The U.S. Federal Communications Commission may gather enough data through wireless testing this week in Seattle to quiet debates over the potential interference that could result from a proposed spectrum auction.

The FCC has proposed auctioning off spectrum and requiring the winner to offer free wireless broadband services in a portion of the spectrum. But the wireless industry contends that the technical rules that the FCC is proposing for the spectrum will lead to interference for 3G (third-generation) phone users, causing a degradation of their services.

T-Mobile, one of the more vocal opponents of the FCC plan, has already conducted tests that it says clearly demonstrate the harmful interference. "But what we've been asking for is joint testing with the FCC," said Kathleen Hamm, vice president of federal regulatory affairs for T-Mobile.

The FCC is conducting some of the same tests T-Mobile has already done plus some additional tests, focusing on interference between handsets running on the different frequencies, said Julius Knapp, chief for the FCC's office of engineering technology.

Some of the tests that the FCC is repeating involve using handsets connected to WiMax or UMTS (Universal Mobile Telecommunications Systems) networks running on spectrum the commercial providers would use and then issuing signals using the proposed new service and spectrum. The engineers note at what signal strength the proposed service causes the WiMax or UMTS call to drop or prevents the calls from even connecting. "That's where views differ," Knapp said.

In addition, the FCC is testing how filter technologies deployed on the handsets might work to mitigate some of the interference from the proposed service, another hotly debated issue, Knapp said.

After the testing is complete, potentially at the end of the day Thursday or on Friday, the FCC will issue a report with its findings. The commission may or may not officially ask for comments on the report, Knapp said. "But we're confident people will weigh in on what it means," he said.

In addition to T-Mobile and FCC representatives, engineers from AT&T, M2Z Networks, Nokia, Metro PCS, CTIA and XM Sirius are attending the testing, which is taking place at a Boeing facility in Seattle.

M2Z was one of the first companies to propose that the FCC distribute the debated spectrum for wireless use. The company contends that many tests into potential interference conducted around the globe have proved that operations in the spectrum wouldn't cause undue interference to nearby services. In some other countries, operators have already been allowed to offer services on the basis of those tests.