Introduction

Wireless connection is the connection from the wireless device (supports wireless technology) from any area without any wires linking him.

 The idea of ​​wireless communications Wireless Communications, based on a simple idea; is indispensable for the full "wiring" and the provision of various telecommunications services to users everywhere: at home, in the car, in the plane, in the vessel, in institutions, in universities ... etc.. On the other hand, provide the same services and features offered by telecommunications. For example, used a wired computer networks such as Wired Computer Networks LANs and MANs and WANs and then came the wireless networks WLANs, known commercially by Wi-Fi and then came the WiFi WiMax. While the WiFi cover small areas can be used at home, in offices, in universities, in restaurants, in hotels what is known as Hotspots areas that you can connect wirelessly to different computers or to connect wirelessly to the Internet in the event were present in those areas. The WiMax networks are based on the same idea, but covering a much larger geographical areas than those covered by the networks, WiFi, (at the city level). Of course, the data transfer rate Data Rate in wireless networks, less than in wired networks, and also suffer from problems such as security and protection, and the problems of overlapping waves Interference.

 The other hand should be aware that there are contacts oriented wireless and wireless communication is directed

 1 - non-wire communications directed antennas are used and directed them as an example of a simple mobile phone network, and the use of these antennas has many benefits, including:

 A - contribute to a reduction in confusion and overlap between the frequencies where there is specific guidance to indicate

 B - thus lead to the possibility of the use of frequencies several times in different places while maintaining the non-overlapping

 C - contribute guidance in reducing the transmission power because the goal is not specific and therefore are random savings in energy consumption

 D - the privacy of large

 For - the lack of noise in Channel  itself.-non-directed wireless communications as an example and clear it of  broadcasting and broadcasting tower TV  where there is one central city and the signal is broadcast in all regions and can high for comprehensive coverage of the city.