JP3416469B2 - base station - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base station wirelessly connected to a mobile phone terminal, and more particularly to a base station wirelessly connected to a PHS terminal.

[0002]

2. Description of the Related Art Conventionally, there has been known a mobile phone system in which a mobile phone terminal wirelessly connects through a plurality of base stations connected to a public network to make a call. In particular, the PHS is being put into practical use as a system in which a single mobile phone terminal can be used to make a call in all situations of homes, businesses, and outdoors. Here, when using a mobile phone terminal such as a PHS terminal, there is a problem that the other party's voice is difficult to hear during a call in an environment where ambient noise is large, such as at a station platform or in a factory. Therefore, a conventional mobile phone terminal such as a PHS terminal is provided with a function for adjusting the listening volume, and when the other party's voice is hard to hear due to ambient noise, the listening volume can be adjusted by performing a predetermined operation on the mobile phone terminal. Can be large.

As a conventional telephone device, as shown in Japanese Utility Model Laid-Open No. 6-2844, the ambient noise level of the telephone device is detected, and the received voice signal level to be sent to the receiving section is optimized according to the detected level. It is disclosed that the value is set. Further, the volume level of the voice data sent from the base station to the mobile phone terminal located within the wireless zone of the base station is usually set to a predetermined level. That is,
The volume is set so that it is easy for the receiving side to listen to in a quiet environment so that the volume is not too loud for the receiving side.

[0004]

However, when using the listening volume adjusting function provided in the portable telephone terminal, there is a problem in that the listening volume needs to be adjusted every time. In other words, when making a call, the caller listens to the ambient noise in advance and adjusts the listening volume before performing the outgoing call operation. Also, when receiving a call, similarly hears the ambient noise and adjusts the listening volume before performing the off-hook operation. I have to However, in particular, when there is an incoming call, since there is actually no such time margin, it is necessary to interrupt the conversation during the call to adjust the reception volume.

Further, according to the telephone device of Japanese Utility Model Laid-Open No. 6-2844, the ambient noise level is automatically detected and the received voice signal level to be transmitted to the receiving section is set to the optimum value. However, if the user wants to obtain the listening volume adjusting function as described above, he / she must use the mobile phone terminal having the above-mentioned configuration, and there is no such receiving voice level setting function. It is not possible to adjust the volume according to the ambient noise while using a conventional mobile phone terminal. Therefore, the present invention provides a technology capable of adjusting the reception volume of a mobile phone terminal such as a mobile phone according to ambient noise, and further, widely applying the reception volume adjustment to conventional mobile phone terminals. The purpose is to do.

[0006]

The present invention was created to solve the above problems. First, a base station connected to a public line network and wirelessly connected to a mobile phone terminal. The ambient noise detecting means for detecting the level of ambient noise in the mobile telephone terminal, and the volume level of the audio signal to the mobile telephone terminal are adjusted according to the ambient noise detected by the ambient noise detecting means. And a volume control means. In the base station of the first configuration, the ambient noise detecting means detects the level of ambient noise in the mobile phone terminal. Then, the volume control means adjusts the volume level of the audio signal to the mobile phone terminal according to the ambient noise detected by the ambient noise detection means. Therefore, since the volume level is adjusted according to the ambient noise of the mobile phone terminal, the caller can surely hear the voice of the other party. Also, since the volume level of the audio signal is adjusted in the base station, it can be widely applied to all mobile phone terminals wirelessly connected to the base station without depending on the function of the mobile phone terminal wirelessly connected to the base station. it can.

Secondly, in the above-mentioned first construction, the ambient noise detecting means is adapted to carry the mobile phone for a predetermined time after the line between the mobile phone terminal and the other party of the call is connected to form a communication path. The feature is that the level of ambient noise is detected by a voice signal input from a telephone terminal. Therefore, if the predetermined time is set to a short time, it is possible to detect the ambient noise by picking up the voice before the caller starts speaking. Thirdly, in the first or second configuration, the ambient noise detecting means includes a digital-analog converter for converting a digital voice signal transmitted from a mobile phone terminal into an analog voice signal, and an analog voice. It has a comparison part which compares the voltage value of a signal and a reference voltage value, and outputs the noise level signal according to the comparison result. In the base station having the third configuration, the digital / analog conversion unit converts the digital voice signal transmitted from the mobile phone terminal into an analog voice signal. Then, the comparison unit compares the analog audio signal with the reference voltage value and outputs a predetermined noise level signal. Therefore, the noise level of ambient noise can be detected.

