CCTV’s Eye-in-the Sky

HD wireless transmission systems are playing an important role in China’s upcoming coverage of the 2008 Beijing Summer Games.
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HD wireless transmission systems are playing an important role in China’s upcoming coverage of the 2008 Beijing Summer Games.


(click thumbnail)A specially outfitted Agusta A109 helicopter is being used for CCTV's coverage of the Games.The Chinese national broadcaster, CCTV, has chosen Nucomm’s HD microwave transmission systems to help provide live domestic coverage of the Summer Olympics’ opening ceremonies, and selected road-based events during the Games. To do this, Nucomm transmission equipment is being deployed on motorcycles and a specially outfitted Agusta A109 helicopter, so that up to three live HD feeds can be relayed to CCTV receive sites at any one time.

Motorcycles and helicopters
“There will be two cameraman-carrying motorcycles on the road, each one fitted with a Nucomm CamPac 2 HD/SD COFDM microwave transmitter,” said Simon Clifford, Nucomm’s director of international sales. When operated in HD mode, the CamPac 2 can provide data rates up to 50 Mbps using COFDM modulation and with a choice of single or dual carriers (‘pedestals’). Its signal will be boosted using a Nucomm GoPac 2 COFDM amplifier. The GoPac 2 is available in either the 2 or 7 GHz band, and can pump out 5 watts of signal.

The motorcycle signals will be received by the Agusta helicopter overhead, which also has its own Flir HD camera pod onboard. It has been fitted with two Nucomm Newscaster ‘Diversity 2’ microwave receivers. The Newscaster ‘Diversity 2’ is COFDM DVB-T compliant for 6, 7 and 8 MHz, and offers dual or quad maximum ratio combining, plus dual ASI/video outputs.


(click thumbnail)The copter’s passenger compartment holds three Campac 2 HD/SD COFDM microwave transmitters.“The Newscasters are being fed by four-way quad helix antennas on the belly of the aircraft,” said Clifford. “To get the received signals to the ground, we have three Campac 2s on board feeding a custom designed amplifier; all in a purpose-built rack in the Agusta’s passenger compartment. These three RF signals are combined and fed to a SkyLink polarized auto-tracking antenna.”

Where practical, the motorcycles will feed signals directly into terrestrial receive sites as well.

Nucomm’s sale to CCTV was the result of a “two-pronged attack’ by the company’s Chinese distributor and their parent company’s (Vitec’s) Beijing office. Clifford himself has a long history with China: “I worked on CCTV’s first analogue heli-system commissioned for the handover of Hong Kong in 1997,” he said. The 2008 Olympic system is the most complex he has ever worked on. “In fact, I know of no other three-channel airborne HD microwave platform in operation,” said Clifford.

At press time, Nucomm’s motorcycle/helicopter microwave system was destined to be used by CCTV to cover the Olympic Torch relay domestically. Once the Games begin, the platform will cover the opening ceremonies, then provide ‘beauty’ and fill-in shots for CCTV’s domestic Olympic broadcasts.


(click thumbnail)French OB company SFP is using a BMS cellular network to cover the Games.SFP using cellular network
In another Olympic RF development, French OB production company SFP is using Broadcast Microwave Services (BMS) cellular network technology to cover the Games. The theory of this approach is simple: Instead of using a helicopter or other dedicated platform, BMS cellular technology relays video signals through a series of dedicated ground-based receivers, all of which are connected to the master decoder by cable, fibre, Ethernet or point-to-point radio. The signals are managed by a BMS TS 4020/8020 ASI diversity switch, which ensures that the best quality signal is constantly fed to the OB van.

According to a statement released by SFP, “The whole system can be comfortably put up in four hours thereby offering a very inexpensive solution compared to a helicopter setup. The ASI diversity switching was seamless and completely invisible.”

The various wireless deployments surrounding the 2008 Summer Games demonstrate how important such technology is for major sporting events—live shots from a copter have become crucial for covering road cycling and marathon runs, in particular.