JP7095854B2 - Terminal device and its control method - Google Patents

Description

The present invention relates to a technique for emphasizing or suppressing a signal arriving from outside the device.

In the above technical field, techniques for emphasizing or suppressing a signal arriving from the outside of the device are described in Patent Documents 1 to 4.

In Patent Document 1, in a rectangular flat plate-shaped mobile terminal device, four microphones are provided only at the apex of the housing, and the sound source direction of the sound generated in the surroundings is detected based on the time difference of signal arrival to each microphone. The technology to be used is disclosed.

In Patent Document 2, in a rectangular flat plate-shaped mobile terminal device, two omnidirectional microphones are provided only on the lower side of the housing, voices arriving from different directions are acquired, and different gains are applied according to the arriving direction. And the technique of performing volume correction is disclosed.

In Patent Document 3, in a rectangular flat plate-shaped mobile terminal device, a total of three microphones are arranged only on the two opposite sides of the housing so that the distances from each other are all different, and two of them are selected. Disclosed is a technique for determining the position of a sound source and suppressing noise while obtaining high signal separation performance in a wide frequency band.

In Patent Document 4, a microphone pair composed of two microphones is selected from a microphone group composed of three or more microphones based on the holding direction of the device or the signal arrival direction, and the terminal is held. A device capable of forming a directivity suitable for a desired signal regardless of the direction is disclosed.

Japanese Unexamined Patent Publication No. 2013-183286 Japanese Unexamined Patent Publication No. 2011-205324 Japanese Unexamined Patent Publication No. 2008-092512 Japanese Unexamined Patent Publication No. 2012-524505 Japanese Patent Application No. 2014-228497 Japanese Patent Application No. 2015-033430

January 1982, IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATIONS, VOL.30, NO.1, PP.27- 34, Jan. 1982) pp. 27-34 August 1972, Proceedings of IEE, Vol. 60, No. 8, (IEEE PROCEEDINGS OF IEEE, vol.60, NO.8, PP.926-934, Aug. 1972) Pages 926-934 October 1999, IEEE TRANSACTIONS ON SIGNAL PROCESSING, Vol. 47, No. 10, (IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL.47, NO.10, PP. 2677-2684 , Oct. 1999) pp. 2677 ~ 2684 2008, "Handbook of Speech Processing", Springer, Berlin Heidelberg New York (HANDBOOK OF SPEECH PROCESSING, SPRINGER, BERLIN HEIDELBERG NEW YORK, 2008.)

However, in the above-mentioned conventional technique, it is not possible to selectively emphasize or suppress the signal arriving at the terminal from the outside by using the two sensors.

An object of the present invention is to provide a technique for solving the above-mentioned problems.

In order to achieve the above object, the apparatus according to the present invention is
As a signal input means, it is a terminal device having a rectangular flat plate shape having only two sensors, a first sensor and a second sensor, on the front surface of the outer peripheral portion.
The straight line connecting the first sensor and the second sensor is not parallel to any outer periphery of the terminal device, and is not parallel.
A signal processing means for enhancing or suppressing the signal by using the arrival time difference between the signals arriving at the first sensor and the second sensor from the outside of the terminal device is provided.
The first sensor and the second sensor are provided on each of the outer peripheral portions constituting the two sides sandwiching one corner of the terminal device, one at a position other than the corner of the terminal device, and from the corner. The distances to the first sensor and the second sensor are substantially the same ,
It is a terminal device that performs selective signal enhancement or signal attenuation according to a direction when a straight line connecting the first sensor and the second sensor is held at a non-zero angle with a horizontal plane .

In order to achieve the above object, the method according to the present invention
As a signal input means, it is a control method of a terminal device having a rectangular flat plate shape having only two sensors, a first sensor and a second sensor, on the front surface of the outer peripheral portion.
The straight line connecting the first sensor and the second sensor is not parallel to any outer periphery of the terminal device, and is not parallel.
The first sensor and the second sensor are provided on each of the two sides sandwiching one corner of the terminal device, both at positions other than the corners of the terminal device, and the first sensor is provided from the corner. And the distance to the second sensor is almost the same ,
When the straight line connecting the first sensor and the second sensor is held at a non-zero angle with the horizontal plane, selective signal enhancement or signal attenuation according to the direction is performed .
It is a control method of a terminal device that emphasizes or suppresses the signal by using the arrival time difference between the signals arriving at the first sensor and the second sensor from the outside of the terminal device.

According to the present invention, two sensors can be used to selectively enhance or suppress signals arriving at a terminal from the outside.

It is a block diagram which shows the structure of the terminal apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the functional structure of the terminal apparatus which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the appearance composition and signal processing of the terminal apparatus which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the appearance composition and signal processing of the terminal apparatus which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the appearance composition and signal processing of the terminal apparatus which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the appearance composition and signal processing of the terminal apparatus which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the appearance composition and signal processing of the terminal apparatus which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the appearance composition and signal processing of the terminal apparatus which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the appearance composition and signal processing of the terminal apparatus which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the appearance composition and signal processing of the terminal apparatus which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the appearance composition and signal processing of the terminal apparatus which concerns on 3rd Embodiment of this invention. It is a figure for demonstrating the appearance composition and signal processing of the terminal apparatus which concerns on 4th Embodiment of this invention. It is a figure for demonstrating the appearance structure and signal processing of the terminal apparatus which concerns on 5th Embodiment of this invention. It is a figure for demonstrating the appearance structure and signal processing of the terminal apparatus which concerns on 5th Embodiment of this invention. It is a figure for demonstrating the appearance structure and signal processing of the terminal apparatus which concerns on 5th Embodiment of this invention. It is a block diagram which shows the functional structure of the terminal apparatus which concerns on 6th Embodiment of this invention. It is a top view for demonstrating the signal processing of the terminal apparatus which concerns on 6th Embodiment of this invention. It is a figure for demonstrating the signal processing of the terminal apparatus which concerns on 6th Embodiment of this invention. It is a figure explaining the structure of the terminal apparatus which concerns on 7th Embodiment of this invention. It is a figure explaining the structure of the terminal apparatus which concerns on 7th Embodiment of this invention. It is a figure explaining the structure of the terminal apparatus which concerns on 8th Embodiment of this invention. It is a figure explaining the structure of the terminal apparatus which concerns on 8th Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail exemplary with reference to the drawings. However, the components described in the following embodiments are merely examples, and the technical scope of the present invention is not limited to them. Further, the "voice signal" in the following description refers to a direct electrical change caused by voice or other sound, and is for transmitting voice or other sound, and is not limited to voice.

[First Embodiment]
The terminal device 100 according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a diagram showing a configuration of a terminal device 100.

The terminal device 100 includes only two signal input means, a sensor 101 and a sensor 102. The straight line L connecting the sensor 101 and the sensor 102 is not parallel to any outer periphery of the device. Therefore, as long as any side of the outer peripheral portion of the terminal device 100 is kept horizontal, the signals arriving at the sensor 101 and the sensor 102 of the terminal device 100 have a non-zero arrival time difference regardless of the holding direction.

The terminal device 100 further includes a signal processing unit 103, and enhances or suppresses the signal by using the arrival time difference of the signals arriving at the sensor 101 and the sensor 102 from the outside of the terminal device 100.

According to the above configuration, the target signal can be extracted from the input signal without providing three or more sensors.

[Second Embodiment]
The terminal device 200 as the second embodiment of the present invention will be described with reference to FIG. 2A. The rectangular terminal device 200 is a device that emphasizes or suppresses signals from the sensor 201 and the sensor 202. These sensors 201 and 202 are not limited to acoustic sensors such as microphones, but may be ultrasonic sensors, vibration sensors, and the like. That is, the signals obtained by these sensors are voice, music, acoustic signals including natural sounds, ultrasonic signals, vibrations, and the like, but can be applied to any signal propagating as a plane wave.

