I'm pretty sure I'm FCC rule compliant, considering I use Trango Tlink-45s (DFS certified), just about everywhere that we use 5.4Ghz. I have a lot of 5.4G deployed within a 25 mile radius of DC. I have chosen not to register my links in the TDWR database for a variety of legitimate competitive, strategic, and legal reasons, that have nothing to do with FCC Compliance. Currently the DC area appears clean on the radar maps. However, should anyone else learn otherwise in the future, let me know, I have an open door, and will help if I can.
Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband ----- Original Message ----- From: Patrick Shoemaker To: WISPA General List Sent: Wednesday, February 09, 2011 10:04 AM Subject: Re: [WISPA] IDEAS to help solve the 5 GHz TDWR problem I'm close to IAD, DCA, BWI, and ADW. With so many radars in such a small area I'd imagine some triangulation could be done. DC is not on the FAA's hotlist though... Next weather event I will take a look. -- Patrick Shoemaker Vector Data Systems LLC shoemak...@vectordatasystems.com office: (301) 358-1690 x36 http://www.vectordatasystems.com On 2/9/2011 12:32 AM, Jack Unger wrote: Here are some ideas to help solve the TDWR interference problems around the country and possibly save 110 MHz of spectrum (5570 to 5680 MHz). We may not need to physically go to the problem areas because the data is available online. Here's what we could do: First, I'm attaching an NTIA report about TDWR interference. It contains a picture showing what the interference "strobe" lines look like (see page 7). Once you read this report, you will have a good understanding of the problem and how to look for interference strobes. Second, the TDWR radar outputs can be accessed from <http://www.wunderground.com/radar/map.asp> then select the TDWR radar that you want to monitor. The trick is learning how to configure your view of the radar to be able to see strobes that are present. It requires tweaking with the elevation angle and velocity settings during the presence of actual precipitation conditions being displayed on a radar. I've seen strobes myself after I've played with the radar settings for a while to see what settings make them the most visible. It requires some time for experimentation. I'll ask the FCC for updated "problem airport" information. The last reported problem areas were New York, Chicago, Denver, Dallas and San Juan Puerto Rico. If we can get a volunteer team in each area to monitor their local TDWR during heavy weather, that team can get a general idea of the direction that the strobes are coming from. As the attached report indicates, one UNII transmitter can cause several, slightly different direction strobes so again, it's going to take some practice to figure this out but with practice and dedication from local teams, we should be able to track some of these offending transmitters down. Have a look at the report and experiment with viewing your local radar. Once you figure out what radar settings show the strobes best, PLEASE tell the rest of us. If we put our heads together to address this, we may be able to locate many of these interference sources and save the band without needing strict new FCC regulations. If you want an email list set up for the team in your area (for example, (xxx_area_TDWR_Team), let me know and I'll get the lists set up. I think it's worth a try. Who's on board and which TDWR system are you near? jack 818-227-4220 -------------------------------------------------------------------------------- WISPA Wants You! Join today! http://signup.wispa.org/ -------------------------------------------------------------------------------- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ ------------------------------------------------------------------------------ -------------------------------------------------------------------------------- WISPA Wants You! Join today! http://signup.wispa.org/ -------------------------------------------------------------------------------- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
-------------------------------------------------------------------------------- WISPA Wants You! Join today! http://signup.wispa.org/ -------------------------------------------------------------------------------- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