Fourthly, in the third configuration, the volume control means converts the digital audio signal to the portable telephone terminal into an analog audio signal, and a digital-analog conversion section. An amplifier for amplifying an analog audio signal transmitted from the amplifier, and an amplifier for switching between amplification processing and / or amplification according to the noise level signal, and an analog audio signal from the amplifier. And an analog / digital converter for converting into a digital audio signal. In the base station of the fourth configuration, the digital / analog converter is
Converts a digital audio signal to a mobile phone terminal into an analog audio signal. Then, the amplification unit performs amplification processing of the analog audio signal. At that time, the presence / absence of amplification processing and / or the switching of the amplification factor are performed according to the noise level signal. Then, the analog / digital converter converts the analog audio signal from the amplifier into a digital audio signal. Therefore, the volume level can be adjusted according to the noise level signal.

Fifth, it is connected to a public line network,
An ambient noise detecting means for detecting a level of ambient noise input from the maintenance terminal or the mobile phone terminal, which is a base station having a function of connecting to the mobile phone terminal by wireless and having a connection function with the maintenance terminal. Volume setting means for setting the volume level of the audio signal to the mobile telephone terminal in which the communication path is formed, according to the ambient noise detected by the ambient noise detecting means. In the base station of the fifth configuration, the ambient noise detecting means detects the level of ambient noise input from the maintenance terminal or the mobile phone terminal. Then, the volume setting means sets the volume level of the audio signal to the mobile phone terminal in which the communication path is formed, according to the ambient noise detected by the ambient noise detecting means. Therefore, at the stage of installing the base station, it is possible to set the volume level in consideration of ambient noise in advance, and increase the volume level when installing the base station in a place with large ambient noise such as a station platform or factory. Can be installed. Moreover, since the volume level of the base station is set in advance, a complicated circuit configuration is not necessary.

Sixthly, in the fifth configuration, the ambient noise detecting means converts the digital voice signal transmitted from the maintenance terminal or the mobile telephone terminal into an analog voice signal into a digital-analog converter. And a comparison unit that compares the voltage value of the analog audio signal with the reference voltage value and outputs a noise level signal according to the comparison result. In the base station of the sixth configuration, the digital / analog converter converts the digital voice signal transmitted from the mobile phone terminal into an analog voice signal. Then, the comparison unit compares the analog audio signal with the reference voltage value and outputs a predetermined noise level signal. Therefore, the noise level of ambient noise can be detected. Seventhly, in the sixth configuration, the volume control means converts the digital audio signal to the mobile phone terminal in which the communication path is formed into an analog audio signal.
The analog conversion section and the amplification section in which the presence / absence of amplification processing and / or the amplification factor are preset by the volume setting means according to the noise level signal
It is characterized in that it has an amplification section for processing the analog audio signal transmitted from the analog conversion section, and an analog-digital conversion section for converting the analog audio signal from the amplification section into a digital audio signal. In the base station of the seventh configuration, the digital / analog conversion unit converts a digital voice signal to the mobile phone terminal into an analog voice signal. Then, the amplification unit performs amplification processing of the analog audio signal. The amplification unit switches presence / absence and / or amplification factor of the volume setting means amplification processing according to the noise level signal. Then, the analog / digital converter converts the analog audio signal from the amplifier into a digital audio signal. Therefore, the volume level can be adjusted according to the noise level signal.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. The base station 10 according to the first embodiment of the present invention is a so-called PHS base station, is connected to the public line 70, and is a PH as a mobile phone terminal.
Wireless communication is performed with the S terminal 60. This base station 10 is shown in FIG.
As shown in, the antenna unit 12, the RF unit 14,
π / 4DQPSK modulator / demodulator (hereinafter referred to as “modulator / demodulator”)
16, TDMA / TDD processing unit 18, ADPCM /
The PCM converter 20, the upstream voice monitor 22, the line controller 24, the downstream voice volume controller 26, and the ROM 28.
And a RAM 30 and a CPU 32.

