Mobile terminal, wearable terminal, sonic distance measurement system, and sonic distance measurement method

• US 10,197,673 B2
• Filed: 03/03/2016
• Issued: 02/05/2019
• Est. Priority Date: 04/03/2015
• Status: Active Grant

• Current Assignee: Sony Interactive Entertainment Inc. (Sony Group Corp.)
• Original Assignee: Sony Interactive Entertainment Inc. (Sony Group Corp.)
• Inventors: Horie, Kazuyoshi, Sasaki, Hideyuki
• Primary Examiner(s): Baghdasaryan, Hovhannes
• Application Number:
  US15/059,780
• Publication Number:
  US 20160291116A1
• Time in Patent Office: 1,069 Days
• CPC Class Codes: G01S 15/74 Systems using reradiation of acoustic waves, e.g. IFF, i.e. identification of friend or foe

Abstract

Disclosed herein is a mobile terminal including: a reproducing section adapted to reproduce a first distance measurement signal; a recording section adapted to record the first distance measurement signal and a second distance measurement signal output from other mobile terminal; a time difference measurement section adapted to measure a first difference between recording start times of the first and second distance measurement signals; a communication section adapted to receive a second difference between recording start times of the first and second distance measurement signals from the other mobile terminal, the second difference being measured by the other mobile terminal; and a distance calculation section adapted to calculate a distance to the other mobile terminal by multiplying the subtraction result between the first and second differences by the speed of sound.

Claims

1. A mobile terminal comprising:

a reproducing section adapted to reproduce a first distance measurement signal;

a recording section adapted to record the first distance measurement signal and a second distance measurement signal output from other mobile terminal;

a time difference measurement section adapted to measure a first difference between recording start times of the first and second distance measurement signals;

a communication section adapted to receive a second difference between recording start times of the first and second distance measurement signals from the other mobile terminal, the second difference being measured by the other mobile terminal;

a distance calculation section adapted to calculate a distance to the other mobile terminal by multiplying the subtraction result between the first and second differences by the speed of sound; and

a display section adapted to display information indicating that distance measurement is difficult to conduct until an environmental noise level falls down to a given threshold or less, wherein the distance measurement is not performed until the environmental noise level falls down to the given threshold or less, wherein a first posture of the mobile terminal is compared to a second posture of the other mobile terminal, and wherein distance measurement is only conducted if the first posture and the second posture match a predefined relationship.

2. The mobile terminal of claim 1 further comprising:

an edge detection section adapted to detect the recording start times of the first and second distance measurement signals by detecting edges of an envelope of sound waves of the first and second distance measurement signals.

3. The mobile terminal of claim 1 still further comprising:

a frequency conversion section adapted to acquire an environmental sound spectrum component by converting an environmental sound into a frequency range; and

a frequency selection section adapted to select, as a frequency band of the distance measurement signal sound, a frequency range in which an environmental sound spectrum component does not exceed the maximum measurable noise level, wherein the reproducing section reproduces the first distance measurement signal in the frequency band selected by the frequency selection section.

4. The mobile terminal of claim 1, wherein the other mobile terminal is a wearable terminal, and the communication section communicates with the wearable terminal by a short-range wireless communication technology.

5. A sonic distance measurement system comprising:

first and second mobile terminals;

wherein the first mobile terminal includes a reproducing section adapted to reproduce a first distance measurement signal, a recording section adapted to record the first distance measurement signal and a second distance measurement signal output from the second mobile terminal, a time difference measurement section adapted to measure a first difference between recording start times of the first and second distance measurement signals, a communication section adapted to receive a second difference between recording start times of the first and second distance measurement signals from the second mobile terminal, the second difference being measured by the second mobile terminal, and a distance calculation section adapted to calculate a distance to the second mobile terminal by multiplying the subtraction result between the first and second differences by the speed of sound; and

the second mobile terminal includes a reproducing section adapted to reproduce the second distance measurement signal, a recording section adapted to record the second distance measurement signal and the first distance measurement signal output from the first mobile terminal, a time difference measurement section adapted to measure the second difference between the recording start times of the first and second distance measurement signals, and a communication section adapted to transmit the second difference, measured by the time difference measurement section, to the first mobile terminal, wherein the distance is not calculated until an environmental noise level falls down to a given threshold or less, wherein a first posture of the first mobile terminal is compared to a second posture of the second mobile terminal, and wherein the distance is not calculated if the first posture and the second posture match a predefined relationship.

6. A sonic distance measurement method comprising:

reproducing a first distance measurement signal at a mobile terminal;

recording the first distance measurement signal and a second distance measurement signal output from a wearable terminal;

measuring a first difference between recording start times of the first and second distance measurement signals;

receiving a second difference between the recording start times of the first and second distance measurement signals from the wearable terminal, the second difference being measured by the wearable terminal; and

calculating a distance to the wearable terminal by multiplying the subtraction result between the first and second differences by the speed of sound, wherein the distance to the wearable terminal is not calculated until an environmental noise level falls down to a given threshold or less, wherein a first posture of the wearable terminal is compared to a second posture of the mobile terminal, and wherein the distance to the wearable terminal is not calculated if the first posture and the second posture do not match a predefined relationship.

7. A non-transitory computer readable medium having stored thereon a program for a computer, the program comprising:

by a reproducing section of a mobile terminal, reproducing a first distance measurement signal;

by a recording section, recording the first distance measurement signal and a second distance measurement signal output from a wearable terminal;

by a time difference measurement section, measuring a first difference between recording start times of the first and second distance measurement signals;

by a communication section, receiving a second difference between the recording start times of the first and second distance measurement signals from the wearable terminal, the second difference being measured by the wearable terminal; and

by a distance calculation section, calculating a distance to the wearable terminal by multiplying the subtraction result between the first and second differences by the speed of sound, wherein the distance to the wearable terminal is not calculated until an environmental noise level falls down to a given threshold or less, wherein a first posture of the wearable terminal is compared to a second posture of the mobile terminal, and wherein the distance to the wearable terminal is not calculated if the first posture and the second posture do not match a predefined relationship.