New Visible Light Communications Platform That Uses LEDs
The Visilink solution uses light photons to transmit signals over the open air to receivers. The signals are modulated upon transmission and then demodulated at the receiver for use by an end user device, such as a laptop computer, smart phone or networking server. The Visilink technology uses the blue portion part of electromagnetic spectrum which has the high relative output power even in quasi-white LEDs and therefore makes the best medium for data transmission in VLC-based systems.
For general network conductivity in buildings, Visilink uses quasi-white LEDs or RGB LEDs as transmitters. LEDs, unlike fluorescent and incandescent lights, can be modulated in such a way that the changing power output is not visible to the human eye. In RGB LEDs, any or all of the three separate LEDs can be used to send a signal. Visilink receivers are capable of detecting and then converting the optical transmission into a formatted data stream. Visilink receiver modules enable standard networking protocol such as Ethernet.
Visilink can provide network access through non-traditional environments as well, including electronic signage and computer/television displays. VLC wireless signals can't penetrate walls or other structures, making access local and extremely secure. Visilink technology can operate in environments such as hospitals, precision factories and mines where electromagnetic interference (EMI) prohibits the use of RF technology. Visilink can also eliminate the need to install wired networks by using existing power lines for communications (PLC).
"Up until now, networking has relied on RF technologies to provide wireless connectivity that can be limited in terms of electromagnetic environment and bandwidth," said Fumitaka Murayama, Chief Executive Officer of Outstanding Technology Corporation. "The fact that the Visilink technology can be used in all environments where LEDs are used warrants serious consideration for the next generation communications platform."
Visilink technology has achieved several significant milestones relating to speed and distance for visible light communications since it was first introduced in Japan in 2009. A transmission link using VLC was established at a distance of over 42 kilometers using a single 10W LED. In addition, the technology has demonstrated data transmission rates at over 160Mbps using a single LED, which is believed to be a record for interactive visible light data transmission connecting to the Ethernet.
The Visilink technology is available now for early customer evaluation in three product offerings. The first product, a Low Electrostatic Capacity Reflection Photo Detector LEC-RP0508, receives spatially visible light on which is superimposed a high-speed communication signal. The Visual Light Transmitter Module LEC-RL DV1ch-L contains a miniaturized reflective light-concentration LED (LEC-RL), a highly efficient broadband amplifier and a LED driver. The third product is a Visual Light Receiver Module LEC-RP SM1C-L, which includes a miniaturized, highly sensitive light-receiving acceptor (LEC-RP) and a high-broadband amplifier. Production-level models are planned for later in 2012.
Visilink VLC products work in combination with a MODEM to complete a communication system. MODEMs need to be selected according to the transmitted contents. MODEMs are also planned to be released later in 2012 on a case by case basis.