Here, the RF unit 14 is the antenna unit 1.
Wireless processing such as frequency conversion of a reception signal received via the wireless communication terminal 2 is performed. Further, the modulation / demodulation unit 16 uses the RF
The TDMA is performed by demodulating the digital modulation signal from the unit 14.
/ TDD processing unit 18 and outputs to TDMA / T
The carrier wave is modulated by the digital signal from the DD processing unit 18 and output to the RF unit 14. Further, the TDMA / TDD processing unit 18 performs transmission path access control according to the TDMA / TDD method. In addition, the ADPCM / PCM conversion unit 20
Decompresses the digital audio signal sent from the TDMA / TDD processing unit 18, that is, the digital audio signal data-compressed by the ADPCM system, into the original digital audio signal and transmits the original digital audio signal to the upstream audio monitoring unit 22, while Digital audio data from the audio volume control unit 26 is ADPCM
It is compressed by the method and transmitted to the TDMA / TDD processing unit 18.

The upstream voice monitor unit 22 as ambient noise detecting means monitors the ambient noise around the portable telephone terminal and outputs a noise level signal indicating the ambient noise level to C.
It is transmitted to the PU 32. The detailed configuration of the upstream voice monitor unit 22 will be described later. In addition, the line control unit 24
Is connected to the public line 70 and controls the line of the public line. In addition, the downlink voice volume control unit 26 displays C
The downlink audio signal is subjected to predetermined processing by the amplification control signal from the PU 32 and output to the ADPCM / PCM conversion unit 20. The detailed configuration of the downlink voice volume control unit 26 will be described later.

The ROM 28 stores various information for operating the base station 10. In particular, the ROM 28 outputs a predetermined amplification control signal in accordance with a noise level signal from the upstream voice monitor unit 22 and a downstream voice volume control unit 26. The program for outputting to is stored. In addition, the RAM 30 is for writing and reading various information for operating the base station 10. Further, the CPU 32 controls the operation of each unit in the base station 10, and particularly outputs a predetermined amplification control signal corresponding to the noise level signal from the upstream voice monitor unit 22 in accordance with the program stored in the ROM 28. To do. At least the downlink voice volume control unit 26 functions as volume control means.

Next, the configuration of the upstream voice monitor section 22 will be described. As shown in FIG. 2, the upstream voice monitor unit 22 includes a digital / analog converter 22a and a smoother 2
2b and a comparator 22c. Here, the digital / analog converter 22a serving as the digital / analog converter converts the digital audio signal transmitted from the ADPCM / PCM converter 20 into an analog audio signal. Specifically, a digital audio signal for a predetermined time from the time when the line is connected between the transmitting side and the receiving side is converted into an analog signal. This predetermined time is several msec or tens of m
It is a short time of sec. The smoother 22b averages the analog audio signal from the digital-analog converter 22a and outputs it as a voltage value. That is, the analog audio signals for the predetermined time are averaged and output. Also,
The comparator 22c serving as the comparison unit includes a smoother 22b.
Output and the reference voltage, and according to the comparison result,
A predetermined noise level signal is output. That is, when the output voltage of the smoother 22b is higher than the reference voltage, High is output as a noise level signal, and when the reference voltage is higher, Low is output.

Next, the downlink voice volume control section 26 will be described. As shown in FIG. 3, the downlink sound volume control unit 26 has a digital / analog converter 26a, an amplifier 26b, and an analog / digital converter 26c. Here, the digital / analog converter 26a as the digital / analog converter is the line controller 2
The digital voice signal transmitted from the No. 4 is converted into an analog voice signal. In addition, the amplifier 26 as the amplification unit
b is in accordance with the amplification control signal transmitted from the CPU 32,
The analog audio signal output from the digital-analog converter 26a is amplified. The amplifier 26b has a through mode and an amplification mode. When the amplification control signal from the CPU 32 is High, the amplification mode amplifies the analog signal and outputs it to the analog-digital converter 26c. When the amplification control signal is Low, the analog audio signal output from the digital-analog converter 26a is sent to the analog-digital converter 26c as it is in the through mode. The amplifier 26b is initially set to the through mode. Further, the analog / digital converter 26c as the analog / digital converter converts the analog audio signal output from the amplifier 26b into a digital audio signal to perform ADPCM.
It is output to the / PCM conversion unit 20.

