The Satellite Industry Assn. (SIA) told the FCC last week it was ...

proposal on the use of 3650-3700 MHz for unlicensed uses (CD April 9 p8). The FCC in Nov. launched an inquiry on making additional spectrum available for unlicensed devices, including Wi-Fi, that can use frequency-agile radios to share spectrum with incumbents. The inquiry sought feedback on whether unlicensed devices should be able to operate in bands beyond those allowed under Part 15, including TV broadcast spectrum and at 3650-3700 MHz. The NOI sought comment on the feasibility of allowing unlicensed devices to operate in bands such as 3650-3700 MHz at power levels substantially higher than the maximum allowed in other bands, with technical requirements to avoid interference to licensed and incumbent services. The FCC has viewed such spectrum uses as particularly promising for underserved rural areas. The NPRM that’s on the Thurs. agenda addresses only the 3.6 GHz spectrum. An FCC source said that although the proposal doesn’t tee up broadcast spectrum issues, they simply aren’t being addressed in this item. SIA reiterated concerns in last week’s filing that 3650-3700 MHz is “a very important band for international satellite services because other countries use this portion of the global primary FSS [fixed satellite service] allocation. Existing use of the band is concentrated along the East and West Coast, comprising the most densely populated regions of the United States.” It said new earth stations, however, aren’t necessarily geographically limited. SIA said FSS operators already use the 3650-3700 MHz band extensively to provide international communications services and commercial and govt. communications. The licensing of new earth stations on a secondary basis must now be protected by unlicensed users, SIA said. “Subsequent deployment of earth stations in an area with unlicensed links may require the links to shut down,” SIA said. In other areas, it warned that adaptive frequency hopping to avoid interference may not work. SIA said that because there’s no standard uplink channel associated with a downlink channel, unlicensed devices don’t know where to “listen” before transmitting. “Receive-only earth stations, or earth stations with asymmetrical transmissions, may be subjected to interference because [there is] no transmit channel associated with receive frequencies,” SIA said.