Trucker TV - New Threat to 2 GHz ENG Band
March 29, 2005
If potential interference from Department of Defense uplinks wasn't enough, users of the 2 GHz ENG band now have something else to worry about. Clarity Broadcasting Systems has filed an application for an experimental license to test a new "ultra-low power, short-range multichannel video distribution system." It would use 14 6-MHz wide channels covering the entire 2 GHz broadcast auxiliary service (BAS) band. While Clarity's description calls it "ultra-low power," a close look at the application shows it would use a horizontally polarized omnidirectional antenna with an effective isotropic radiated power (EIRP) of 10 watts per 6-MHz channel to deliver TV programming to stationary vehicles such as trucks and recreational vehicles located within 0.7 km of one of its transmitters.
The experimental license application is for facilities at Frazier Park north of Los Angeles--nearby Frazier Peak is an ENG site often used for covering traffic problems where Interstate 5 passes over the mountain (the "Grapevine")--and in Salt Lake City at Exit 28 (Redwood Road) off of Interstate 215. According to the application, Clarity "will soon be seeking permanent Commission authorization for more than 250 transmission systems of the design it proposes in the instant application." According to Clarity, none of the planned sites will interfere with Government Department of Defense operations. "As a result of this experimental program, Clarity will be able to demonstrate that its system does not cause harmful interference to any licensed users of the 2025-2109 MHz band, and will be technically and economically viable," according to Clarity. Nowhere in the application or attachment did I see any method for dealing with interference to broadcast operations in the 2 GHz band, other than Clarity's certification that they will protect licensed users of the spectrum from interference. Unfortunately, the continuing cases of interference from Broadband over Power Line (BPL) systems to licensed radio services indicates this may offer little protection to TV station ENG operations. If you want more information on the application, you will need to search for it by using the FCC Experimental Licensing System Generic Search page and entering the word "Clarity" in the box for "Applicant Name" (third from the top). No other entries are needed. Click the "start search" button and you will be taken to a page with links to the application and exhibits. The application was received March 2, 2005 and is still pending. Thanks to Howard Fine at Pacific Television Center for alerting me to this filing.
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