War images now sent via satellite 'videophones' |
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Satellite videophones are being used by CNN and other major TV news stations to send back low resolution video of events in Afghanistan. The television images, invariably grainy and green, are being relayed by lunch-box-sized videophones over a portable satellite telephone using the Inmarsat satellite system parked 22,300 miles above the earth.
Without the $7,950 videophone, manufactured by London's 7E Communications Ltd., live video from remote places like Afghanistan requires a satellite uplink facility comprised of at least a ton of recording and broadcast gear, operated by a crew of three to four, usually housed inside a van. Videophones first grabbed attention in April, when a CNN reporter connected one to a car battery and broadcast live images of a U.S. spy plane crew departing China's Hainan island. The videophone allowed CNN to broadcast footage almost a half-hour earlier than rival broadcasters, who drove to an uplink facility to transmit their video. The 7E ‘Talking Head’ series video reporter units are rugged, portable and suitable for location work anywhere in the world where there is an ISDN line or a suitable Inmarsat terminal.
The system sends video and audio in both directions at the same time, so a reporter can not only hear the studio he/she can see the studio output too. Incidentally a mobile unit can be used at the studio and a rack mounted unit in the field, perhaps in an OB truck for reverse vision. Housed in a waterproof case and using tried and tested technology, the unit can be used in the harshest of environments with complete confidence. Simplicity and flexibility of operation for the lone reporter has been the keyword in the product’s development, resulting in a minimum of complex controls. The unit can be powered from the local mains source (90-264VAC), or a nominal 12V DC source, such as a BP-90A camera battery.
The system can either use one channel (line) of an ISDN-2 to operate at 64 kbps or by making two calls 128 kbps. The higher data rate allows the system to cope with more movement in the picture, or if desired improve the audio quality to studio standard (48 kbps rather than 16 kbps) in lieu of a smaller improvement in the picture quality.
Excellent picture quality at 64/128kbps is assured by the use of the latest H.263 compression algorithms, or if desired high quality (7.5kHz) audio and low speed pictures can be transmitted instead. A simple mixing facility on the unit enables low-Z microphones and balanced or an unbalanced line sources to be connected simultaneously. A custom designed I/O processor optimizes the audio/video for transmission, whilst providing both professional (XLR/BNC) and domestic (phono) connections. Headphone jack sockets provide both direct and cue (return) signals for monitoring purposes. An adjustable 6.4" TFT Colour display with speaker completes the package. Storage for cables, microphone, headphones is provided within the case so that the unit is totally self-contained.
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