BEACON CONTROL OF RADIO TRANSMITTERS TO REDUCE RADIO FREQUENCY INTERFERENCE
Original Publication Date: 1992-Aug-01
Included in the Prior Art Database: 2002-Jan-15
The out-of-band emanations f?om a mobile unit radio frequency (RF) transmitter may cause interference to sensitive receivers if ttie mobile unit is too close to the sensitive receiver. The mobile units used in the IRIDIUMM system may interfere with radio astronomy (RA) measurements if operated too close to a RA site. The RA site can be protected by physically controlling the area around the site. This is not generally practical since an area with a radius of 10 to 30 Km would need to be controlled. Alternatively, signs could be posted warning users not to turn on their mobile equipment within the protection zone radius. This may be unacceptable since the users may not see the signs or could avoid this control by simply ignoring the warnings.