4k Video Wirelessly Transmitted in Real Time

2014/07/16 12:53
Motoyuki Oishi, Nikkei Monozukuri
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Ltec Corp exhibited a system that can wirelessly transmit and receive 4k video in real time at the 1st Live Entertainment & Event Expo (LIVENT), which took place from July 9 to 11, 2014, in Tokyo.

The company developed the system, "4k60p Wireless Transmission System," in collaboration with Techno Mathematical Co Ltd (TMC), Hitachi Kokusai Electric Inc, etc. It is expected to be used for live video streaming of events and concerts, digital signage, etc.

Recently, 4k cameras capable of shooting 4k video, etc are being brought to the market one after the other. But, in many cases, videos shot by those cameras are extracted by using removable recording media or via cables because it is difficult to ensure enough speed with wireless transmission.

"The 4k60p Wireless Transmission System can wirelessly transmit and receive high-resolution 4k video data in real time," Techno Mathematical said. "Though some other wireless transmission systems have already been proposed, they cause a long lag in transmission, making it difficult to call them real-time systems."

The 4k60p Wireless Transmission System has a simple structure consisting of an encoder, decoder, wireless transceiver and 4k display. This time, in a demonstration, Ltec input the source of 4k video into the encoder to encode it, transmitted it over a distance of about 5m with the wireless transceiver, decoded it with the decoder and displayed it on the 4k display.

The encoder and decoder are TMC's "TM5184MJC," and the wireless transceiver is Hitachi Kokusai Electric's "Sinelink FX" wireless data communication system using the 25GHz band.

The specifications of the new wireless transmission system are as follows.

Pixel count: 3,840 x 2,160
Frame rate: 60fps
Input/output interface: DVI (video input and monitor output)
Video compression method: H.264
Transmission delay time: 100ms (encoder and decoder) + delay caused by transmission path
Wireless transmission rate: 95Mbps (3,840 x 2,160/60fps)
Wireless frequency: 25GHz band