As shown in FIG. 2A, the terminal device 200 includes a sensor 201, a sensor 202, a signal processing unit 240 for processing signals received from these sensors, and an output terminal 261 and an output terminal 262. The terminal device 200 further includes a display unit 220 for displaying image information. The signal processing unit 240 emphasizes or suppresses a predetermined signal with respect to the signals received from the sensor 201 and the sensor 202 to generate an output signal, and supplies the output signal to the output terminal 261 and the output terminal 262. Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 disclose a plurality of methods for performing signal enhancement or suppression.

The technique described in Non-Patent Document 1 uses the phase difference of a plurality of input signals to attenuate a target signal to generate a target block signal in which a signal other than the target signal is dominant. A deformation target block signal is generated by processing the target block signal with an adaptive filter. Further, the phase difference between a plurality of input signals is used to generate a target emphasis signal that emphasizes the target signal. The components other than the target signal remaining in the target emphasis signal are further reduced by subtracting the deformation target block signal from the target emphasis signal. Update the coefficients of the adaptive filter so that the average power of the output signal, which is the result of the subtraction, is minimized. The subtraction result obtained in this way is an output signal in which the target signal is emphasized as compared with the input signal. It is also possible to obtain an output signal in which the target signal is suppressed by processing the target emphasis signal with an adaptive filter to generate a modified target emphasis signal and subtracting it from the target block signal.

The technique described in Non-Patent Document 2 has a finite equal length after appropriately delaying each of the other signals with reference to the signal with the most delayed phase so that the phase difference (time difference) of the plurality of input signals is eliminated. It is processed by an impulse response length (FIR) filter, and finally the sum is calculated and output. The FIR filter coefficients are updated to minimize the mean square error of the output signal. At that time, a constraint is added that the transfer function for the target signal of the entire FIR filter becomes a unit impulse. The technique described in Non-Patent Document 2 is known to be equivalent to the technique described in Non-Patent Document 1.

The technique described in Non-Patent Document 3 introduces a coefficient value constraint adaptive filter for generating a target block signal and a coefficient norm constraint adaptive filter for generating a deformation target block signal for the technique described in Non-Patent Document 1. There is. It is possible to improve the excessive followability to the fluctuation of the target signal and reduce the distortion of the output signal.

The technique described in Patent Document 5 obtains the phase difference of an input signal for each frequency component, and enhances or suppresses the signal by applying a gain between 0 and 1 based on a preset phase difference-gain characteristic. I do. By using different phase difference-gain characteristics for each frequency component and setting the value of the phase difference proportional to the frequency, the signal passage angle width in the spatial direction is made constant regardless of the frequency. The technique described in Patent Document 5 can realize sharp spatial signal selectivity with a smaller number of sensors as compared with the techniques described in Non-Patent Documents 1 to 3. In addition, by appropriately designing the phase difference-gain characteristics, specifically, by setting multiple pass direction bands, signals arriving from multiple different directions can pass at the same time, and signals arriving from other directions. Can be suppressed.

In the technique described in Patent Document 6, the phase difference-gain characteristic obtained by the same method as the technique described in Patent Document 5 is applied to the signals of all the sensors in common. By applying a common gain, it is possible to maintain the correlation between multiple input signals existing at the input, and for multi-channel signals such as stereo signals, spatial selectivity is achieved without changing the sound source localization. It can be realized.

In the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6, a technique of using a plurality of sensors to emphasize or suppress signals arriving from spatially different directions is a technique of using a plurality of sensors to enhance or suppress signals. Use the phase difference. Therefore, it becomes a problem whether or not there is a phase difference corresponding to the signal arrival direction between the signals in the plurality of sensors. This problem depends on how the plurality of sensors are mounted on the terminal, in which direction the terminal is held, how the signal sources are distributed in space, and the like.

In a typical terminal usage scene, for example, assuming that the target signal source is the first speaker and the disturbing signal source is the second speaker, and the heights of both speakers are the same, each speaker's height is the same. The mouth, or signal source, resides on the same plane O at a height equal to height above the ground or floor. On the other hand, it is assumed that the terminal is held so that the main sides of the terminal are horizontal. In the present embodiment, since the terminal device 200 is rectangular as shown in FIGS. 2B and 2C, the terminal is held so that the lower side and the upper side of the terminal are horizontal.

As shown in FIGS. 2A, 2B, and 2C, the rectangular terminal device 200 includes an outer peripheral portion 210 outside the display unit 220. The terminal device 200 includes two sensors 201 and 202. The two sensors 201 and 202 are provided one by one on the outer peripheral portion 210 constituting the two adjacent sides of the terminal device 200 with the apex A interposed therebetween.

The sensor 201 and the sensor 202 are arranged other than the vertices. Therefore, the straight line connecting the sensor 201 and the sensor 202 forms a non-zero angle with any side constituting the outer circumference of the device regardless of the positions on the sides AB and DA of these sensors. If the terminal device 200 is held so that any of the side AB, the side BC, the side CD, and the side DA is horizontal, the straight line connecting the sensor 201 and the sensor 202 forms a non-zero angle with the horizontal plane. .. Since the sensor 201 and the sensor 202 are located on two adjacent sides constituting the outer circumference of the device and the two adjacent sides are at right angles to each other, the angle θ formed by the straight line connecting the sensor 201 and the sensor 202 with the side constituting the outer circumference is set. This is because it becomes non-zero.

By arranging the two sensors at an angle to the side of the terminal, the horizontal distance between the sensors becomes non-zero regardless of whether the terminal is held horizontally or vertically. Therefore, assuming that the signals arriving from different directions are plane waves, the signals in the two sensors have an arrival time difference corresponding to the signal arrival direction. When this time difference is divided by the speed of the signal received by the sensor to obtain the distance, this distance corresponds to the signal arrival direction. If the signal arrival direction is known, the gain or attenuation according to the direction can be given accordingly by the method of Patent Document 5 or 6, and selective signal enhancement or signal attenuation can be performed.

On the other hand, if two sensors are placed on the same side, the sensor spacing along the horizontal plane will be zero when placed on the upper or lower side for vertical holding, and when placed on the right or left side for horizontal holding. .. Therefore, when signals arriving from different directions along the horizontal plane are captured by the two sensors, there is no difference in arrival time between the two signals. Therefore, the signal arrival direction cannot be estimated, and selective signal enhancement or signal attenuation based on the arrival direction cannot be performed.

<When the height of the target signal source and the interference signal source are the same and they are on the same horizontal plane O as the side AB>
As shown in FIGS. 2B and 2C, the terminal device 200 is held so that the apex A included in the edge portion and the side AB passing through the apex B are horizontal, and include at least one target signal and one jamming signal. It is assumed that a plurality of signal sources exist in different directions on the same horizontal plane O. That is, the heights of the plurality of signal sources from the ground surface or the floor surface are all equal, and they exist on the same horizontal plane O. Further, it is assumed that the terminal device 200 is held at a height such that the horizontal plane O includes the side AB as shown in FIGS. 2B and 2C. FIG. 2B illustrates an example in which the side BC of the terminal device 200 is perpendicular (perpendicular to the horizontal plane O), and FIG. 2C shows an example in which the side BC of the terminal device 200 forms an angle smaller than π / 2 with the horizontal plane O. Further, assuming that the signal source S is sufficiently far from the terminal device 200 with respect to the wavelength of the signal, the signal S0 and the signal S1 arriving at the sensor 201 and the sensor 202 can be approximately regarded as a plane wave.

Assuming that the distance (shortest distance) between the sensor 201 and the sensor 202 is d and the angle formed by the straight line L connecting the sensor 201 and the sensor 202 and the side AB is θ, the sensor distance along the horizontal plane O including the side AB is It becomes dcosθ. As shown in FIG. 2B, it corresponds to the relative time difference τ between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202 from the signal source S in the direction forming an angle φ with the side AB on the horizontal plane O including the side AB. The distance τ / c obtained can be expressed as dcosθsinφ using the distance d between the sensors. Here, c is the propagation speed of the signal received by the sensor, and in the case of an acoustic signal, it is the speed of sound. That is, dcosθsinφ = τ / c.

