M2Z, major supporters of a "porn-free wireless broadband access for all" plan, have rebuffed T-Mobile's spectrum tests that say it would interfere with the company's cellular signal.

The 2155-2175 MHz band (termed advanced wireless service, or AWS) has been the subject of contention for several years, as chunks of spectrum are the one of the most important commodities for telecommunications operations, and different groups want it used for different purposes.

T-Mobile spent $4.18 billion on 120 licenses (PDF from the FCC available here) to the AWS-1 band at the Federal Communications Commission's auction in August 2006. Verizon Wireless bid $2.8 billion and obtained 13 regional licenses, and Spectrum Co. (Sprint) obtained 48 licenses for $2.4 billion. The auction meant far more to T-Mobile than other wireless carriers because the additional spectrum facilitated the company's overdue 3G network.

Before the auction, a coalition called M2Z Networks presented a proposal to the FCC for the creation of a pornography-free and cost-free wireless broadband network based on a neighboring portion of the spectrum. Following the allocation of the spectrum, the FCC began considering a proposal for a 25 MHz section of the AWS-3 spectrum to be used for this purpose.

T-Mobile contested, however, that this would cause interference with AWS-1 devices, and filed an Interference Protection Proposal. In a presentation to the FCC last week, T-Mobile said that as much as one fifth of the spectrum experienced a 10% or greater signal reduction from Internet activity in the AWS-3 channel in its tests.

M2Z performed its own tests, and yesterday released its summary. That summary says that T-Mobile's results may have shown that AWS-3 interferes with AWS-1, but at the levels they tested (-105 dBm), it would draw interference from anything from Wi-Fi routers to microwaves and Bluetooth devices. M2Z contests that T-Mobile intentionally tested interference at a "breakpoint" that did not reflect normal conditions.