{
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  "description": "The ultrasonic sound guide system presents the audio broadcasting system based on the inaudible ultrasonic sound to assist the indoor and outdoor navigation of the visually impaired. The transmitters are placed at the point of interest to propagate the frequency modulated voice signal in ultrasonic…",
  "path": "/patents/1337207",
  "publishedAt": "2023-02-09T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "G09B21/006",
    "Kevin Saeyun Kim"
  ],
  "textContent": "The ultrasonic sound guide system presents the audio broadcasting system based on the inaudible ultrasonic sound to assist the indoor and outdoor navigation of the visually impaired. The transmitters are placed at the point of interest to propagate the frequency modulated voice signal in ultrasonic sound range. The receiver device is carried by the visually impaired in wearable device form to receive the ultrasonic sound for the voice signal via demodulation. Since the ultrasonic sound demonstrates the acoustic properties, the directivity, attenuation, and superposition of ultrasonic sound provide the acoustic clue to the receiver device user for localizing the transmitter positions. The visually impaired hear the designated voice signal and follow the signal strength to arrive at the specific location. The ultrasonic sound guide system is useful device to localize the place in near field without touching the braille. The receiver device can be any independent form such as eyeglasses, neckband, walking cane attachment device, hand-held device, etc. those are not blocking the ear canal. Also, the receiver device can be realized by smartphone application software using the hardware and sensors in the smartphone.",
  "title": "Ultrasonic sound guide system for the visually impaired"
}