If τ is measured, since d, θ, and c are known, the above equation can be solved for φ to obtain the arrival direction φ of the signal S. That is, on the horizontal plane O including the side AB, the relative time difference τ (equivalently also the relative phase difference) between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202 is measured with respect to the signal arriving from the direction φ. By doing so, it becomes possible to obtain φ and estimate the signal arrival direction. For example, if there is a sensor on the side AB, when the terminal is rotated π / 2 and the side AB is held so as to be vertical, the signal of the two sensors has no time difference with respect to the signal from all directions along the horizontal plane. become. Therefore, it is not possible to emphasize or attenuate the signal according to the direction by estimating the direction by the time difference of the signal, which is a problem. If the two sensors are arranged diagonally, there will be a time lag depending on the direction of arrival of signals coming from all directions on the horizontal plane, regardless of whether they are held horizontally or vertically. This time difference becomes zero for a signal arriving from the front, but is different for all directions including the front, so that the signal arrival direction can be estimated.

Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signals S input to the sensor 201 and the sensor 202 to make the signals S different on the horizontal plane O including the side AB. Signals coming from a direction can be emphasized or suppressed.

<When the height of the target signal source and the interference signal source is the same as that of the side AB, and unlike the height of the side AB, it is on a plane inclined by δ1 in front of the terminal>
Next, as shown in FIG. 2D, the heights of the plurality of signal sources S1 and S2 including at least one target signal and one jamming signal and the horizontal plane on which the side AB exists are different from the ground surface or the floor surface. Consider the case where it exists on the horizontal plane. In this case, it can be considered that the plurality of signal sources including at least one target signal and one jamming signal and the side AB exist in the plane O1 forming the angle δ1 with the horizontal plane O. Regarding the relative time difference τ between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202 on the plane O1, the same equation as on the plane O holds, and dcosθsinφ = τ / c.

That is, even on the horizontal plane O1 in which the horizontal plane O on which the side AB exists is tilted by δ1, the relative time difference τ (relative time difference τ) between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202 with respect to the signal arriving from the direction φ on O1. By measuring the relative phase difference equivalently), it is possible to obtain φ and estimate the signal arrival direction. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signals S input to the sensor 201 and the sensor 202 to make the signals S different on the horizontal plane O1 including the side AB. Signals coming from a direction can be emphasized or suppressed.

<When the height of the target signal and the interference signal are different and they are on a plane tilted δ2 to the left>
Next, consider a case where the plane O2 in which a plurality of signal sources including at least one target signal and one jamming signal are present is tilted δ2 to the right on the horizontal plane O in which the side AB is present. This corresponds to the case where the heights of the first speaker and the second speaker are different, such as signals from adults and children, humans and small robots. In this case, as shown in FIG. 2E, the side AB does not exist on the plane O2 where the target signal and the interference signal exist. However, since the relative time difference τ between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202 occurs on the plane O2, the distance dcos (θ + δ2) between the sensor 201 and the sensor 202 along the plane O2 is used. The same relationship as in the case of the horizontal plane O is established.
dcos (θ + δ2) sinφ = τ / c

Here, what is different from the case of the horizontal plane O is the existence of δ2, and usually δ2 is unknown. However, if the signal source is sufficiently far from the terminal device 200 with respect to the wavelength of the signal, and the signal S0 and the signal S1 arriving at the sensor 201 and the sensor 202 can be approximately regarded as a plane wave, δ2 is approximate. Can be regarded as zero. Therefore, in the case of the plane O2 as well as in the case of the horizontal plane O, dcos (θ + δ2) sinφ≈dcosθsinφ = τ / c can be set. That is, even on the horizontal plane O2 in which the horizontal plane O on which the side AB exists is tilted δ2 to the left, the signal S0 and the signal S1 input to the sensor 201 and the sensor 202 are relative to the signal arriving from the direction φ on the O2. By measuring the time difference τ (also equivalently the relative phase difference), it is possible to obtain φ and estimate the signal arrival direction. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signals S input to the sensor 201 and the sensor 202 to make the signals S different on the horizontal plane O2 including the side AB. Signals coming from a direction can be emphasized or suppressed.

<Combination of the previous two examples>
Next, consider a plane O3 tilted δ1 in front of the terminal and δ2 to the right with respect to the horizontal plane O. Such a plane can be considered as a combination of the plane O1 and the plane O2. The distance between the sensor 201 and the sensor 202 with respect to the signal S arriving from the direction φ on the plane O3 is dcos (θ + δ2), and dcos (θ + δ2) sinφ≈dcosθsinφ = τ / c as in the case of the horizontal plane O2. That is, by measuring the relative time difference τ (equivalently also the relative phase difference) between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202, φ can be obtained and the signal arrival direction can be estimated. .. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signals S input to the sensor 201 and the sensor 202 to make the signals S different on the horizontal plane O3 including the side AB. Signals coming from a direction can be emphasized or suppressed.

Since all planes can be thought of as planes tilted by δ2 to the left and δ1 to the front, multiple signal sources including at least one target signal and one jamming signal were distributed on any plane. Even so, it is possible to obtain φ and estimate the signal arrival direction by measuring the relative time difference τ (equivalently also the relative phase difference) between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202. Become. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signal S input to the sensor 201 and the sensor 202 to emphasize or suppress the signal arriving from the direction. can do.

<When the holding state of the terminal is not horizontal but tilted>
Next, consider a case where the terminal device 200 is held at an α inclination to the left from the horizontal plane O as shown in FIG. 2F. At this time, when the sensor 201 and the sensor 202 are projected onto the horizontal plane P, the interval is dcos (θ + α), and becomes zero when α = 0.5π−θ. Therefore, except when α = 0.5π-θ (that is, when the terminal device 200 is held so that the sensor 201 and the sensor 202 are vertically aligned), when the terminal device 200 is held at an angle. However, by measuring the relative time difference τ (equivalently also the relative phase difference) between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202, φ can be obtained and the signal arrival direction can be estimated. .. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signals S input to the sensor 201 and the sensor 202 to make the signals S different on the horizontal plane O1 including the side AB. Signals coming from a direction can be emphasized or suppressed.

When the inclination of the terminal device 200 is α = 0.5π-θ, as described above, the relative time difference τ (equivalently relative phase difference) between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202. It is impossible to obtain φ and estimate the signal arrival direction by measuring (also). However, normally, when the user holds the terminal, the upper side or the lower side of the terminal is kept horizontal, so that α = 0.5π−θ does not hold. Furthermore, even if the value of α = 0.5π-θ itself and the probability of occurrence of α are assumed to be a uniform distribution, the probability of occurrence is extremely low. Therefore, it is not a big problem that it becomes impossible to estimate the signal arrival direction only when α = 0.5π−θ.

<When the holding state of the terminal is not horizontal but vertical>
Next, consider rotating the terminal device 200 90 degrees to the right from the state of FIG. 2A so that the side AB is vertical and the side DA is horizontal (upper side) as shown in FIG. 2G. At this time, the distance between the sensor 201 and the sensor 202 along the horizontal plane Q including the side DA or the horizontal plane parallel to Q is dsinθ = dcos (0.5π−θ). For signals arriving from the horizontal plane Q and the horizontal plane parallel to it from a direction forming an angle φ with the side DA, the distance τ / c corresponding to the relative time difference τ of the signals input to the sensor 201 and the sensor 202 is It becomes dsinθsinφ. That is, the relative time difference between the signals input to the sensor 201 and the sensor 202 with respect to the signal arriving from the direction φ on the horizontal plane Q including the side DA or on the horizontal plane parallel thereto is (equivalently also the relative phase difference). It is a value corresponding to the arrival direction φ and can be estimated by dsinθsinφ = τ / c. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signals input to the sensor 201 and the sensor 202, and the horizontal plane Q including the side DA or parallel thereto is applied. Signals coming from different directions on the plane can be emphasized or suppressed.