The operation of the base station 10 having the above configuration will be described. First, the case where a call request is issued from the PHS terminal 60 will be described. The PHS terminal 60 is assumed to be in the wireless zone of the base station 10. In this case, line connection is performed according to the procedure shown in FIG. That is, the PHS terminal 6
When the link channel probability request is made from the 0 side (S1
0), link channel allocation is performed from the base station (S11). Then, transmission / reception of the synchronization burst (S12,
After S13), call setting (S14) and call setting acceptance (S1)
5), after calling (S16), reply (S1
7) is transmitted from the base station 10 to the PHS terminal 60. By this response, the line is connected and a speech path is formed. That is, when the line is connected, the call becomes possible.

Here, when it is detected that the response (S17) is made from the base station 10, the CPU 32 sends a conversion start signal to the digital / analog converter 2 of the upstream voice monitor section 22.
2a. Then, the digital-analog converter 2
2a converts a digital audio signal for a predetermined time from the time when the line is connected to an analog audio signal. That is, the voice signal input from the microphone provided in the PHS terminal 60 on the transmitting side is transmitted to the RF unit 14, the modulation / demodulation unit 16, and the TDMA / T.
It is sent to the upstream voice monitor unit 22 via the DD processing unit 18 and the ADPCM / PCM conversion unit 20, input to the digital / analog converter 22a, and converted into a digital voice signal.

Here, the predetermined time is an extremely short time of several msec or tens of msec. That is, the voice signal transmitted from the PHS terminal 60 is monitored during a short short time after the line is connected until the caller starts speaking. That is, the voice signal converted by the digital / analog converter 22a becomes ambient noise around the PHS terminal 60. That is, the monitored voice signal does not include the voice data of the caller.
Next, the smoother 22b is the digital-analog converter 22.
The analog audio signal from a is averaged and output in the form of a voltage value. Then, the comparator 22c compares the output of the smoother 22b with the reference voltage, and outputs a predetermined noise level signal according to the comparison result. That is, the smoother 2
When the output voltage of 2b is higher than the reference voltage, High is output as a noise level signal, and when the reference voltage is higher, Low is output. That is, the PHS terminal 60
If the ambient noise of is above a certain level, High
Is output, on the other hand, when it is less than the certain level, Lo is output.
w will be output.

Then, the CPU 32 transmits an amplification control signal to the downlink sound volume control unit 26 according to the noise level signal according to the program stored in the ROM 28. That is, when the noise level signal is High, High
Output the amplification control signal, while the noise level signal is Lo
In the case of w, a Low amplification control signal is output.

Then, the amplifier 26b amplifies the analog audio signal output from the digital-analog converter 26a according to the amplification control signal. That is, the other party's P
The digital voice signal from the HS terminal 80 is sent to the line control unit 2
4 is transmitted to the digital / analog converter 26a of the downlink sound volume control unit 26, and the digital / analog converter 26
At a, it is converted into an analog audio signal and sent to the amplifier 26b. The amplifier 26b receives the amplification control signal Hi.
In the case of gh, the analog audio signal is amplified in the amplification mode. The amplification factor is, for example, 3dβ (decibel). On the other hand, when the amplification control signal is Low, the digital / analog converter 26 is set to the through mode.
The analog control signal from a is directly transmitted to the analog / digital converter 26c. Then, the analog-digital converter 26c converts the analog voice signal into a digital voice signal and outputs the digital voice signal to the ADPCM / PCM conversion unit 20.

Then, the voice signal from the PHS terminal 80 is processed by the TDMA / TDD processing unit 18, the modulation / demodulation unit 16, R.
It is sent to the PHS terminal 60 via the F section 14. In the PHS terminal 60, when the audio signal is amplified by the amplifier 26b, the volume level becomes high and it is heard.

In the above description, the case of making a call from the PHS terminal 60 has been described, but the same applies to the case of making a call at the PHS terminal 60. That is, P
When an incoming call is received at the HS terminal 60, line connection is performed according to the procedure shown in FIG. That is, from the base station 10 to PH
When an incoming signal is transmitted to the S terminal 60 (S20), PH
A link channel probability request is made from the S terminal 60 side (S
21), the link channel is allocated from the base station (S22). Then, the transmission and reception of the synchronization burst (S23,
After S24, an incoming call response (S25) and a call setup (S2)
6) After the call setting acceptance (S27), the call (S28), and the response (S29), the response confirmation (S30) is transmitted from the base station 10 to the PHS terminal 60. Upon confirmation of this response, the line is connected and a speech path is formed. That is,
Once the line is connected, you can talk.

