JP2014192878A - Receiving speech quality measuring method, receiving speech quality measuring device and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To evaluate pinna vibration handset objectively by using a head and torso simulator (HATS).SOLUTION: A receiving speech quality measuring device for evaluating the acoustic transfer characteristics of a pinna vibration handset includes an input section 1 for inputting a sound wave originated from a receiver for every frequency, and recorded via a head and torso simulator, a processing section 3 for acquiring the differential characteristics of the recorded sound wave and the originated sound wave, and correcting the recorded sound wave by the differential characteristics, and a determining section 5 for determining whether or not the sound wave thus corrected satisfies a predetermined reference value.

Description

  The present invention relates to a reception quality measuring method, apparatus, and program for measuring acoustic transfer characteristics of a pinna vibration type receiver.

  Conventionally, based on "Recommendation ITU-T P.58", the call characteristics of a mobile device manufactured by a manufacturer has been evaluated. In this call characteristic evaluation, for example, loudness, transmission / reception frequency characteristic, spectrum distortion, and the like are measured, and it is evaluated whether or not the call characteristic of the mobile device satisfies the requirement of a specified value (or mask curve). “Recommendation ITU-T P.58” defines a head and torso simulator (hereinafter referred to as “HATS”) for measuring call quality in order to objectively evaluate a telephone network and a handset. (Non-Patent Document 1).

  HATS based on “Recommendation ITU-T P.58” includes, for example, “Bruel & Kjar Type 4128-D” as disclosed in Non-Patent Document 2. HATS is composed of “Pinna Simulator” that simulates the shape and rigidity of the pinna and “Ear Simulator” that simulates the characteristics of the external auditory canal in order to simulate the sound pressure received by the eardrum from the sound waves received by the pinna. Yes.

  On the other hand, in recent years, a type of handset that perceives sound by vibrating the human pinna and its surroundings to generate sound waves and transmitting the vibration to the inner ear via the ear canal and its surroundings, that is, “pinna vibration” Type receiver "has been proposed. This “auricular vibration type handset”, for example, vibrates a touch panel display with a laminated piezoelectric ceramic actuator and vibrates the human auricle to generate sound waves and transmit the vibration to the inner ear via the external auditory canal. Yes.

“Head and torso simulator for telephonometry”, Recommendation ITU-T P.58 (2011). “Head and Torso Simulator (HATS) -Type 4128-D”, URL http://bksv.com.

  However, “Pinna Simulator” is not supposed to vibrate itself. The “Ear Simulator” is configured to simulate the characteristics of the ear canal, but does not have the ear canal itself. That is, HATS cannot objectively evaluate a handset that vibrates the human pinna and its surroundings, that is, a pinna vibration type handset. Therefore, for a mobile device equipped with an auricle vibration type receiver, subjective evaluation must be performed instead of HATS objective evaluation, which increases the time and cost.

  The present invention has been made in view of such circumstances, and provides a reception quality measurement method, reception quality measurement apparatus, and program capable of objectively evaluating a pinna vibration type receiver using HATS. With the goal.

  (1) In order to achieve the above object, the present invention takes the following measures. In other words, the call quality measurement method of the present invention is a reception quality measurement method for evaluating the acoustic transfer characteristics of an auricular vibration type receiver, the step of transmitting sound waves from the receiver for each frequency, and a head and torso simulator Recording the sound wave, obtaining a difference characteristic between the recorded sound wave and the transmitted sound wave, and correcting the recorded sound wave with the difference characteristic, after the correction It is characterized in that it is determined whether or not the sound wave satisfies a predetermined reference value.

  In this way, sound waves are transmitted from the handset for each frequency, sound waves are recorded via the head and torso simulator, differential data between the recorded sound waves and the transmitted sound waves are acquired, and the recorded sound waves are differential characteristics. Therefore, it is not necessary to perform subjective evaluation, which has been required in the past, for a mobile device equipped with an auricular vibration type receiver, and objective evaluation by HATS can be performed. As a result, it is possible to perform reception quality measurement with less time and cost than subjective evaluation.

  (2) Further, in the reception quality measuring method of the present invention, the difference characteristic adjusts the gain of the recorded sound wave so that the recorded sound wave has the same loudness as the transmitted sound wave. It is generated by this.

  In this way, the differential characteristic is generated by adjusting the gain of the recorded sound wave so that the recorded sound wave has the same loudness as the transmitted sound wave, so it is equipped with a pinna vibration type receiver Also for the mobile device, it is not necessary to perform subjective evaluation which has been conventionally required, and objective evaluation by HATS can be performed.

  (3) Further, the reception quality measuring device of the present invention is a reception quality measuring device for evaluating the acoustic transmission characteristics of the auricular vibration type receiver, which is transmitted from the receiver for each frequency and recorded via the head and torso simulator. An input unit for inputting the recorded sound wave, a processing unit for obtaining a difference characteristic between the recorded sound wave and the transmitted sound wave, and correcting the recorded sound wave with the difference characteristic, and the corrected sound wave Comprises a determination unit that determines whether or not a predetermined reference value is satisfied.

