The ABC Owned TV Stations report early success with vehicles that rely on a combination of bonded-cellular and Ka-band satellite IP links. The group's Jim Casabella says used together the technology puts IP on par with point-to-point microwave.
ABC: Ka-band Making IP Newsgathering Work
The ABC Owned Television Stations may always maintain a fleet of conventional ENG microwave trucks, but it is beginning to replace at least some of them with a new breed of vehicles that relies on complementary bonded-cellular and Ka-band satellite IP links.
Jim Casabella, director of advanced engineering at the station group, says it is the Ka-band satellite connectivity that is making IP newsgathering practical. It puts IP on par with point-to-point microwave, he says.
“There is one Achilles’ heel of bonded-cellular technology,” says Casabella. “It works fine as long as there is bandwidth available, but particularly when it is a big story and there are a lot of people there, you can quickly overload the cell service and lose your story. It just goes away.”
Overlaying bonded-cellular with Ka-band satellite changes the equation, he says. “If somebody else comes up on your cell site and that bandwidth goes away, you are protected on the satellite. We are having great success with this approach.”
To the bonded IP encoder, Ka-band satellite signal looks like any other wireless bandwidth, says Casabella. If cellphone bandwidth availability degrades, there is more than enough available via the Ka-band satellite link. Conversely, if heavy rains cause the Ka-band signal to fade, cellphone circuits are available to maintain the feed, he says.
Bill Nardi, vice president, broadcast integration at Dejero, says the company’s bonded-cellular encoder needs little wireless bandwidth to protect Ka-band from rain fade.
“We require generally less than 1Mb/s of bandwidth to correct for any data packet loss that can occur on the Ka-band side, which can be caused by weather, low cloud cover and rain,” he says. “We basically have made those concerns a thing of the past.”
A new satellite modulation technique DVB-S2/ACM (adaptive coding modulation) also is helping to combat rain fade, says Bilal Awada, chief technology officer at C-Com Satellite Systems, a vendor of Ka-band dishes.
The six Ka-band-equipped IP trucks the ABC stations now have on the road can handle 10Mb/s upstream and 20Mb/s downstream to support everything from IP phone connectivity and IFB to hook ups with the station’s newsroom computer system, Casabella says.
While the station group has had early success with its Ka-band/bonded cellular trucks, it continues to rely on terrestrial microwave for more than half of its live field contribution, he says. “We have almost 100 microwave-only trucks. That is still our bread and butter.”
However, stations in the group have noticed the success these new Ka-band vehicles are having. “A number of our stations are now looking at it in their replacement cycle to phase in these trucks,” says Casabella.
Casabella began to testing the cellular/Ka-band combination using the ViaSat Ka-band service and Dejero bonded-cellular encoders in April 2013. Most of the six Ka-band trucks that have been put on the road since then are equipped with 1.2-meter antennas from AVL, says Casabella. “We also have at least one truck using the 75-centimeter C-Com dish, and that seems to work fine, too.”
Retrofitting existing ENG trucks with the technology is also under consideration. The idea is to replace pneumatic masts from existing ENG trucks with a stub that has a Ka-band satellite antenna attached, says Casabella.
“We are a very autonomous organization, so the decision gets made at every station individually,” explains Casabella. “But it is certainly something we are discussing, and as one station starts to do it, others will pick up on it.”
This type of retrofit offers the stations several advantages, says Casabella. It significantly reduces the weight of an ENG vehicle, which translates into reduced fuel consumption and operational savings, he says. Even greater savings can be realized when new V6 vehicles replace existing V8 and V10 ENG trucks, he adds.
“When coupled with bonded-cellular, Ka-band satellite gives broadcasters a two-pronged approach to broadband that allows smaller, more mobile and fuel-efficient trucks,” says Tony Wilkey, vice president of sales and marketing at Ka-band antenna vendor AVL.
Eliminating the mast also removes the danger of accidentally elevating it into power lines or driving down the road with it extended. Over the years, these types of errors have led to property damage, injury and even death.
When compared to the IP-over-Ku-band alternative, Ka-band also offers important advantages, says Casabella. Ka-band terminals cost about one-third the price of comparable IP-over-Ku-band equipment, and the cost of Ka-band bandwidth is about 30% less than Ku-band, he says.
Bandwidth availability also is better. “With Ka-band, we don’t have to schedule anything because there is so much availability,” he says. Using Ka-band for a link is as simple as it is to make a cellphone call, says Casabella. “You bring it, up, and it’s just there.”
Casabella foresees that as Ka-band grows in popularity and usage, scheduling bandwidth will become necessary as it has with Ku-band.
The Ka-band vehicles use the same automated set-top software that the Ku-band do, Casabella says. “We have 32 automated Ku-satellite trucks, and I have over 50 satellite trucks in total. None of them have satellite truck operators across our eight stations. They all are operated by photographers,” he says.
The addition of Ka-band technology has brought about a profound shift in the way Casabella thinks about IP newsgathering, he says. “There are two kinds of products,” explains Casabella. “There’s ‘in addition to,’ and there is ‘instead of.’”
When bonded cellular first came to market, Casabella mentally classified it as “in addition to” because there was no guaranteed quality of service, he says.
“You couldn’t guarantee that first story in the A segment of the 6 o’clock news was going to make it. But with the addition of Ka-band, I think it has now moved into the “instead of” category,” he says.
“Ninety-nine percent of the time, it’s going to get the job done.”