When the line is connected, the processing is performed in the same manner as in the above case. That is, the voice signal from the PHS terminal 60 is monitored for a predetermined time after the line is connected, the ambient noise level is detected, and the voice signal from the PHS terminal 80 to the PHS terminal 60 is detected according to the ambient noise level. Adjust the volume level of.

The amplification factor set in the amplifier 26b is effective only for a call connected to the line, and returns to the initial through mode when the line is disconnected. Therefore, PH
When an outgoing / incoming call is made again in the S terminal 60 within the wireless zone of the base station 10, the volume level of the downlink signal is adjusted based on the ambient noise even when the line is connected, as described above. Become. In other words, if the line is disconnected,
The CPU 32 sends a Low amplification control signal to the amplifier 26b, and based on this, the amplifier 26b returns to the through mode. Also, when a plurality of PHS terminals are wirelessly connected to the base station 10 within the wireless zone of the base station 10, each PHS
The volume level of each S terminal is adjusted according to the ambient noise.

As described above, according to the base station of the present embodiment, the level of ambient noise of the PHS terminal is detected, and the reception volume is changed according to this level. You can definitely hear. In particular, since the volume of the ambient noise is detected by detecting the ambient noise for a moment after the line is connected, the volume can be adjusted according to the ambient noise level during the call. Further, in this embodiment, since the volume level of the audio signal is adjusted in the base station, it does not depend on the function of the mobile phone terminal wirelessly connected to the base station and is widely applied to the mobile phone terminal wirelessly connected to the base station. can do.

In the above description, the adjustment of the sound volume level has two steps, that is, amplification and non-amplification.
The volume may be adjusted to three or more levels. That is, a plurality of reference voltages are prepared and a plurality of amplification factors are prepared, and the volume level is adjusted according to the level of ambient noise. In the above description, the volume level is adjusted by the ambient noise for a moment after the line is connected.However, the so-called silent state in which the caller is not speaking is detected, and the ambient noise in that state is detected. You may make it detect each time and adjust a volume level.

Further, in the above description, the digital audio signal is converted into the analog audio signal and the ambient noise is detected by the output level, but the method of detecting the ambient noise is not limited to this, and the PHS is not limited thereto. This may be done by monitoring a predetermined bit indicating the level of the digital audio signal in the digital audio signal from the terminal 60. That is, the ambient noise is detected by monitoring the digital audio signal in the state of the digital signal. Further, in the above description, the digital audio signal is converted into the analog audio signal, and the volume level is adjusted by amplifying the analog audio signal by the amplifier. However, a predetermined volume indicating the volume level of the digital audio signal is adjusted. The volume level may be adjusted by processing the bit information. That is, by adjusting the volume level in the form of digital audio data, the downstream audio may be digitally processed to control the level.

When the PHS terminal 60 leaves the wireless zone of the base station 10, the volume adjustment control for a predetermined communication path is naturally stopped. When the PHS terminal is handed over from another base station to the base station 10, ambient noise may be detected at the time of the handover and the volume level may be adjusted. Further, the present invention is not limited to the above configuration, and may be any one that detects ambient noise around the PHS terminal and adjusts the volume level of the downlink audio signal according to the level of this ambient noise.

Next, the second embodiment will be described. In the second embodiment, the volume level of the downlink signal is set at the stage of installing the base station. That is, the base station 110 according to the present embodiment has substantially the same configuration as the base station 10 according to the first embodiment described above, and the antenna unit 112, the RF unit 114, and π /
4DQPSK modulator / demodulator (hereinafter referred to as "modulator / demodulator") 11
6, TDMA / TDD processing unit 118, ADPCM /
PCM conversion unit 120, line control unit 124, downlink sound volume control unit 126, ROM 128, RAM 130
, CPU 132, audio monitor unit 134, RS-2
The 32C control unit 136 is included. This base station 110
Is connected to the login terminal 150 via the connector 138.