  In this way, sound waves are transmitted from the handset for each frequency, sound waves are recorded via the head and torso simulator, the difference characteristics between the recorded sound waves and the transmitted sound waves are acquired, and the recorded sound waves are difference characteristics Therefore, it is not necessary to perform subjective evaluation, which has been required in the past, for a mobile device equipped with an auricular vibration type receiver, and objective evaluation by HATS can be performed. As a result, it is possible to perform reception quality measurement with less time and cost than subjective evaluation.

  (4) Further, in the reception quality measuring apparatus of the present invention, the difference characteristic adjusts the gain of the recorded sound wave so that the recorded sound wave has the same loudness as the transmitted sound wave. It is generated by this.

  In this way, the differential characteristic is generated by adjusting the gain of the recorded sound wave so that the recorded sound wave has the same loudness as the transmitted sound wave, so it is equipped with a pinna vibration type receiver Also for the mobile device, it is not necessary to perform subjective evaluation which has been conventionally required, and objective evaluation by HATS can be performed.

  (5) Further, the program of the present invention is a program of a reception quality measuring device for evaluating the acoustic transfer characteristics of a pinna vibration type receiver, which is transmitted from the receiver for each frequency and recorded via a head and torso simulator. A process of inputting a sound wave, a process of obtaining a difference characteristic between the recorded sound wave and the transmitted sound wave, correcting the recorded sound wave with the difference characteristic, and a sound wave after the correction, Determining whether or not a predetermined reference value is satisfied, wherein the difference characteristic is such that the recorded sound wave has the same loudness as the transmitted sound wave. It is generated by adjusting the gain.

  In this way, sound waves are transmitted from the handset for each frequency, sound waves are recorded via the head and torso simulator, the difference characteristics between the recorded sound waves and the transmitted sound waves are acquired, and the recorded sound waves are difference characteristics Therefore, it is not necessary to perform subjective evaluation, which has been required in the past, for a mobile device equipped with an auricular vibration type receiver, and objective evaluation by HATS can be performed. As a result, it is possible to perform reception quality measurement with less time and cost than subjective evaluation.

  According to the present invention, it is not necessary to perform subjective evaluation, which has been conventionally required, for a mobile device equipped with an auricular vibration type receiver, and objective evaluation by HATS can be performed.

It is a figure which shows the whole concept of this embodiment. It is a block diagram which shows schematic structure of the reception quality measuring apparatus which concerns on this embodiment. It is a graph which shows the relationship between a frequency and a gain. It is a flowchart which shows operation | movement of the reception quality measuring apparatus which concerns on this embodiment. It is a figure which shows the example of a gain.

  In the present embodiment, a difference between a received sound via HATS (head and torso simulator) and a received sound directly heard by the operator is detected. For this purpose, a pure sound is reproduced for each frequency, and the sound that the same operator listens to with headphones through HATS is compared with the sound that is directly heard, and the gain is adjusted so that the sound pressure feels the same. Here, the difference between equal loudness curves and hearing loss for each operator is not included. In addition, the difference in the resonance frequency of the ear canal is reflected in the measurement result when the headphone characteristics are measured by HATS.

  FIG. 1 is a diagram showing an overall concept of the present embodiment. As shown in FIG. 1, a handset is attached to HATS. Next, a sound wave is transmitted from the handset for each frequency, and the sound wave is recorded via HATS. The frequency is, for example, “0.3, 0.5, 0.8, 1.0, 1.5, 2.0, 2.5, 3.0, 3.4 kHz” of the telephone band. Next, a person listens to the recorded sound wave with headphones.

  On the other hand, in FIG. 1, a sound wave is transmitted from the receiver for each frequency, and a person listens. At this time, the gain is adjusted until the volume of each sound becomes the same. Thereby, a gain as a correction characteristic is obtained. By using the gain and the headphone characteristics as the correction characteristics to correct the recorded sound wave via HATS, it is possible to obtain a sound to be evaluated.

  FIG. 2 is a block diagram showing a schematic configuration of the communication quality measuring apparatus according to the present embodiment. A sound wave (tone) for each frequency is input from the input unit 1. For example, a recorded sound wave can be used. The processing unit 3 acquires a correction characteristic as a difference characteristic between the recorded sound wave and the transmitted sound wave. FIG. 2 shows an example acquired as a low pass filter (LPF). FIG. 3 is a graph showing the relationship between frequency and gain. Here, “HATS” and “HATS, gain adjustment and headphone characteristics”, and their differences are shown. The “HATS” and “HATS, gain adjustment, and headphone characteristics” are graphs rising to the right depending on element characteristics. Further, when the HATS pinna is vibrated, the frequency characteristics are linear. On the other hand, the frequency characteristics when the human pinna is vibrated constitutes a low-pass filter.

  As shown in FIG. 3, the present inventors have found that this difference characteristic forms a low-pass filter. Therefore, the difference from the subjective evaluation can be eliminated by applying the low-pass filter based on the difference characteristic to the characteristic obtained by HATS. That is, the processing unit 3 shown in FIG. 2 corrects the recorded sound wave using the acquired difference characteristic. The determination unit 5 acquires a reference value and determines whether the corrected characteristic (evaluation target sound) satisfies the reference value. The display unit 7 displays the corrected characteristics and the determined characteristics.

