WRC-2007 Proposal Could Limit Emissions in Several Microwave Bands

One of the topics being addressed at the 2007 World Radiocommunication Conference (WRC-2007) is protection of the Earth-exploration satellite service (passive) from unwanted emissions in several microwave bands, including 1,350-1400 MHz, 1427-1452 MHz, 22.55-23.55 GHz, 30-31.3 GHz, 47.2-50.2 GHz and 50.4-52.6 GHz. In the United States, these bands are allocated for several radio services, including Part 25 (Satellite Communication), Part 27 (Miscellaneous Wireless Communications Services), Part 87 (Aviation), Part 90 (Private Land Mobile Radio), Part 95 (Personal Radio Services), and Part 101 (Fixed Microwave Services).

A proposal from the executive branch agencies includes specific, mandatory limits on unwanted emissions for transmitters in portions of the bands listed above. The FCC is seeking comments as to the impact of the proposed limits in terms of performance, cost, weight, size, and the like on systems in the specified frequency bands. Also sought are comments concerning the possibility that the systems could operate without significant modifications to current system design within the limits proposed in the executive branch agencies' proposal.

The FCC also wanted to know if the differences between these limits and the limits in the FCC rules are "significant enough to have an impact on the provision of current and future service applications in the affected bands?"

The Part 101 frequencies in the executive branch agencies proposal are 31-31.3 GHz and 51.4-52.6 GHz. Part 25 frequencies include 22.55-23.55 GHz, allocated for intersatellite communication, 50.4-51.4 GHz, 47.2-50.2 GHz (Regions 2 and 3) and 49.44-50.2 GHz (Region 1).

For details on the U.S. position on this WRC-2007 item, including proposed emission levels, see Public Notice (DA 06-2262). There are several attachments with the notice that contain the preliminary proposals for WRC-07 Agenda Item 1.20 developed by the executive branch agencies.