In May 2007, the Commission released a Report and Order and Further Notice of Proposed Rulemaking adopting processing and service rules for the 17/24 GHz BSS. The Report and Orderand Further Notice of Proposed Rulemaking included a framework in which 17/24 GHz BSS space stations would operate at orbital locations spaced at 4.0º intervals, as set forth in Appendix F of the Order and FNPRM (known as Appendix F locations). Among the service rules adopted, the Commission established uplink earth station antenna performance standards, limits for uplink and downlink power levels to minimize the possibility of harmful interference, and stipulated criteria to facilitate sharing in the 24.75-25.25 GHz and 17.3-17.8 GHz bands.
The Further Notice of Proposed Rulemaking sought comment on coordination parameters relating to space path and ground path interference in the 17 GHz band. Space path interference arises when the downlinked signals transmitted by 17/24 GHz BSS space stations are received by the feeder link and/or telecommand antennas of nearby DBS space stations. The amount of space path interference received by the DBS space station will depend upon the specific orientation of, and separation between, the transmitting 17/24 GHz BSS space station and the receiving antenna on DBS space stations; the power level transmitted by the 17/24 GHz BSS space station; the off-axis gain discrimination characteristics of the transmitting antenna on the 17/24 GHz BSS space station; and the off-axis gain discrimination characteristics of the receiving antenna on the DBS space station.