Interfering Signal: Operators, Partners Take Industry Approach to Tackle Interference

Eutelsat’s announcement in September to implement Carrier ID in video transmissions for the 2012 Olympics could prove to be a key moment in the battle against satellite interference. With satellite operators losing millions of dollars each year due to interference, new initiatives and solutions to counter this growing problem are in high demand.

Satellite interference, whether in the form of a lost TV video transmission, an incomplete credit card authorization or potentially any form of satellite service interruption, continues to occur with increasing frequency. Human error is a major cause of interference, followed closely by poorly performing equipment. “The largest culprit we see is the untrained or undertrained installer or operator,” says Ron Busch, vice president, Network Operations, Intelsat. “With two-degree spacing, it’s becoming more and more prevalent around the world.” In 2008, operators estimated that there were between 14,000 and 15,000 interference events a year, and of those, half were of too short a duration to track. A little more than half of the incidents that could be tracked were VSAT-related and due to installer error or bad equipment. Interference Costs Mount

The satellite operator community, while not providing specific numbers, acknowledges that losses from satellite interference are significant — in the millions annually. Three years ago, one operator stated that for every three satellites in its fleet, it lost $10 million per year.

“Every stage of the value chain of our industry is affected by this problem — not just the operators,” says David Hartshorn, secretary general, Global VSAT Forum (GVF). He notes that operators typically see it first, followed by the satellite operator’s customer and then the end-users, who may seek competing alternatives if they experience degraded quality of service. “We have the competitiveness of our industry on the line if we don’t get this right,” he adds.

While high-profile satellite customers such as network television broadcasters have found ways around interference by using back-up capacity or other fixes, “interference still represents a huge hit for your network in terms of reputation and reliability and the promise we have to our customers,” says Dick Tauber, vice president, Transmission Systems & New Technology, CNN News Group. “Media broadcasters don’t want 100 percent reliability; we want 110 percent reliability. There’s very little patience in this industry on the TV-side for interruption.”

When it comes to escalating satellite interference, Stewart Sanders, senior vice president, Customer Service Delivery, SES, contends that the technology advances and market factors have come together in such a way to create a “Perfect Storm.” These factors include the explosion in the number of VSATs and other satellite services worldwide; the availability of cheaper, more powerful equipment; less emphasis on type approvals for equipment; loss of the PTT-sponsored training and certification; and the industry adoption of two-degree orbital spacing.

“You put all those things together and it’s inevitable that we are going to have a lot more problems than we did 20 or 30 years ago,” says Sanders.

SES and Intelsat, the world’s largest satellite operators, have stepped up, responding in part to a growing chorus of customer concerns by bringing together 19 operators as part of an industry-wide effort to intensify the battle against interference. “If we don’t work on it together, I don’t know if we can ever solve the interference issue,” says Busch.

The companies’ decision to take action and the broader efforts by leading industry groups such as Global VSAT Forum and the Satellite Interference Reduction Group (sIRG), have led to significant milestones in the satellite interference battle. They include a new global industry standard to train and certify installers worldwide, the launch of numerous working groups to develop solutions, such as Carrier ID, and the establishment of the Space Data Association, to enable operators to share satellite position and other critical information.

The Global VSAT Forum leads two of the industry initiatives — installer training and product quality assurance. The forum’s installer training program has already reached about 4,000 installers and certified dozens of examiners, cutting by half the cost of training technicians in developing countries, says Hartshorn.

Hartshorn adds that number is only a “drop in the bucket” compared with the total population he needs to reach, which he estimates to be in the tens of thousands. Both Intelsat and SES have funded hundreds of trainees for their customers, and Arabsat, Hispamar and Star One have begun similar programs in their markets. Hartshorn believes that it is necessary for all installers to eventually be required to complete certification before they are permitted to work on earth station equipment. He adds that the program now is delivered online as well as through formal hands-on skills testing with certified examiners.

In Brazil, all five operators agreed to coordinate installer training in a model approach that GVF hopes to replicate in other regions. “We will do this country or regional market by market worldwide until we get the whole world. It’s not going to happen quickly but it’s going to happen,” he says. 

Carrier ID Could Help Eliminate Interference

According to Martin Coleman, sIRG executive director, a Carrier ID solution deployed industry-wide would translate to better efficiency. “Operators will be able to tackle problems quickly and get carriers sorted out because they know where the interference is coming from, who to call and the procedures for getting them down.” Coleman says with the right solution in place, resolving interference would go from taking an hour or weeks to minutes.

The wireless industry is angling for more than just wireless C-band. Everything is on the table down the road and we have to be extremely vigilant to protect continued access to those bands in a way that does not cause interference.
— David Hartshorn, secretary general, Global VSAT Forum

Coleman helped develop the industry’s first Carrier ID system in 2006 for video transmissions. Ratified in 2008 by the World Broadcasting Unions, the solution took a segment of the digital stream and inserted basic contact information and integrated it with a GPS system to get the latitude and longitude coordinates. However, that solution has limitations. Coleman explains that the ID was in the network interface table of a DVB-S2 carrier. That means it was in the video stream, meaning it could be destroyed by interference itself.

“For a permanent ID system, we needed a solution that enables operators to isolate the interference source at the modulator level, not in the stream,” says Coleman.

