公开(公告)号：US09686397B1

公开(公告)日：2017-06-20

申请号：US15280325

申请日：2016-09-29

Applicant: Samsung Electronics Co., Ltd.

Inventor： Pengfei Hu ,  Yilin Shen ,  Hongxia Jin

IPC: H04B11/00 ,  H04B1/38 ,  H04M1/725 ,  H04L12/26 ,  H04W72/04

CPC classification number: H04B11/00 ,  Y02D70/142 ,  Y02D70/144 ,  Y02D70/26 ,  Y02D70/48

Abstract: A modulation method referred to as Time Shift Keying (TSK) is used to transmit messages between two devices in a highly energy efficient manner. A message represented by an inaudible audio signal is modulated on a transmitting device. The audio signal is comprised of an array of non-zero amplitude delimiter signals with time periods of zero-amplitude transmission between delimiters. The time duration of the zero-amplitude transmission periods is mapped to a symbol, multiple symbols are then assembled into a message. On the transmitting device, the audio signal is broken into pieces or sequences of bits which are mapped to symbols. On the receiving device, the time durations of zero-amplitude transmission are translated to the symbols which are assembled to the message. The delimiter signals have gradually increasing and decreasing amplitudes and have a length such that make them detectable by the receiving device.

公开(公告)号：US10581870B2

公开(公告)日：2020-03-03

申请号：US15264116

申请日：2016-09-13

Applicant: Samsung Electronics Co., Ltd.

Inventor： Yilin Shen ,  Pengfei Hu ,  Hongxia Jin

IPC: H04W48/04 ,  H04L29/06 ,  G06F1/3206 ,  G06F1/3234 ,  G06F1/3212 ,  H04W4/80 ,  H04L12/26 ,  H04W12/02 ,  G06F1/3215 ,  G06F1/3296 ,  H04W4/021 ,  H04W12/04 ,  H04W12/06 ,  H04W12/08 ,  H04W12/00

Abstract: An accurate distance between two devices can be determined in continuous and secure manner using modulated audible signals containing time-based information. This calculated distance can be used to lock and unlock one of the two devices such that if one of the devices, such as a smart phone or smart watch, is beyond a pre-configured distance from the other device, such as a laptop or tablet, the other device locks and may display a message to the user. The modulated messages contain time difference data of audible signal emission and receiving times which are used by each device to calculate an accurate estimate of the distance between the two devices.