Pay-radio operator SiriusXM has complained formally to the FCC that T-Mobile’s adoption of new terrestrial frequencies is corrupting SiriusXM’s own radio repeaters.

T-Mobile has started using additional frequencies it bought in the FCC-authorised AWS (Additional Wireless Spectrum-3) auctions. SiriusXM claims that the T-Mobile signals, plus its own transmissions, are resulting in a third signal created by ‘intermodulation’ of the two transmissions.

T-Mobile says that it is SiriusXM’s problem in that its car radio sets should be capable of filtering out this crosstalk.

SiriusXM, in its filing to the FCC, is blunt, and argues: “SiriusXM subscribers have recently begun experiencing harmful interference to their satellite radio reception in select large urban markets. This interference-which can be severe, completely blocking reception of the service-became noticeable only after T-Mobile deployed its AWS network in those markets. Through initial testing, SiriusXM identified T-Mobile AWS base stations as the primary contributors to this interference, because they produce extremely high power-density levels at the street level. These power-density levels are as much as 14 dB greater than those produced by other wireless carriers in AWS or any other spectrum bands used for mobile broadband service. Unless remedied, this interference problem will worsen as T-Mobile continues to implement its AWS network by constructing and activating facilities in additional markets, likely including facilities in the service areas and using the frequencies covered by the licences at issue in the Application.

Categories: Articles, Digital Radio, Policy, Regulation