PARIS — T he epicenter of the scramble for access to C-band radio spectrum — a battle that is pitting satellite operators and cable-television distributors against broadband-wireless companies all over the world — has shifted to India following a ruling by Indian regulators against satellite users of C-band.

Any hope among satellite C-band proponents that quiet persuasion was making their case was dealt a blow by India’s Ministry of Communications, which has refused to rescind an order that, in effect, forces satellite-system users to vacate C-band by March 1.

The order, issued Jan. 19, warns satellite C-band users in the upper end of the band — 3.7-4.2 gigahertz — that their rights to that spectrum will disappear in favor of broadband wireless users, including WiMax systems. “All concerned users are advised to shift their operations to other suitable bands within six weeks,” the order says. After that, it says, “interference would have to be accepted.”

For satellite systems, the problem with the Indian order — and similar rulings made in South America and elsewhere in Asia — is that it appears to disregard the fact that any broadband wireless access to a portion of the C-band spectrum will wipe out satellite reception not only there, but everywhere else in C-band.

“Some governments have used this as an excuse,” said Kalpak Gude, vice president of regulatory affairs at Intelsat, the world’s largest satellite-fleet operator. Gude said it was unclear whether government agencies issuing the rules do not know of the consequences or have chosen to ignore them.

The situation is no clearer in India, a nation whose domestic satellite system includes C-band payloads aboard the Insat 2 series of satellites. The Indian Space Research Organis ation (ISRO) develops India’s domestic satellites and was blindsided by the Ministry of Communications’ move.

“Our operations are going to be affected and we are fighting it,” ISRO Deputy Director Suresh Kibe said in a March 1 interview. “We have asked them not to go ahead if there is interference. We have asked the Department of Telecommunications to first check it out.” The Department of Telecommunications is part of India’s Ministry of Communications and Information Technology.

Gude said there is unanimous agreement among those who have tested broadband-wireless transmitters located within 30 to 50 kilometers of a C-band receive-only satellite antenna that the entire C-band satellite link — from 3.4 to 4.2 gigahertz — is wiped out.

Gude said one problem in the debate is that governments are not aware of how many C-band satellite antennas are installed on their territories. In the United States, where C-band is of lesser relative importance than it is in high-rainfall areas in Asia, there are an estimated 11,000 antennas.

In the United States and elsewhere, C-band antennas deliver television signals to cable head-ends and on to consumers, multiplying the impact of any interference.

In an example that satellite operators use as a caution to regulators worldwide, Intelsat General Counsel Phillip L. Spector said the Bolivian government’s decision to permit broadband wireless use in a portion of C-band in 2006 knocked out many Bolivian televisions just before the World Cup soccer tournament was to begin. On seeing the consequences that a large segment of the population would not be able to watch the enormously popular event, Bolivian regulatory authority suspended their earlier authorization.

Peter Jackson, chief executive of AsiaSat of Hong Kong, a commercial satellite-fleet operator, said operating a WiFi or other broadband wireless access system anywhere near a C-band antenna “would be like standing next to a speaker at a Rolling Stones concert while trying to hear what someone 20 feet [6 meters] away is saying.”

Jackson estimated that in India alone, millions of homes will lose their television signal because their cable systems receive the broadcast signals from C-band antennas.

AsiaSat Engineering Manager Barry Turner said March 1 that other governments in Asia — including Pakistan, Japan, South Korea, Australia and Fiji — are in various stages of authorizing broadband wireless in one or another portion of the C-band.

Romain Bausch, chief executive of SES Global, the world’s second-largest commercial satellite fleet operator — and one that is actively pursuing the Indian market through its SES New Skies subsidiary — said Feb. 20 that SES Global has organized meetings with West African telecommunications operators to warn them against any moves in their nations to approve a C-band allocation for broadband wireless transmitters.

The issue is almost certain to be one of the most contentious at the next World Radiocommunication Conference (WRC), scheduled for Oct. 22 through Nov. 16 in Geneva. Quadrennial WRC meetings are held under the auspices of the International Telecommunication Union, a United Nations affiliate that coordinates thus use of radio spectrum around the world .

Governments that grant C-band use to broadband wireless operators are doing nothing illegal as they control matters in their territories. While part of C-band has been reserved at previous WRC meetings for satellite systems, a portion of it also has been allocated on a shared basis.

The problem, Jackson said, is that in this case, satellite systems cannot coexist with broadband wireless anywhere else in this portion of the spectrum. He said field tests by the Office of the Telecommunications Authority in Hong Kong confirmed that sharing is not feasible.

Intelsat’s Spector said the WRC conference, if not prepared carefully, may deliver a sobering message to cable-television and satellite networks of how small they are when matched against some of the biggest names in the communications industry.

The WiMax Forum, an industry association that promotes broadband wireless technology, is still studying the co-existence of satellite and broadband wireless users in C-band and has come to no conclusions about whether it is possible, Mo Shakuri, the WiMax Forum’s vice president of marketing, said March 2. “We think there are certain scenarios that could allow co-existence of the two services” in C-band, Sakuri said. “Combining with international and national guidelines, we are identifying the potential rules that allow coexistence and minimize the inter-service separation distances.”

At last count, the WiMax Forum had some 400 members including the biggest names in the telecommunications and technology sector.

Kibe of ISRO, asked why Indian regulators made their move without fully consulting the satellite sector, said there was a “big push” by industry, including Intel Corp., which wants access to the Indian market.