Standard of Japan Electronics and Information Technology Industries Association

Visible Light Beacon SystemThis standard stipulates communication method of single directional visible light beacon
system based upon the communication method created by the Visible Light Communication
Standardization Project Group in Technical Standardization Committee on AV & IT Systemsof Japan Electronics and Information Technology Industries Association.
Visible light beacon system is a system for providing various applications such as
identification of matters, providing positional information, and establishment of various
guiding systems by radiation transmission of simple information or ID information unique tothe visible light source from visible light sources ubiquitously surrounding us. This standard
aims at establishment of a unified standard concerning lower communication layer common
to these applications to utilize it commonly, and do not deal with upper communication layer
which depends upon individual applications.
This standard prescribes the single directional communication system with visible light as
the medium (hereinafter referred to as visible light beacon system). It especially prescribes thestandard concerning IF-a (interface point a) part in the visible light beacon system in Fig. 1.
Visible lightbeacon
transmitter

IF-aVisible lightbeacon receiverFig. 1 Visible light beacon system
The visible light beacon transmitter can transmit ID. The ID code system used is selectable,and various services, for example, equipment identification, position information and datatransmission function can be provided. For equipment identification, the visible light beacon
transmitter transmits ID of target equipment (Serial number, etc., can be included.). The
receiver identifies equipment by ID resolution and can obtain information concerning theequipment. The information includes maker name, product name, specification sheet andmanual of the equipment, information of consumables, use history, etc. For positionalinformation, the visible light beacon transmitter transmits coded geographical information of
the place where the instrument is installed (positional information ID). The receiver canobtain its positional information by ID resolution. Detection of peripheral services based on
the present position, transmission position report function at the time of emergency report andso forth can be realized in buildings or underground malls where use of GPS is difficult.
Further, the function can be used as the means for a robot to detect its position. For datatransmission function, the frame structure of visible light beacon can have one or both of ID
and DATA in the information part (Payload). The visible light beacon transmitter can utilize
the DATA region to transmit optional data stream. For example, it can transmit texts which isthe common data form, if the receiver responses, data or commands for specific procedure orapplication.
Carrier frequency of this system shall be visible light of peak wave length of 380~780 nm.
Visible light is intensity modulated by 4PPM (Pulse Position Modulation) signals, of which
information data rate is 4.8 kb/s.
Frame structure is shown in Fig. 2.

The frame consists of start part (SOF), Payload, andend part (EOF). Further, SOF is divided into preamble (PRE) and Frame-type (F-TYPE), andinformation part consists of ID and/or DATA part. The EOF is cyclic redundancy check(CRC-16).
SOF(Start of Frame)PRE
F-TYPE(6-bit)(8-bit)PayloadID / DATA(128-bit)

EOF(End of Frame)
CRC-16(16-bit)Fig. 2 Frame structure
The PRE is encoded 4PPM signals, which does not occur by normal 4PPM encode of data, isset as the frame start position. In the F-TYPE, the codes indicating kinds of payload arerepresented by 8 bits in order to enable use of IDs and codes of different plural systems andtransmission of data. The Payload consists of 128 bits ID and/or data. CRC field length shallbe 16 bits. Reception side judges whether frame data were correctly received. Since visible
light beacon system is single directional communication incapable of re-transmission request,
received data are discarded if error was detected. Calculation results of CRC are stored in
CRC field. Calculation ranges of CRC are F-TYPE and Payload.