<When the holding state of the terminal is tilted α from vertical to left>
Consider a case where the terminal device 200 held vertically (vertically) as shown in FIG. 2G is tilted by an angle α as in FIG. 2F. At this time, the distance between the sensor 201 and the sensor 202 along the horizontal plane is dsin (θ + α), and becomes zero when α = −θ. Therefore, except in the case of α = −θ, the relative time difference τ (equivalently relative position) between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202 even when the terminal device 200 is tilted and held. By measuring (also the phase difference), φ can be obtained and the signal arrival direction can be estimated. Therefore, by applying the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 to the signals S input to the sensor 201 and the sensor 202, the horizontal plane Q including the side DA is α to the left. Signals coming from different directions on a tilted plane can be emphasized or suppressed.

When the inclination of the terminal device 200 is α = −θ, as described above, the relative time difference τ (equivalently also the relative phase difference) between the signal S0 and the signal S1 input to the sensor 201 and the sensor 202 is set. It is impossible to obtain φ and estimate the signal arrival direction by measuring. However, normally, when the user holds the terminal, the upper part or the lower side of the terminal is kept horizontal, so that α = −θ does not hold. Furthermore, even if the value of α = −θ itself and the probability of occurrence of α are assumed to be a uniform distribution, the probability of occurrence is extremely low. Therefore, it is not a big problem that it becomes impossible to estimate the signal arrival direction only in the case of α = −θ.

As described above, if the sensor spacing when a straight line connecting the two sensors is projected onto the plane where the signal source exists is non-zero, the signals input to the sensor 201 and the sensor 202 are in the signal arrival direction. It has a relative time difference (and relative phase difference) τ ≠ 0 according to φ.

In the example of FIG. 2B, the sensor spacing is dcosθ, and in the example of FIG. 2G, dsinθ = dcos (0.5π−θ). As long as the sensor 201 is located on the side DA and the sensor 202 is located on the side AB, 0 <θ <0.5π. Also, d is non-zero for the two sensors. That is, among the various holding states of the terminal device 200, the sensor spacing on the plane in which the signal source is present takes a non-zero value in most cases. Therefore, by applying the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 to the signals input to the sensor 201 and the sensor 202, a specific direction on the horizontal plane in which the signal source is present is applied. The signal coming from can be emphasized or suppressed.

Similarly, when the terminal device 200 is further rotated 90 degrees to the right from the state of FIG. 2G so that the side AB becomes horizontal (lower side), and the side DA is rotated 90 degrees to the left from the state of FIG. 2B. The same argument as in FIG. 2B and FIG. 2G holds for the case where the horizontal (lower side) is set. That is, the sensor intervals when the side AB is horizontal (lower side) and when the side DA is horizontal (lower side) are dcosθ and dsinθ = dcos (0.5π-θ), respectively, and both are in most cases. Takes a non-zero value. Therefore, by applying the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 to the signals input to the sensor 201 and the sensor 202, a specific direction on the horizontal plane in which the signal source is present is applied. The signal coming from can be emphasized or suppressed.

As described above, according to the present embodiment, the terminal holding direction is parallel to a plurality of different terminal holding directions (four states in which either side AB or side DA is horizontal as an upper side or a lower side). Signals arriving from a particular direction on a horizontal plane (a plane containing either side AB or side DA) can be selectively enhanced or suppressed using two sensors.

Summarizing the above description, according to the present embodiment, it is possible to selectively emphasize or suppress signals coming from various directions with respect to a plurality of different terminal holding states by using two sensors.

Although the sensor 201 and the sensor 202 arranged at positions sandwiching the apex A of the terminal device 200 have been described above, there is no distinction between the vertices of the terminal device 200, and these sensors are any of the vertices B, C, and D. Needless to say, it may be arranged at a position sandwiching the.

With such a configuration and the arrangement of the sensors, the terminal device 200 can selectively emphasize or suppress signals arriving from various directions outside the device with the two sensors for a plurality of different terminal holding directions.

As shown in FIG. 2H, even when the outer peripheral portion 275 of the terminal device 270 has a pentagonal shape, the straight line connecting the sensors is not parallel to any side of the outer peripheral portion 275. As described above, if the two sensors 271 and 272 are provided, the same effect as described above can be obtained.

Further, as shown in FIG. 2I, even when the shape of the outer peripheral portion 285 of the terminal device 280 is hexagonal, the straight line connecting the sensors is not parallel to any side of the device in any side of the outer peripheral portion 285. As described above, if the two sensors 281 and 282 are provided, the same effect as described above can be obtained.

Further, the sensor arrangement of the present embodiment can be similarly applied to the case where the outer peripheral portion of the terminal device has a heptagon or more, and the same effect can be obtained.

[Third Embodiment]
The terminal device 300 as the third embodiment of the present invention will be described with reference to FIG. Since the terminal device 300 is the same as the first embodiment except for the installation position of the sensor, the details of its operation will be omitted, and only the difference caused by the different sensor positions will be described.

As shown in FIG. 3, the terminal device 300 includes a display unit 320 which is rectangular and smaller than the outer peripheral portion 310. The terminal device 300 is equipped with one sensor 301 and one 302 on the outer peripheral portion 310 constituting the two opposite sides AB and the side DC. The straight line L connecting the sensor 301 and the sensor 302 is not parallel to any of the sides AB, BC, CD, and DA of the device. That is, the angle θ formed by the straight line L and the side AB is not always 0.5π.

Therefore, the straight line connecting the sensors 301 and 302 forms a non-zero angle with any side constituting the outer circumference of the device regardless of the positions on the side CD and the side BA of these sensors. If the terminal device 300 is held so that any of the side AB, the side BC, the side CD, and the side DA is horizontal, the straight line L connecting the sensor 301 and the sensor 302 is non-zero with the horizontal plane or the ground plane. Make an angle of.

When the terminal device 300 is held so that the side AB including the vertices A and B is horizontal and the distance (shortest distance) between the sensor 301 and the sensor 302 is d, the sensor distance along the horizontal plane is dcosθ. However, θ is the angle formed by the straight line L connecting the sensor 301 and the sensor 302 and the side AB. Similar to FIG. 2B, for the signals S0 and S1 arriving from the direction on the horizontal plane forming an angle φ with the side AB, the relative time difference τ of the signals input to the sensor 301 and the sensor 302 is cdcosθsinφ. That is, for a signal arriving from a specific direction on a plane including the side AB and parallel to the ground plane or the horizontal plane, the relative time difference between the signals input to the sensor 301 and the sensor 302 is (equivalent). The relative phase difference is also), and the value corresponds to the arrival direction φ. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 6 and 7 are applied to the signals input to the sensor 301 and the sensor 302 on a plane parallel to the ground plane or the horizontal plane including the side AB. Signals coming from different directions can be emphasized or suppressed.

When the terminal device 300 is held at an α inclination to the left as in FIG. 2F, the horizontal distance between the sensors 301 and 302 is dcos (θ + α). Therefore, except for the case of α = 0.5π−θ, the above effect is obtained even when the terminal device 300 is tilted and held.

When the terminal device 300 is held vertically so that the side AB is vertical and the side DA is horizontal (upper side), the horizontal distance between the sensors 301 and 302 is dsinθ = dcos (0.5π−θ). For a signal arriving from a direction on the horizontal plane forming an angle φ with the side DA, the relative time difference τ of the signals input to the sensors 301 and 302 is cdsinθsinφ. Further, even when the terminal device 300 is held tilted to the left by α from that state, the horizontal distance between the sensors 301 and 302 is dsin (θ + α), and becomes zero when α = −θ. Therefore, the above effect is obtained except in the case of α = −θ.

