![]() ![]() Presently, the IEEE standards committee is working on the next generation of the existing IEEE 802.11g standard that will include advanced technologies to enhance performance of broadband wireless LANs.įigure 1: Multipath phenomena in wireless communication Of course there has been much research and development in recent years to overcome such factors limiting the stability and range of wireless broadband links. ![]() In a home environment, the user may find he can only use a laptop a limited range while in the workplace several APs may be required to eliminate dead spots and allow wireless access to cover the entire floor. Performance fluctuations like this are frustrating for the user, and, indeed, unacceptable for future applications that require stable, high throughput connections. Wi-Fi users may also experience locations at home where the signal strength is weak, or where dropouts occur intermittently. Places where this happen in a typical user setting, such as a corner room away from the transmitter (AP), are called "dead spots". For example, if two signal paths are received out of phase, the total signal may cancel out entirely. The receiver is designed to correct signal distortion, but can only do so to within certain limits. The total signal is the sum of all signals according to their phase relationships and in general, the received signal is spread out in the time domain. At the receiver, the signal loses quality because the obstacles cause the signal path lengths to be unequal, which results in several time-delayed copies of the information signal arriving at the receiver, as depicted in Figure 1. ![]() Often, Wi-Fi transmission is limited by a phenomenon called multipath: In an obstacle-rich environment the signal bounces off the obstacles (for example, brick walls, office furniture, etc.), in the process generating reflected signals which degrades the reception of the signal. NEXT GENERATION WIRELESS CHALLENGES: Overcoming Multipath Enables high-security radio encoding via WPA2/WPA (downward compatible with 128/64 bit WEP) Kaspersky Internet Security with 3-month update service mounting material for wall and ceiling mounting Additional RJ-45 network connection for integrating the camera into an existing 10/100 Mbps network viewing & recording program for up to 4 cameras at the same time User friendly installation and configuration via Internet Explorer Allows wireless encryption via WPA/WPA2 as well as 128/64 bit WEP ![]() Manual, time-controlled or cylic recording This picture is sent by email or uploaded to a FTP server if there is some motion in the field of view of the camera, a picture is recorded. audio signals can be played back if a speaker is connected to the camera) MPEG4 and Motion JPEG picture mode with 24 bit digital colour Powerful, mobile monitoring system with swivel, tilt and zoom function Wireless LAN internet camera for monitoring a house, shop and garden ![]()
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