Here, the antenna section 11 in the present embodiment.
2, an RF unit 114, a modulation / demodulation unit 116, and TDMA /
TDD processing unit 118 and ADPCM / PCM conversion unit 12
0 means the antenna unit 12 in the first embodiment and R
The F unit 14, the modulation / demodulation unit 16, the TDMA / TDD processing unit 18, and the ADPCM / PCM conversion unit 20 have substantially the same configuration. The ADPCM / PCM conversion unit 12
0 indicates the expanded digital audio signal to the line control unit 124.
Send to.

Further, as in the case of the first embodiment, the downlink sound volume control section 126 includes a digital / analog converter 126a, an amplifier 126b, and an analog / digital converter 126c, as shown in FIG. have. Here, the digital-analog converter 126a serving as the digital-analog converter converts the digital audio signal transmitted from the line controller 124 into an analog audio signal. Further, the amplifier 126b serving as the amplification unit.
According to the amplification control signal transmitted from the CPU 132,
The analog audio signal output from the digital-analog converter 126a is amplified. The amplifier 126b has a through mode and an amplification mode. When the amplification control signal from the CPU 132 is High, the analog signal is amplified in the amplification mode to amplify the analog / digital converter 12.
6c, and when the amplification control signal is Low, the digital-analog converter 12 is set to the through mode.
The analog audio signal output from 6a is sent to the analog / digital converter 126c as it is. Unlike the first embodiment, the amplifier 126b is fixed in the set mode after being set to either the through mode or the amplification mode at the installation stage of the base station 110. The analog / digital converter 126c as the analog / digital converter converts the analog audio signal output from the amplifier 126b into a digital audio signal,
It is output to the DPCM / PCM conversion unit 120.

The ROM 128 stores various information for operating the base station 110, and particularly stores a program for outputting an amplification control signal in accordance with ambient noise based on voice data from the login terminal 150. ing. In addition, the RAM 130 is for writing and reading various information for operating the base station 110. Further, the CPU 132 controls the operation of each unit in the base station 110, and particularly, the ROM 1
According to the program stored in 28, the login terminal 15
A predetermined amplification control signal is output according to the ambient noise based on the voice data from 0. At least the downlink voice volume control unit 126 functions as volume setting means.

Further, the voice monitor section 134 as the ambient noise detecting means monitors the ambient noise based on the voice data from the login terminal 150, and is the same as the upstream voice monitor section 22 in the first embodiment. In addition, it has a digital-analog converter as the digital-analog converter, a smoother, and a comparator as the comparator. Further, the RS-232C control unit 136 controls communication with the login terminal 150 connected via the connector 138. This login terminal 150
Is a terminal used for maintenance of the base station 110.
The login terminal 150 has a microphone and has a function of transmitting voice data of a voice collected from the microphone.

The operation of the base station 110 based on the above configuration will be described. When installing the base station 110, the login terminal 1
50 is connected to the connector 138 of the base station 110. Then, the surrounding voice is input from the microphone provided in the login terminal 150. At that time, the voice of the operator is not input.
That is, ambient noise of the login terminal 150 is input. The ambient sound data of the collected ambient sound is transmitted to the base station 110. The login terminal 150 and RS-2
Communication between the 32C control units 136 is performed by the RS-232C control unit 136. Then, this ambient voice data is sent to the voice monitor unit 134, and the level of ambient noise is detected. That is, after being converted into an analog signal by the digital / analog converter provided in the audio monitor unit 134, it is smoothed by the smoother and compared with the reference voltage by the comparator. Then, when the voltage value of the ambient audio data is higher than the reference voltage, a high noise level signal is output to the CPU 132. On the other hand, when the voltage value of the ambient audio data is lower than the reference voltage, the low noise level signal is output.

Then, the CPU 132 sends an amplification control signal to the downlink sound volume control unit 126 according to the noise level signal according to the program stored in the ROM 128. That is, when the noise level signal is High, H
When the noise level signal is low, the low amplification control signal is output.

Then, the amplifier 126b sets either the through mode or the amplification mode according to the amplification control signal. That is, when the amplification control signal is High, the amplification mode is set, while when the amplification control signal is Low, the through mode is set. This setting is for base station 1
It shall be fixed at 10. In other words, the volume of the subsequent calls is controlled according to this mode.

