| 摘要 |
<p>PROBLEM TO BE SOLVED: To increase an amount of information that can be transmitted while maintaining such a high-speed property of processing as to deal with movement by walking of a user of a mobile terminal, in a system for communicating information related to location to the portable terminal by a sound wave.SOLUTION: A plurality of ID transmitters each comprising means of outputting a sound wave signal consisting of a sine wave of one or more different frequencies, are installed at a distance so that respective ranges where the respective sound wave signals arrive are different from each other. With respect to the transmitted sound wave signal, a predetermined number of frequencies included in a frequency region utilizing an upper limit region of an audible frequency, correspond to a predetermined number of bits. A value of each bit is represented by presence or absence of an output of the sine wave of the corresponding frequency. Information to be communicated is divided into a plurality of pieces of partial information. Each partial information is represented by at least a part of the predetermined number of bits of the sound wave signal. The ID transmitter comprises means for switching the outputted sound wave signal every first predetermined time, and circulates and outputs the sound wave signal by which the partial information is represented, according to an order that the information is configured.</p> |
