FCC: AWS-3 band won't interfere with T-Mobile's WCDMA network

Much to the chagrin of T-Mobile, FCC's Office of Engineering has tentatively concluded that services operating in the proposed AWS-3 band can co-exist with T-Mobile's WCDMA network that uses the adjacent AWS-1 band "without a significant risk of harmful interference."

Last month, the FCC sent its engineers to Seattle to conduct tests to determine whether interference would be a problem between the two bands. The FCC is keen on auctioning the 2155-2180 MHz band to support a nationwide license. The commission's ambition is to require the licensee to dedicate 25 percent of its network capacity to free broadband service and allow open access to third-party devices and applications.

T-Mobile has been adamantly opposed to the plan, citing interference concerns. M2Z, which has been lobbying the FCC for years to open up the band, has been submitting filings saying T-Mobile's assertions are wrong. The FCC published the raw data from the study Sept. 12 but refrained from interpreting the results as it continues with the AWS-3 rulemaking proceeding. T-Mobile was pushing the FCC to release those results.

The FCC said it conducted the same tests conducted by Optimi Corp. on behalf of T-Mobile. The results of that study, T-Mobile said, show AWS-3 services cause harmful interference to mobile devices in the AWS-1 band.  AT&T, CTIA, MetroPCS and Nokia Siemens Networks have concurred with T-Mobile that the tests proved interference.

The FCC's tentative conclusion certainly won't be the last word on the subject. T-Mobile has continually reminded the FCC that it has a legal obligation to protect AWS-1 licensees. The FCC acknowledged in its report that the FCC "has in the past adopted less stringent [out-of-band-emissions] standards under flexible service rules whereby the licensees and industry work together cooperatively to manage potential interference."

For more:
- check out the FCC's report

Related articles:
T-Mobile asks FCC to explain AWS-3 test results
AWS-3 spectrum debate festers 
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T-Mobile, others say tests proved interference
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