PARIS — Global regulators ended the third week of their four-week conference on future radio spectrum allocation Nov. 20 without having reached a decision on the key issues relating to commercial satellite telecommunications industry.

As many predicted, decisions on whether satellite broadcasts will lose their exclusive use of the lower portion of the C-band spectrum to terrestrial broadband networks and face near-term battles over Ka-band spectrum by the same mobile broadband industry remained unsettled.

Also undecided was whether the fast-growing unmanned aerial vehicle (UAV) industry would be awarded access to Ku- or Ka-band spectrum for command and control of commercial UAVs over long routes.

Opposing parties on all three of these issues tended to take a glass-half-full approach in analyzing their prospects three weeks into the World Radiocommunication Conference, WRC-15, being held in Geneva Nov. 2-27.

For the commercial telecommunications satellite industry the most important issue is whether it will lose its exclusive access to C-band — and if so, how much of it will be lost.

The debate is over the swath of spectrum between 3.4 and 4.2 gigahertz. Satellite industry officials have said dozens of spacecraft deliver essential services in C-band, especially in Latin America, Africa and Asia, and that signals are too weak to survive the entry of terrestrial wireless broadband into the spectrum.

Going into the conference, organized by the International Telecommunications Union (ITU), a United Nations body, there appeared to be a growing consensus that the bottom 200 megahertz, 3.4-3.6, was slipping out of the grasp of the satellite operators, with a threat that terrestrial broadband might be allowed to cohabit the spectrum up to 3.7 or even 3.8 gigahertz.

The largest undecided bloc was Africa, whose national delegations appeared to be holding firm on keeping terrestrial broadband out of C-band above 3.6 gigahertz, but vacillating on 3.4-3.6 gigahertz. Asia and the Russia-centered Commonwealth of Independent States appeared to be solidly in the pro-satellite camp before the start of WRC-15.

With one week remaining at the conference, the correlation of forces has either changed dramatically or not at all — depending on who makes the assessment.

The 170-member U.S. delegation favors allowing terrestrial broadband into the 3.4-3.6-gigahertz spectrum, and perhaps as high as 3.7 gigahertz, but has said it would fight any attempt at an incursion any higher in the band.

Decker Anstrom, head of the U.S. delegation, said Nov. 19 that the full “No Change” position pushed by satellite fleet operators has lost most of its support. “There is a clear global consensus” on allowing terrestrial broadband into the lower portion of C-band, Anstrom said at a press briefing. “While there are some ‘Nos’, those voices are not very loud.”

The Global VSAT Forum (GVF), a satellite industry lobbying group, has a different view of the state of play at WRC-15.

“The positions of the various regions have not changed since the conference started,” GVF Secretary-General David Hartshorn said Nov. 19. “There are still voices raised, especially in Africa, against any change in the allocation. “And the RCC [the Commonwealth of Independent States] still wants no change in C-band.”

A second issue that has become a high priority for several governments, especially the United States and Germany, is allocating a portion of the commercial Ku- or Ka-band spectrum widely used by commercial satellite fleets for UAV command and control.

A draft ITU document published Nov. 16 summarized the common position of several dozen nations backing the UAV allocation as saying UAVs would be bound by the same no-interference constraints that now apply to satellite Earth stations, and would not be granted any special rights.

In addition, the pro-UAV position paper said, UAVs would need to meet the standards and recommended practices and procedures established by the International Civil Aeronautical Organization.

The document nonetheless listed regions and governments opposing the move, including Russia, Norway, the United Kingdom, Holland, Arab states and several Asian nations.

Anstrom said many nations without a strong opinion one way or another have adopted a pro-UAV stance at WRC-15 in recent days, even if they have not advertised the fact. But he said a final agreement likely would await the final days of the conference.

One industry official at WRC said Russia has insisted that more study be done before agreeing to the UAV proposal, and that the issue be put off until the 2019 WRC. This official said that because the United States has made it such a priority, last-minute negotiations with Russia and others likely would result in at least a partial pro-UAV decision at WRC-15.

Also to be decided is whether to formally allow studies to start on allowing terrestrial broadband into higher frequencies used or planned by satellite systems, including Ka-band. That issue is far from being settled, officials said.

Peter B. de Selding was the Paris bureau chief for SpaceNews.