Therefore, similarly to the second embodiment, the ground plane including the side DA is applied to the signals input to the sensors 301 and 302 by applying the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 6 and 7. Alternatively, signals coming from different directions on a plane parallel to the horizontal plane can be emphasized or suppressed.

Similarly, the same argument holds for the case where the terminal device 300 is held so that the side AB is horizontal (lower side) and the side DA is held so as to be horizontal (lower side). That is, the sensor intervals when the side AB is horizontal (lower side) and when the side DA is horizontal (lower side) are dcosθ and dsinθ = dcos (0.5π−θ), respectively, and θ = 0.5π. Except for cases, they all take non-zero values. Therefore, by applying the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 6 and 7 to the signals input to the sensors 301 and 302, the signals come from a specific direction on the horizontal plane in which the signal source exists. The signal can be emphasized or suppressed.

When the signal source exists on the plane O1 described with reference to FIG. 2D, the distance between the sensor 301 and the sensor 302 on the plane O1 is dcosθ. Therefore, except when θ = 0.5π, the signal obtained from the sensor 301 or the sensor 302 has a non-zero phase difference (time difference), and the signal arriving from the direction φ on the plane O1 is referred to in Non-Patent Document 1. 3 and the techniques described in Patent Documents 6 and 7 can be applied to emphasize or suppress.

Further, when the signal source exists on the plane O2 described with reference to FIG. 2E, the distance between the sensors 301 and 302 on the plane O2 is dcos (θ + δ2). Further, as described with reference to FIG. 2E, it can be regarded as δ2 = 0. Therefore, except when θ = 0.5π, the signal obtained from the sensor 301 or the sensor 302 has a non-zero phase difference (time difference), and the signal arriving from the direction φ on the plane O2 is referred to in Non-Patent Document 1. 3 and the techniques described in Patent Documents 6 and 7 can be applied to emphasize or suppress.

As can be seen from the examples of these two types of planes O1 and O2, signals arriving from a specific direction on a plane that is not parallel to the terminal holding direction are also described in Non-Patent Documents 1 to 3 and Patent Documents 6 and 7. It can be emphasized or suppressed by applying other techniques.

With such a configuration and the arrangement of the sensors, the terminal device 300 can selectively emphasize or suppress signals arriving from various directions outside the device with the two sensors for a plurality of different terminal holding directions.

The case where the sensor 301 is arranged on the side AB and the sensor 302 is arranged on the side CD has been described above as an example, but the same explanation is given that one sensor is arranged on each side DA and one sensor is arranged on the side BC. This is true even in the case.

[Fourth Embodiment]
The terminal device 400 as the fourth embodiment of the present invention will be described with reference to FIG. Since the terminal device 400 is the same as the second embodiment except for the installation position of the sensor, the details of its configuration and operation will be omitted, and only the difference caused by the different sensor positions will be described.

The terminal device 400 includes a display unit 420 that is smaller than the outer peripheral portion 410 of the rectangle. The terminal device 400 includes sensors 401 and 402 on a diagonal outer peripheral portion 410, that is, one sensor 401 and one on each of two non-adjacent vertices B and D, respectively. Instead of these sensors, one sensor may be provided at each of the apex A and the apex C.

When the terminal device 400 is held so that the side AB is horizontal and the upper side, and the distance (shortest distance) between the sensors 401 and 402 is d, the sensor distance along the horizontal plane is dcosθ. Therefore, the signal can be emphasized or suppressed by applying the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 6 and 7 to the signals input to the sensors 401 and 402. Similarly, in various cases shown in FIGS. 2C to 2G, such as when the terminal device 400 is held at an angle or when the signal source exists at an angle with the horizontal plane O including the side AB. The signal can be emphasized or suppressed by applying the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 6 and 7 to the signals input to the sensors 401 and 402.

According to the present embodiment, with such an arrangement of sensors, the terminal device selectively emphasizes or suppresses signals arriving from various directions outside the device with two sensors for a plurality of different terminal holding directions. be able to.

[Fifth Embodiment]
The terminal device 500 as the fifth embodiment of the present invention will be described with reference to FIG. Since the terminal device 500 is the same as the second embodiment except for the installation position of the sensor, the same reference numerals are given to the same configuration, the details thereof are omitted, and only the differences caused by the different sensor positions will be described. do.

The terminal device 500 is equipped with two sensors 501 and 502 in the outer peripheral portion 510 constituting one side AB. The sensor 501 and the sensor 502 are both in the side AB, but the straight line L connecting the sensor 501 and the sensor 502 is not parallel to any side AB, BC, CD, DA of the device.

Also in the present embodiment, as in the second embodiment, the relative time difference (equivalently the relative phase difference) of the signals input to the sensors 501 and 502 is a value corresponding to the arrival direction. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signals input to the sensors 501 and 502 to emphasize or suppress the signals arriving from the outside of the device. Can be done.

It goes without saying that the two sensors 501 and 502 are not limited to being arranged on the side AB, and the same effect can be obtained regardless of whether they are arranged on the side BC, the side CD, or the side DA.

That is, according to the present embodiment, by arranging such sensors, the terminal device 500 selectively emphasizes signals coming from various directions outside the device with respect to a plurality of different terminal holding directions by the two sensors. Or it can be suppressed.

As shown in FIG. 6, even when the shape of the outer peripheral portion 610 of the terminal device 600 is pentagonal, the straight line connecting the sensors is not parallel to any side of the device in any side of the outer peripheral portion 610. As described above, if the two sensors 601 and 602 are provided, the same effect as described above can be obtained.

Further, as shown in FIG. 7, even when the shape of the outer peripheral portion 710 of the terminal device 700 is hexagonal, the straight line connecting the sensors is not parallel to any side of the device in any side of the outer peripheral portion 710. As described above, if the two sensors 701 and 702 are provided, the same effect as described above can be obtained.

Further, the sensor arrangement of the present embodiment can be similarly applied to the case where the outer peripheral portion of the terminal device has a heptagon or more, and the same effect can be obtained.

[Sixth Embodiment]
The terminal device 800 as the sixth embodiment of the present invention will be described with reference to FIG. The terminal device 800 is different from the second embodiment in that it includes a correction unit 801 and an input terminal 820. Since other configurations and operations are the same as those of the second embodiment, the same configurations and operations are designated by the same reference numerals and detailed description thereof will be omitted.

<Operation of the correction unit>
The correction unit 801 generates a delay input signal by giving different delays to the signals received from the sensor 201 and the sensor 202 by using the delay information received from the input terminal 820. Further, the delay input signal is transmitted to the signal processing unit 240. The delay given to the signal received from the sensor 201 and the signal received from the sensor 202 shifts the directivity generated in the signal processing unit 240 to the right or left by the angle corresponding to the given delay. .. Such a directional shift is called beam steering. By processing the beam-steered signal in the correction unit 801 by the signal processing unit 240, more accurate signal enhancement or attenuation can be performed. The reason will be described with reference to FIG.

<Reason why correction unit 801 is required>
FIG. 9 is a top view of the terminal device 800 provided with the sensor 201 and the sensor 202 on the side AB as in FIG. 2B. Normally, the terminal device 800 is used under the assumption that the target signal arrives from the direction perpendicular to the display surface. When the user holds the terminal device 800 so as to satisfy this condition, the target signal is present in front of the midpoint U0 with respect to the side AB of the terminal device 800. That is, the straight line U0U1 connecting the position U1 of the target sound source and the midpoint U0 intersects the side AB at a right angle. However, since the midpoint U2 of the line segment obtained by projecting the straight line L connecting the sensor 201 and the sensor 202 onto the side AB and the midpoint U0 of the side AB do not match, the straight line U1U2 connecting the midpoint U2 and the position U1 of the target sound source is , Not perpendicular to side AB.

