On Thu, Nov 21, 2002 at 02:48:56PM -0800, Jack Grimes wrote: > HPWREN reduces power on 72-mile WLAN link > > Responding to complaints, the High Performance Wireless Research and > Education Network has reduced power on a 72-mile, 2.4-GHz link it maintains > from San Diego to San Clemente Island. > > Full article at: > http://computerworld.com/newsletter/0%2C4902%2C76118%2C0.html?nlid=PM > > > They reduced the power from 1W to 250mW. I wonder if this isn't still above > the 1W EIRP due to their antenna's gain. Data rate dropped to ~300KBits/sec. > Still, 72 miles is remarkable!
If this is a point to point link they are not restricked to 1W EIRP. At 2.4 GHz they are restricted to reducting the maximum transmitter power of 1 watt (30dBm) a 1/3 of a dB for every dBi of gain over 6 dBi. Since 24 - 6 = 18 and 18 / 3 = 6, then they need to reduce the transmitter to 30 - 6 or 24 dBm (.25 watts). This gives them an EIRP of 24 + 24 or 48 dBm (64 watts). Of course at 5.8 GHz there are different restrictions on power. Tim -- general wireless list, a bawug thing <http://www.bawug.org/> [un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless
