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Millimeterwave TechnologyMillimeter-wave TechnologyEvery technology has its pro's and con's. The good thing about FSO (Laserlink) is the high bandwidth, the security and good price/value relation. The bad thing about FSO (Laserlink) is the sensibility for bad weather and the stability of the mounting. The good thing about Wireless LAN is the easy of the installation and low cost. The bad thing about Wireless LAN is the security issue and the low bandwidth. Millimeter-wave technology Millimeter-wave technology now brings the good things together while avoiding the bad things. With systems for 60 and 70GHz you can have ease of installation, high security, high bandwidth and availability even with bad weather. While 70GHz is only used outdoors, 60GHz is allowed in- and outdoors. Indoors the output energy for 60GHz is limited to only 25dm, while outdoors 55dbm are allowed. Different frequency spectrum's are assigned for use indoors (57-66GHz) and outdoors (59-63GHz). Free line of sight Of course these systems also need a free line of sight outdoors between the two points where you want to install the devices to really reach the nominal distances. Any mast is good enough. There are sets available for distances of up to 1000 meter, which is normally enough in most applications. Using 60GHz indoors has only very limited distance chances. We will mainly use that technology for connecting Bluray players to our big LCD or LED TVs. Three things Three things should be mentioned about MMW (Millimeter-wave) Technology. Not a cheap solution It is not really a cheap solution. For 70GHz you need a license while 60 GHz is free for public use. Heavy Rain Heavy rain has impact on your link. The 60 and 70GHz Wireless LAN Kits are sorted into categories (depending on their distance) that allow at least 99,999% availability in European regions. It is not the number of rainy days that has an impact on that statistical number, but the heaviness of the rain. Normally you would expect that countries like UK are really bad for that technology. It is not, UK is as good as Belgium or Germany. Regions with rain like a monsoon are bad for that technology. Southern France for example. Best results are attainable in the Northern European countries like Sweden, Norway and Finland. Less Throughput with 60GHz While 70GHz offers you full Gigabit throughput, 60GHz technology only offers 800-850Mbps throughput. You should not see the licensing fact as an issue, but as a chance. By licensing the system for your area, you can be sure that the frequency is yours, avoiding any kind of interferences in the future as seen with 802.11anything technology. |