Assuming that the angle formed by the side AB with the straight line U1U2 is Δ and the direction corresponding to the front of the terminal device 800 (the surface with the display unit) at right angles to the side AB is 0, the signal of the target signal source in front of the terminal device 800 arrives. The direction is −Δ. In order to correct this, the correction unit 801 steers the signals received from the sensor 201 and the sensor 202 by + Δ. The signal arriving from the −Δ direction arrives at the sensor 201 first, and arrives at the sensor 202 later than that. The correction unit 801 outputs the signal arriving at the sensor 202 with a delay while keeping the signal arriving at the sensor 202, so that the delayed input signal transmitted to the signal processing unit 240 arrives at the sensor 201 and the sensor 202 at the same time. Make it equal to the signal. The delay time or equivalent phase difference required for this is provided to the input terminal 820.

Further, instead of the delay time, information regarding the size of the terminal device 800 and the arrangement of the sensor 201 and the sensor 202 can be supplied to the input terminal 820, and the delay time can be obtained by the correction unit 801.

<Calculation of delay time in correction unit 801>
Assuming that the length of the line segment U0U2 is d ₀₂ and the length of the line segment U0U1 is d ₀₁ , the distance d ₀₃ corresponding to the delay time added by the correction unit 801 is d ₀₃ = d ₀₂ from the extracted diagram of FIG. It is sinΔ, and the delay time is given by τ ₀₃ = (d _{02 sinΔ} ) / c.

<Estimation of angle Δ>
The length d ₀₂ of the line segment U0U2 can be obtained if the details of the terminal device 200 are specified. Further, the Δ corresponding to the signal arrival direction (Direction of Arrival: DOA) can be estimated by using the signals arriving at the sensor 201 and the sensor 202. Various methods for estimating the signal arrival direction are known, and methods using the phase difference of signals arriving at multiple sensors (for example, cross-correlation method, mutual spectral power analysis method, GCC-PHAT, etc.) and MUSIC method are used. A representative subspace method and the like are disclosed in Non-Patent Document 4. The angle Δ may be estimated by another device and supplied to the input terminal 820 together with the length d ₀₂ of the line segment U0U2.

で与えられ、最終的に遅延時間はτ₀₃は、

となる。このうち、線分Ｕ０Ｕ２の長さｄ₀₂は、端末装置２００の詳細が特定されれば求めることができる。線分Ｕ０Ｕ１の長さｄ₀₁が未知であるが、目標信号源のおよその位置がわかれば、近似値を得て用いることができる。例えば、端末装置２００を両手で保持して利用するときに、利用者の声を目標信号としてとらえるならば、ｄ₀₁＝０．５ｍとすることができる。すなわち、入力端子８２０には、線分Ｕ０Ｕ１の長さｄ₀₁と線分Ｕ０Ｕ２の長さｄ₀₂を供給する。 <Approximate calculation of angle Δ>
The angle Δ formed by the side AB with the straight line U1U2 can also be obtained by approximate calculation as follows. Since sin Δ is sin ² Δ + con ² Δ = 1,

Given in, the final delay time is τ ₀₃ ,

Will be. Of these, the length d ₀₂ of the line segment U0U2 can be obtained if the details of the terminal device 200 are specified. The length d ₀₁ of the line segment U0U1 is unknown, but if the approximate position of the target signal source is known, an approximate value can be obtained and used. For example, if the user's voice is captured as a target signal when the terminal device 200 is held and used with both hands, d ₀₁ = 0.5 m can be set. That is, the input terminal 820 is supplied with the length d ₀₁ of the line segment U0U1 and the length d ₀₂ of the line segment U0U2.

Beam steering is realized by adding τ ₀₃ obtained in this way or an approximate value thereof to the signal arriving earlier at the sensor 201 to obtain a delayed input signal. Which signal of the sensor 201 or the sensor 202 is delayed depends on which signal is in phase. That is, since a negative delay cannot be added, the signal to be delayed is always the signal of the sensor 201 and the sensor 202, whichever has the advanced phase.

<Simultaneous correction of amplitude and delay in the correction unit 801>
Although the method of realizing the beam steering by delaying the signal of either the sensor 201 or the sensor 202 has been described so far, the correction unit 801 may correct the amplitude at the same time as adding the delay. Of the signals of the sensor 201 and the sensor 202, the signal having the later arrival time is greatly attenuated. This is because the distance between the signal source and the sensor is long. In order to correct this, attenuation is also added to the signal to which the delay is added. This attenuation is determined and known in advance by the delay time τ ₀₃ or the corresponding distance d ₀₃ , the medium surrounding the terminal device 200, the frequency band of the signals arriving at the sensor 201 and the sensor 202, and the like. By adding attenuation at the same time as adding delay and correcting both phase and amplitude, more accurate beam steering can be performed, and the enhancement or suppression performance of the target signal can be improved.

[7th Embodiment]
The terminal device 1100 as the seventh embodiment of the present invention will be described with reference to FIG. Since the terminal device 1100 is the same as the second embodiment except for the installation position of the sensor, the details of its operation will be omitted, and only the difference caused by the different sensor positions will be described. The terminal device 1100 has a different sensor installation position as compared with the fifth embodiment (FIG. 6). Since other configurations and operations are the same as those in the fifth embodiment, the same configurations and operations are designated by the same reference numerals and detailed description thereof will be omitted.

The regular pentagonal terminal device 1100 includes a display unit 1120 that is smaller than the outer peripheral portion 1110. The outer peripheral portion 1110 is equipped with sensors 1101 and 1102 at any two adjacent vertices.

When the side CD of the terminal device 1100 is held so as to be horizontal and the lower side, and the distance (shortest distance) between the sensor 1101 and the sensor 1102 is d, the horizontal distance between the sensors is dcos (0.2π). However, 0.2π is an angle formed by the straight line L connecting the side CD and the sensors 1101 and 1102. For signals arriving from a direction forming an angle φ with the side CD on the horizontal plane including the side CD, the relative time difference τ of the signals input to the sensor 1101 and the sensor 1102 is cdcos (0.2π) sinφ. That is, for a signal arriving from any position on the plane including the side CD, the relative time difference (equivalently also the relative phase difference) of the signals input to the sensor 1101 and the sensor 1102 is in the arrival direction φ. It becomes the corresponding value. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signals input to the sensor 1101 and the sensor 1102 to be parallel to the ground plane or the horizontal plane including the side CD. Signals coming from different directions on the plane can be emphasized or suppressed.

When the terminal device 1100 is held at an α inclination to the left from the horizontal plane, the distance between the sensor 1101 and the sensor 1102 along the horizontal plane is dcos (0.2π + α). Therefore, except in the case of α = 0.3π, the above effect is obtained even when the terminal device 1100 is tilted and held. Next, as shown in FIG. 12, it is considered that the terminal device 1100 is rotated 0.4π to the right from the state of FIG. 11 so that the side BC is horizontal (lower side). At this time, the horizontal distance between the sensor 1101 and the sensor 1102 is dsin (0.1π) = dcos (0.4π). For a signal arriving from a direction on the horizontal plane forming an angle φ with the side BC, the relative time difference τ of the signals input to the sensor 1101 and the sensor 1102 is cdsin (0.1π) sinφ. Therefore, similarly to the second embodiment, the side CD is applied to the signals input to the sensor 1101 and the sensor 1102 by applying the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6. Signals coming from different directions on a plane parallel to the including ground plane or horizontal plane can be emphasized or suppressed.

Next, consider a case where the terminal device 1100 is held at an α tilt to the left from the state of FIG. 12, as in the case of FIG. 2F. At this time, the distance between the sensor 1101 and the sensor 1102 along the horizontal plane is dsin (0.1π + α), and becomes zero when α = −0.1π. Therefore, except in the case of α = −0.1π, the incoming signal can be emphasized or suppressed even when the terminal device 1100 is held at an α inclination to the left.