Eutelsat recently announced its commitment to have Carrier ID on all video transmissions for the 2012 Olympics, including all SNG transmissions and new DVB broadcasts — a move that other carriers are expected to follow soon.

“I think carrier ID would eliminate 80 percent of interference,” says Tauber, who serves as co-chair of the Radio Frequency Interference – End Users Initiative (RFI-EUI), a voluntary group formed in February and led by broadcasters. One of the three working groups established in RFI-EUI is focused on Carrier ID.

Two years ago, sIRG issued a requirements proposal to manufacturers outlining three criteria for Carrier ID: that the solution could be readable even if it sat on a carrier with encryption or conditional access; that the technology used a format that was universally accepted across the industry; and that the embedding would have no effect on the carrier’s network or on carrier transmissions.

In mid-October, Comtech EF Data began offering a Carrier ID solution to commercial customers that has encoding in the modulator. The company offers both a firmware and an external box for modulators that are five years old or older.

“We came up with an approach that meets all those requirements. It doesn’t matter whose device, as long as it is a static carrier — a video or SPCP — this technology will work,” says Fred Morris, vice president, Sales Engineering, Comtech EF Data. He adds that the response has been encouraging by operators that have tested it. “There has not been any other alternative that’s been presented that meets the requirements. The momentum is picking up on this, and it’s picking up at a pretty rapid clip,” he says.

Manufacturers such as Ericsson and Newtec have agreed to commonly standardize a solution for Carrier ID.

“We want an industry consensus on what should be implemented, and up until IBC that didn’t exist,” says Lisa Hobbs, vice president, Broadcast Compression Solutions, Ericsson. “It has now been agreed to take the Comtech solution through an industry standardization process with Ericsson’s support, plus the support of several other manufacturers and users, and we will support whatever final specification is approved.”

In September, CBS-TV completed a one-month trial of the solution on one of its full-time network distribution transponders to test the impact to reception at CBS’s Network Affiliates. When Via Satellite contacted the network in September, the trial was nearing completion with no impact to operations.

“The goal was to demonstrate that the Carrier ID signal can be used routinely with satellite uplinks without degrading the intended service. As a next step we would propose a field trial within a newsgathering operation, again to determine impact to routine operation,” explains David Chilson, associate director, Broadcast Distribution Services, CBS-TV. “If the technology proves adequate to the task, and if we obtain universal adoption for its use by satellite operators and users, we will have a powerful tool to identify and reduce the sources of interference,” he adds.

Coleman’s organization began establishing working groups in October that look at getting Comtech’s Carrier ID solution incorporated into the DVB specification, the first step in mandating Carrier ID on all modulators built. 

Technical Challenges

Carrier ID requires much greater data sharing by industry, and one option being considered is leveraging the infrastructure of the Space Data Association (SDA). Inmarsat, Intelsat and SES founded the SDA, and most recently Eutelsat joined as an executive member. Originally focused on avoiding satellite collisions, SDA currently performs Conjunction Assessment processing for 232 geosynchronous satellites (which is more than 65 percent of all operational geosynchronous satellites) and an additional 110 LEO and other orbits satellites.

Sanders, who is also SDA’s chairman and director, recalls that in the past, operators shared satellite location data on an “ad hoc” basis, and seldom in the same format. “The data flow wasn’t consistent. We needed to put a more formal footing with a legal framework so we could protect the value of the data and ensure it’s not misused. After much hard work and cooperation between competing companies, that’s exactly what we’ve done. That’s not the end of the story though, we will continue to expand the membership and develop the system and its scope of activities in support of a safer and more secure space and RF environment,” he says.

SDA recently opened its operational Space Data Center (SDC), the first global operator-led network for sharing high-accuracy operational data to improve overall space situational awareness and satellite operations. 

Issues on the Horizon

According to satellite officials, the next item to address on the satellite interference agenda will be the increasing problem of auto-acquiring antennas. “It’s our next priority,” says Coleman. “In addition, we’re looking at satellite ID so when a system points to a satellite, it actually knows which satellite it is pointing at.”

Hartshorn has his eyes set on the wireless industry’s push for frequency sharing. Frequency sharing — already in place for WiMAX services over C-band — has caused significant interference problems to date. According to Sanders, WiMAX operators are rolling out equipment without paying attention to the proximity of established earth stations. “It’s something we constantly have to look at,” he says.

Hartshorn notes that Qualcomm helped initiate an open proceeding at the U.S. Federal Communications Commission (FCC) calling for sharing Ku-band. Qualcomm is asking to use the frequency to deliver wireless services on aircraft.

“In nearly a dozen countries and in every region of the world, there are open proceedings looking at Ka-band frequency sharing,” says Hartshorn. “The wireless industry is angling for more than just wireless C-band. Everything is on the table down the road and we have to be extremely vigilant to protect continued access to those bands in a way that does not cause interference.”

The industry is calling for operators and users to engage with interference issues at all levels with better preventive measures and faster resolutions to problems as they occur. Tauber emphasizes that satellite interference can’t be stopped by Carrier ID. “The most important steps towards the goal to stop, or at best mitigate RFI, are requiring high industry standards of training, and the eventual certification of operators.” Hartshorn adds, “We need stronger support and a sense of resolve from the entire operator community to make this successful. We need to come back to requirements.”