LiveU recommends keeping the backpack off the ground.
SEATTLE—Cellular live-shot systems have, in just a few years, become all the rage in the television news world. While news crews learn-while-they-earn in the field with live-shot units, the cellular live-shot system makers have chimed in with some universal tips on gaining more success with cellular video transmission.
Mike Savello, vice president of sales at LiveU in Hackensack, N.J., said live-shot crews in the field could use some lessons in RF basics.
“The very first thing some news crews do is to go to a live-shot location and place the backpack on the ground,” he said. “The problem is that cellular connection is not great on the ground. Worse yet, they’ll put the backpack on the ground with the antennas actually facing toward the ground. That is the worst thing you can do.”
Elevating the backpack, and therefore its antennas, is the best thing, he said. “If you can put it on the roof of a vehicle, or up in a tree, anything you can do to even get it higher than normal cellphone level, like a little higher than say five or six feet off the ground, it’s going to give you much better access to the cell towers and the signals that you need to get a good strong signal.”
Teradek’s bonded cellular system is built around the company’s economical and small CUBE H.264 encoder. LiveU’s Xtender external antenna solution can be connected to company’s other backpack and handheld units, offering even greater resiliency, performance and flexibility in crowded demonstrations, sports stadiums and other extreme scenarios.
KEEP A LOG
Joe Giardina, chief technology officer for DSI RF Systems in Somerset, N.J., pointed out a reality to keep in mind about cellular live shots: “Even if you have a cellular solution, that’s not the panacea of electronic newsgathering. There are still limitations of physics and cellular infrastructure.” He said that wise cellular system users are logging where they’re having successful live links, and updating them as the cellular infrastructure improves.
Giardina said DSI’s cellular solution relies on a single cellular modem, albeit on an industrial “that can pound nearby cellular towers with the strongest possible signal.” It defaults to DSI’s Breaking News Mode, which establishes a 256K link. That setting can then be optimized by the operator back at the station.
Dan Sørensen, marketing communications manager for TVU Networks in Mountain View, Calif. suggested customers evaluate and the identify priorities and then test equipment to make sure it fits the criteria.
“Are they able to seamlessly integrate with multiple transmission technologies, whether that be 3G and 4G cell cards, or WiFi, or internet, or Ka satellite, or wireless, or whatever they be?” Sørensen asked. “Can they seamlessly move between those transmissions without interruption?”
The company’s TVUPack provides dual encoders which allow it to not only feed the audio and video live via the cellular network system, but also record HD onto a hard drive in the backpack for later transmission to the station should conditions degrade during a live shot.
THE LATENCY ISSUE
Bogdan Frusina, chief technology officer for Dejero in Kitchener, Ontario, brought up one of the banes of live shots: latency. Delay as the signal is coded, IP-transmitted and then decoded can lead to uncomfortable seconds passing between when the news anchors introduce a live shot and when the in-the-field reporter begins speaking in the newscast.
The tradeoff is that when latency is reduced, signal quality can be compromised. Dejero has built into its cellular system an “Adaptive Latency mode, where you can dial in the amount of latency you can live with.” The system automates the adjustment of the video to provide no more than the latency limit that’s set. That can be overridden should video degrade beyond an acceptable point.
Chris Crump, director of sales and marketing at Devens, Mass.-based Comrex, pointed out that it’s not always possible to do a site survey of an area where the ENG crew is going to go live. “But if you have a general idea about the cellular coverage in the area where you’re going to be operating, you’re more likely to have success,” he said.
He added that cellular coverage maps from the carriers are something a news crew can carry around so they can familiarize themselves with the local dominant carrier. “I generally carry around AT&T, Verizon and Sprint modems so I can take advantage of the strongest signal in that area,” Crump said.
Comrex’s Liveshot cellular system is designed with mounts to allow it to fit between camcorder and battery to eliminate the backpack.
John Payne, vice president of Engineering with IMT in Mt. Olive Township, N.J., says ENG crews should have a backup plan. “As the breaking news story goes on and the cellular circuits get more congested, it’s important to have other paths back to the station,” he said. While that can consist of individual pieces of cellular system and microwave equipment, a hybrid system can simplify the operation.
IMT has developed the Connect Live hybrid system with Dejero that allows connecting into the Dejero server at the TV station and integrated into the Dejero web portal. “We provide a bonded cellular product that connects into their system, but also has a COFDM or a microwave transmitter integrated,” Payne said. Connect Live can also feed a satellite truck via Ethernet.
Light and Fast
Jaqueline Roy, vice president of marketing for Vislink in N. Billerica, Mass., said that to best take advantage of cellular transmission’s portability, you want to be able to be able to work fast without extra pieces of gear. As an example, she pointed to coverage of the World Series victory parade for the Boston Red Sox last fall.
“In the middle of all the action and news crews was a camera mounted with our Air- Cam Max transmitting its coverage of the event,” she said. The team was set up and streaming within five minutes of arrival, walking through the crowds chatting with attendees during the event, all while transmitting live, HD quality video back to the station.
AirCam Max uses Vislink’s proprietary bonding algorithm, with the option to seamlessly transition to microwave transmission to avoid any gaps in coverage.
Dave Walton, assistant vice president for marketing communications at JVC, pointed to a more “bang-for-the-buck” cellular solution to help news directors get more live-shot-capable camera units in the field. “As cellular providers are building out their LTE systems very rapidly, some of the things that used to be required for cellular live shots are no longer necessary in many locations,” he said.
He referred to the lower bandwidth 3G and down cellular systems that required bonding of several cellular modems in order to achieve quality video transmission on a live shot. JVC’s GY-HM650 ProHD camera utilizes an internal encoder to deliver a live-shot-ready stream to an LTE modem plugged into the camera body. “Every cameraman can carry an individual modem with the 650, and be live-shot ready.”
Jon Landman, vice president of sales for Teradek in Irvine, Calif., suggested that cellular video transmission systems have potential uses that go beyond getting news liveshots back from the field.
“You think someone’s going to give you and Ethernet drop and everything’s going to be perfect, and that’s not always the case,” he said. “So a cellular transmission system becomes a redundancy system, not just a news solution.”
He said Teradek’s bonded cellular system, built around the company’s economical and small CUBE H.264 encoder, was ideal for this use.