Similarly, when the terminal device 1100 is rotated 0.4π further to the right from the state shown in FIG. 12 so that the side AB becomes horizontal (lower side), it rotates 0.8π and the side EA becomes horizontal (lower side). In this case, the side DC is rotated 0.4π to the left from the state shown in FIG. 12 so that the side DC becomes horizontal (lower side), and the side ED is rotated 0.8π so that the side ED becomes horizontal (lower side). In this case, the same argument as in FIGS. 11 and 12 holds. That is, when the side AB is horizontal (lower side), the side EA is horizontal (lower side), the side DC is horizontal (lower side), and the side ED is horizontal (lower side), the sensor intervals are respectively. , D, dsin0.1π, dcos0.2π, and dcos0.2π, all of which take non-zero values. Therefore, by applying the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 to the signals input to the sensor 1101 and the sensor 1102, a specific direction on the horizontal plane in which the signal source is present is applied. The signal coming from can be emphasized or suppressed.

As described above, according to the present embodiment, for a plurality of different terminal holding directions (five states in which any one of the side CD, the side BC, the side AB, the side EA, and the side DE becomes horizontal as the lower side). , Signals arriving from a specific direction on a plane parallel to this terminal holding direction (a plane including any of side CD, side BC, side AB, side EA, and side DE) selectively using two sensors. Can be emphasized or suppressed.

Next, as in FIG. 2D of the second embodiment, consider a plane O1 in which the plane O is rotated downward by an angle δ1 with the side CD as an axis. The distance between the sensor 1101 and the sensor 1102 on the plane O1 is dcos (0.2π). Therefore, the signal obtained from the sensor 1101 or the sensor 1102 has a non-zero phase difference (time difference), and the signal arriving from the direction φ on the plane O1 is referred to in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6. It can be emphasized or suppressed by applying the techniques described and the like.

Next, as in FIG. 2E of the second embodiment, when the horizontal plane O including the side CD and the plane O2 form an angle δ2, that is, when the horizontal plane O2 is tilted δ2 to the left with respect to the horizontal plane O, the sensor 1101 and The distance on the plane O2 of the sensor 1102 is dcos (0.2π + δ2). Therefore, except in the case of δ = 0.3π, the signal obtained from the sensor 1101 or the sensor 1102 has a non-zero phase difference (time difference), and the signal arriving from the direction φ on the plane O2 is referred to in Non-Patent Document 1. 3 and the techniques described in Patent Document 5 and Patent Document 6 can be applied to emphasize or suppress.

As can be seen from the examples of these two types of planes O1 and O2, signals arriving from a specific direction on a plane that is not parallel to the terminal holding direction are also described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6. It can be emphasized or suppressed by applying the techniques described and the like.

Summarizing the above description, according to the present embodiment, it is specified for a plurality of different terminal holding directions (a state in which any of the side CD, the side BC, the side AB, the side EA, and the side DE is horizontal). A signal arriving from a specific direction on the plane (a plane parallel to the terminal holding direction and a plane non-parallel to the terminal holding direction) can be selectively emphasized or suppressed by using two sensors.

Although the case where the sensor 1101 is arranged at the apex A and the sensor 1102 at the apex B has been described above as an example, the same effect can be obtained when one sensor is arranged only at the apex B and the apex C. .. The same effect is obtained when one sensor is arranged only at the apex C and the apex D. The same effect is obtained when one sensor is arranged only at the apex D and the apex E, respectively. The same effect is obtained when one sensor is arranged only at the apex E and the apex A.

With such a configuration and arrangement of sensors, the terminal device 1100 selectively emphasizes or suppresses signals arriving from a specific direction on a specific plane with two sensors for a plurality of different terminal holding directions. Can be done.

[Eighth Embodiment]
The terminal device 1300 as the eighth embodiment of the present invention will be described with reference to FIGS. 13 and 14. The terminal device 1300 has a different sensor installation position as compared with the fifth embodiment (FIG. 7). Since other configurations and operations are the same as those in the fifth embodiment, the same configurations and operations are designated by the same reference numerals and detailed description thereof will be omitted.

As shown in FIGS. 13 and 14, the terminal device 1300 includes a regular hexagonal outer peripheral portion 1310 and a smaller display portion 1320. The terminal device 1300 is equipped with sensors 1301 and 1302 at any two adjacent vertices of the outer peripheral portion 1310.

When the terminal device 1300 is held so that the side AB is horizontal and the upper side, and the distance (shortest distance) between the sensor 1301 and the sensor 1302 is d, the horizontal distance between the sensors is also d. For a signal arriving from a direction on the horizontal plane forming an angle φ with the side AB, the relative time difference τ of the signals input to the sensor 1301 and the sensor 1302 is cdsinφ. That is, for a signal arriving from a specific direction on the horizontal plane including the side AB, the relative time difference (equivalently also the relative phase difference) of the signals input to the sensor 1301 and the sensor 1302 corresponds to the arriving direction φ. It becomes a value. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signals input to the sensor 1301 and the sensor 1302 from different directions on the horizontal plane including the side AB. The incoming signal can be emphasized or suppressed.

When the terminal device 1300 is held at an α tilt to the left from the horizontal plane, the distance between the sensor 1301 and the sensor 1302 along the horizontal plane is dcosα. Therefore, except in the case of α = 0.5π, the above effect is obtained even when the terminal device 1300 is tilted and held.

Next, as shown in FIG. 14, it is considered that the terminal device 1300 is rotated π / 3 to the right from the state of FIG. 13 so that the side FA is horizontal and the upper side. At this time, the distance between the sensor 1301 and the sensor 1302 along the horizontal plane is dsin (π / 6) = dcos (π / 3). For a signal arriving from a direction on the horizontal plane forming an angle φ with the side FA, the relative time difference τ of the signals input to the sensor 1301 and the sensor 1302 is cdsin (π / 6) sinφ. Therefore, the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 are applied to the signals input to the sensor 1301 and the sensor 1302 from different directions on the plane including the side FA. The incoming signal can be emphasized or suppressed.

When the terminal device 1300 is held at an α inclination to the left from the horizontal plane, the horizontal distance between the sensor 1301 and the sensor 1302 is dsin (π / 6 + α), which is zero when α = −π / 6. Therefore, except in the case of α = −π / 6, the incoming signal can be selectively emphasized or suppressed by the two sensors even when the terminal device 1300 is held at an α inclination to the left.

Similarly, when the terminal device 1300 is further rotated π / 3 to the right from the state shown in FIG. 14 so that the side EF is horizontal and the upper side, the terminal device 1300 is rotated 2π / 3 so that the side DE becomes the horizontal and the upper side. In this case, the side EF is rotated π / 3 to the left from the state shown in FIG. 13 so that the side EF is horizontal and the lower side, and the side FA is rotated 2π / 3 so that the side FA is horizontal and the lower side. , The above-mentioned effect can be achieved. That is, the sensor intervals are dcos (π) when the side EF is horizontal and the upper side, the side DE is the horizontal and the upper side, the side EF is the horizontal and the lower side, and the side FA is the horizontal and the lower side. / 3), d, dsin (π / 6), and dcos (π / 3), all of which take non-zero values. Therefore, by applying the techniques described in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6 to the signals input to the sensor 1301 and the sensor 1302, a specific direction on the horizontal plane in which the signal source is present is applied. The signal coming from can be emphasized or suppressed.