  FIG. 4 is a flowchart showing the operation of the reception quality measuring apparatus according to this embodiment. In FIG. 4, Steps S1 to S11 show operations for acquiring the difference characteristics, and Steps T1 to T8 show operations for correcting the sound recorded through HATS with the difference characteristics. First, a sound wave is input for each frequency, and a differential characteristic is acquired for each frequency. The frequency is determined and started (step S1). Next, a tone (sound wave) is reproduced from the handset (step S2), and this is recorded by HATS (step S3). Here, a tone with a gain of 0 is obtained (step S4). Next, the tone recorded by the operator in step S3 is listened to with headphones (step S5). On the other hand, the operator listens to the tone reproduced in step S2 with the handset (step S6).

  Next, the tone heard with the headphones in step S5 is compared with the tone heard with the handset in step S6 to determine which volume is louder (step S7). If the volume of the headphones is higher, the gain is lowered (step S8), and the process proceeds to step S5. On the other hand, when the volume of the headphones is lower, the gain is increased (step S9), and the process proceeds to step S5.

  If the tone heard with the headphones in step S5 and the tone heard with the handset in step S6 have the same volume, the gain is written (step S10), and the measurement at that frequency is terminated (step S11).

  FIG. 5 is a diagram illustrating an example of the gain obtained in step S10. FIG. 5 shows gains and their average values in the handsets of three different types of mobile devices.

  Next, reception quality measurement using HATS is performed. Also here, a sound wave is input for each frequency, and a differential characteristic is acquired for each frequency. The frequency is determined and started (step T1). Next, a tone (sound wave) is reproduced from the handset (step T2) and recorded by HATS (step T3). Next, the gain (difference characteristic) obtained in step S10 is read (step T4). Here, for example, a gain as shown in FIG. 5 can be used. And the characteristic which shows a headphone characteristic is read (step T5), a difference correction is performed (step T6), and it outputs (step T7). Then, the measurement at that frequency is finished (step T8).

  Note that this embodiment can also be realized by causing a computer to execute a program. That is, the program according to the present embodiment is a program of a reception quality measuring device that evaluates the acoustic transfer characteristics of an auricular vibration type receiver, and is transmitted from the receiver for each frequency and recorded via a head and torso simulator. A process of inputting a sound wave, a process of obtaining a difference characteristic between the recorded sound wave and the transmitted sound wave, correcting the recorded sound wave with the difference characteristic, and the sound wave after the correction are predetermined. Determining whether the recorded reference value is satisfied, wherein the difference characteristic is a gain of the recorded sound wave so that the recorded sound wave has the same loudness as the transmitted sound wave. Is generated by adjusting

  As described above, according to the present embodiment, a sound wave is transmitted from the handset for each frequency, the sound wave is recorded via the head and torso simulator, and a difference characteristic between the recorded sound wave and the transmitted sound wave is acquired. In addition, since the recorded sound wave is corrected with the difference characteristic, it is not necessary to perform the subjective evaluation that has been required in the past even for a mobile device equipped with an auricular vibration type receiver, and it is possible to perform objective evaluation by HATS. It becomes. As a result, it is possible to perform reception quality measurement with less time and cost than subjective evaluation.

1 Input unit 3 Processing unit 5 Determination unit 7 Display unit

Claims (5)

A method for measuring reception quality for evaluating sound transmission characteristics of a pinna vibration type receiver,
Transmitting sound waves from the receiver for each frequency;
Recording the sound wave via a head and torso simulator;
Obtaining a differential characteristic between the recorded sound wave and the transmitted sound wave;
Correcting the recorded sound wave with the differential characteristic,
It is determined whether the corrected sound wave satisfies a predetermined reference value or not.   The differential characteristic is generated by adjusting a gain of the recorded sound wave so that the recorded sound wave has the same loudness as the transmitted sound wave. Listening quality measurement method. A receiving quality measuring device for evaluating the acoustic transfer characteristics of a pinna vibration type receiver,
An input unit for inputting sound waves transmitted from the receiver for each frequency and recorded via the head and torso simulator;
A processing unit that obtains a difference characteristic between the recorded sound wave and the transmitted sound wave, and corrects the recorded sound wave with the difference characteristic;
A reception quality measuring device comprising: a determination unit that determines whether the corrected sound wave satisfies a predetermined reference value.   The differential characteristic is generated by adjusting a gain of the recorded sound wave so that the recorded sound wave has the same loudness as the transmitted sound wave. Receiver quality measuring device. A program of a reception quality measuring device for evaluating the sound transmission characteristics of a pinna vibration type receiver,
A process of inputting sound waves transmitted from the receiver for each frequency and recorded via the head and torso simulator;
Obtaining a difference characteristic between the recorded sound wave and the transmitted sound wave, and correcting the recorded sound wave with the difference characteristic;
Determining whether the corrected sound wave satisfies a predetermined reference value,
The difference characteristic is generated by adjusting the gain of the recorded sound wave so that the recorded sound wave has the same loudness as the transmitted sound wave.

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