a signal which then transfers itself away from the point of origin. Wi-Fi technology is inbuilt today in most laptops, hand held tablets and also high end smart phones.
Satellite communications chiefly includes three areas of commercial use; satellite phones used to communicate anywhere in the world and the use of satellites to transfer long distance calls, transfer of TV signals and the use of satellite uplinks to create a personalised hub of internet access—one of the fastest methods available. This vast exploitation of satellites is even more impressive given the fact that high end data encryption makes it hardest to hack. Although satellite TV is found all around the world and is relatively inexpensive, using satellite phones and having personalised uplink is an expensive endeavour. Therefore satellites are not as common form of communication as its usefulness may suggest but as ground waves become increasingly crowded, the use of satellites will increase in the future.
Mobile Communications (3G/GPRS/CDMA)
Motorola launched its first phone, DynaTAC 8000x in 1983 and the world has not been the same since. The primitive forms of networks that were found in the yesteryears are today being replaced by more faster ways to communicate. 3G for instance has made video calls possible making them more realistic. Also GPRS and CDMA technology are pushing the boundaries of mobile internet further.
Source : The Kathmandu Post