Next, as in FIG. 2D, consider a plane O1 in which the plane O is rotated downward by an angle δ1 with the side AB as an axis. The distance between the sensor 1301 and the sensor 1302 on the plane O1 is dcosδ1. Therefore, except in the case of δ = 0.5π, the signal obtained from the sensor 1301 or the sensor 1302 has a non-zero phase difference (time difference), and the signal arriving from the direction φ on the plane O1 is referred to in Non-Patent Document 1. 3 and the techniques described in Patent Documents 5 and 6 can be applied to emphasize or suppress. Next, as in FIG. 2E of the second embodiment, when the side AB is included and the horizontal plane O and the plane O2 form an angle δ2, that is, when the plane O2 is tilted δ2 to the left with respect to the horizontal plane O, the sensor 1301 And the distance on the plane O2 of the sensor 1302 is dcosδ2. Therefore, except in the case of δ2 = 0.5π, the signal obtained from the sensor 1301 or the sensor 1302 has a non-zero phase difference (time difference), and the signal arriving from the direction φ on the plane O2 is referred to in Non-Patent Document 1. 3 and the techniques described in Patent Documents 5 and 6 can be applied to emphasize or suppress.

As can be seen from the examples of these two types of planes, O1 and O2, signals arriving from a specific direction on a plane that is not parallel to the terminal holding direction are also included in Non-Patent Documents 1 to 3 and Patent Documents 5 and 6. It can be emphasized or suppressed by applying the techniques described in.

Summarizing the above description, according to the present embodiment, it is specified for a plurality of different terminal holding directions (a state in which any of the side AB, the side BC, the side CD, the side DE, and the side EF becomes horizontal). A signal arriving from a specific direction on the plane (a plane parallel to the terminal holding direction and a plane non-parallel to the terminal holding direction) can be selectively emphasized or suppressed by using two sensors.

With such a configuration and arrangement of sensors, the terminal device 1300 selectively emphasizes or suppresses signals arriving from a specific direction on a specific plane with two sensors for a plurality of different terminal holding directions. Can be done.

[Other embodiments]
Although the invention of the present application has been described above with reference to the embodiments, the invention of the present application is not limited to the above-described embodiment. Various changes that can be understood by those skilled in the art can be made within the scope of the invention of the present application in terms of the configuration and details of the invention of the present application. Also included in the scope of the present invention are systems or devices in which the different features contained in each embodiment are combined in any way.

Further, the present invention may be applied to a system composed of a plurality of devices, or may be applied to a single device. Furthermore, the present invention is also applicable when the signal processing program that realizes the functions of the embodiment is supplied directly or remotely to the system or device. Therefore, in order to realize the functions of the present invention on a computer, a program installed on the computer, a medium containing the program, and a WWW (World Wide Web) server for downloading the program are also included in the scope of the present invention. ..

[Other expressions of the embodiment]
Some or all of the above embodiments may also be described, but not limited to:
(Appendix 1)
As a signal input means, it is a terminal device provided with only two sensors, a first sensor and a second sensor, on the outer peripheral portion.
The straight line connecting the first sensor and the second sensor is not parallel to any outer periphery of the terminal device, and is not parallel.
A terminal device provided with a signal processing means for emphasizing or suppressing the signal by using the arrival time difference between the signals arriving at the first sensor and the second sensor from the outside of the terminal device.
(Supplementary Note 2) The terminal device according to Supplementary Note 1, wherein the first and second sensors are arranged one by one on an outer peripheral portion constituting two sides sandwiching one corner of the terminal device.
(Appendix 3)
The terminal device according to Appendix 1, wherein the first and second sensors are arranged one by one on the outer peripheral portion constituting the two opposite sides of the terminal device.
(Appendix 4)
The terminal device according to Appendix 1, wherein the first and second sensors are arranged one by one on the outer peripheral portion constituting the diagonal of the terminal device.
(Appendix 5)
The terminal device according to Appendix 1, wherein both the first and second sensors are arranged in an outer peripheral portion constituting one side of the terminal device.
(Appendix 6)
The terminal device according to any one of Supplementary note 1 to 5, wherein the outer periphery of the terminal device has four or more corners.
(Appendix 7)
The terminal device according to any one of Supplementary note 1 to 6, which is a quadrangular flat plate shape provided with a display screen.
(Appendix 8)
The terminal device according to any one of Supplementary note 1 to 7, further comprising a correction unit that gives different delays to signals received from the first and second sensors using delay information.
(Appendix 9)
It is a control method of a terminal device provided with only two sensors, a first sensor and a second sensor, as signal input means.
The straight line connecting the first sensor and the second sensor is not parallel to any outer periphery of the terminal device, and is not parallel.
A method for controlling a terminal device that emphasizes or suppresses the signal by using the arrival time difference between the signals arriving at the first sensor and the second sensor from the outside of the terminal device.
(Appendix 10)
As a signal input means, it is a control program of a terminal device provided with only two sensors, a first sensor and a second sensor, on the outer peripheral portion.
The straight line connecting the first sensor and the second sensor is not parallel to any outer periphery of the terminal device, and is not parallel.
A control program for causing a terminal device to perform a step of emphasizing or suppressing the signal by using the arrival time difference between the signals arriving at the first sensor and the second sensor from the outside of the terminal device.
(Appendix 11)
It is a terminal device whose outer periphery is formed into a polygon of pentagon or more.
As a signal input means, only two sensors, a first sensor and a second sensor, are provided at adjacent corners of the outer peripheral portion.
A terminal device provided with a signal processing means for emphasizing or suppressing the signal by using the arrival time difference between the signals arriving at the first sensor and the second sensor from the outside of the terminal device.
(Appendix 12)
It is a control method of a terminal device whose outer periphery is formed into a polygon of pentagon or more.
As a signal input means, only two sensors, a first sensor and a second sensor, are provided at adjacent corners of the outer peripheral portion.
A method for controlling a terminal device, comprising a signal processing step of emphasizing or suppressing the signal by using the arrival time difference between the signals arriving at the first sensor and the second sensor from the outside of the terminal device.
(Appendix 13)
It is a control program of a terminal device whose outer periphery is formed into a polygon of pentagon or more.
As a signal input means, only two sensors, a first sensor and a second sensor, are provided at adjacent corners of the outer peripheral portion.
A control program for a terminal device including a signal processing step for emphasizing or suppressing the signal by using the arrival time difference between the signals arriving at the first sensor and the second sensor from the outside of the terminal device.

Claims (3)

As a signal input means, it is a terminal device having a rectangular flat plate shape having only two sensors, a first sensor and a second sensor, on the front surface of the outer peripheral portion.
The straight line connecting the first sensor and the second sensor is not parallel to any outer periphery of the terminal device, and is not parallel.
A signal processing means for enhancing or suppressing the signal by using the arrival time difference between the signals arriving at the first sensor and the second sensor from the outside of the terminal device is provided.
The first sensor and the second sensor are provided on each of the outer peripheral portions constituting the two sides sandwiching one corner of the terminal device, one at a position other than the corner of the terminal device, and from the corner. The distances to the first sensor and the second sensor are substantially the same ,
A terminal device that performs selective signal enhancement or signal attenuation according to a direction when a straight line connecting the first sensor and the second sensor is held at a non-zero angle with a horizontal plane . The terminal device according to claim 1, further comprising a correction means for giving different delays to the signals received from the first and second sensors by using the delay information. As a signal input means, it is a control method of a terminal device having a rectangular flat plate shape having only two sensors, a first sensor and a second sensor, on the front surface of the outer peripheral portion.
The straight line connecting the first sensor and the second sensor is not parallel to any outer periphery of the terminal device, and is not parallel.
The first sensor and the second sensor are provided on each of the two sides sandwiching one corner of the terminal device, both at positions other than the corners of the terminal device, and the first sensor is provided from the corner. And the distance to the second sensor is almost the same ,
When the straight line connecting the first sensor and the second sensor is held at a non-zero angle with the horizontal plane, selective signal enhancement or signal attenuation according to the direction is performed .
A method for controlling a terminal device that emphasizes or suppresses the signal by using the arrival time difference between the signals arriving at the first sensor and the second sensor from the outside of the terminal device.

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