Then, the PHS terminal 160 and the PHS terminal 1
In a call between 80, the digital voice signal from the PHS terminal 180 is transmitted from the line control unit 124 to the digital / analog converter 126a of the downlink voice volume control unit 126, and is converted into an analog voice signal by the digital / analog converter 126a. It is converted and sent to the amplifier 126b. Then, the amplifier 126b amplifies the analog audio signal when the amplifier 126b is set in the amplification mode. The amplification factor is, for example, 3dβ (decibel). On the other hand, when the amplifier 126b is set to the through mode, the analog control signal from the digital / analog converter 126a is directly transmitted to the analog / digital converter 126c. Then, the analog-to-digital converter 126c converts the analog voice signal into a digital voice signal and outputs it to the ADPCM / PCM conversion unit 120. Then, the audio signal from the PHS terminal 180 is transmitted to the TDMA / TDD processing unit 118, the modulation / demodulation unit 116,
It is sent to the PHS terminal 160 via the RF unit 114. PH
In the S terminal 160, when the audio signal is amplified by the amplifier 126b, the volume level becomes high and the user can hear it.

As described above, according to the base station of the present embodiment, when the base station is installed, the level of ambient noise around the base station is detected and the mode of the amplifier 126b is set according to this level. The person can surely hear the voice of the other party. Therefore, when the base station is installed in a place where the ambient noise is large, such as a platform of a station or a factory, the volume level can be increased by setting the mode of the amplifier 126b in advance to the amplification mode. Further, since the mode of the amplifier is once set and fixed, the circuit configuration can be simplified as compared with the case of the first embodiment. Further, in this embodiment,
Since the volume level of the audio signal is adjusted at the base station,
The present invention can be widely applied to mobile phone terminals wirelessly connected to the base station without depending on the function of the mobile phone terminal wirelessly connected to the base station.

In the above description of the second embodiment, the adjustment of the volume level has two steps, that is, the case of amplifying the volume level and the case of not amplifying the volume level. However, even if the volume level can be adjusted to three or more levels. Good. That is, a plurality of reference voltages in the audio monitor unit 134 are prepared, and a plurality of amplification factors of the amplifier 126b are prepared, and the volume level is adjusted according to the level of ambient noise.

In the above description of the second embodiment, the volume level is adjusted by converting the digital audio signal into an analog audio signal and amplifying the analog audio signal with an amplifier. The volume level may be adjusted by processing the information of a predetermined bit indicating the volume level. That is, by adjusting the volume level in the form of digital audio data, the downstream audio may be digitally processed to control the level.

The following method can be considered as a method of adjusting the volume level at the stage of installing the base station. That is, the configuration of the base station is as shown in FIG. 1, and the amplification factor of the amplifier 26b is adjusted and fixed at the stage of installing the base station. In other words, from a point in the zone of the base station to P
The originating operation is performed from the HS terminal 60. Then, the upstream voice monitor unit 22 monitors the voice data for a short time after the line is connected, and the upstream voice monitor unit 22 outputs a noise level signal of either High or Low to the CPU 3
Output to 2. Then, the CPU 32 outputs the amplification control signal to the downlink audio volume control unit 26, which causes the amplifier 2 to operate.
The mode of 6b is set and fixed according to the amplification control signal. As a result, the volume of subsequent calls will be set according to the fixed mode.

Further, in the above description, the login terminal 15
The communication between 0 and the base station 110 is described as being performed by RS-232C, but the present invention is not limited to this and may be performed by optical space communication such as infrared communication. Further, the invention of the present embodiment is not limited to the above-mentioned configuration, and detects ambient noise around the base station installation stage and adjusts and fixes the volume level of the downlink voice signal according to the level of this ambient noise. Anything will do.

Further, the upstream voice monitor unit 22 and the downstream voice volume control unit 26 in the first embodiment may be constituted by a DSP (digital signal processor). Similarly, the audio monitor unit 134 and the downlink audio volume control unit 126 in the second embodiment may be configured by DSP. In this case, the processing speed can be increased. Also,
In each of the above embodiments, the PHS terminal is described as an example, but the present invention is not limited to this, and another mobile phone terminal may be used.

[0045]

According to the base station of the present invention, the volume level is adjusted according to the ambient noise of the portable telephone terminal.
The caller can surely hear the voice of the other party. Also,
Since the volume level of the audio signal is adjusted at the base station,
The present invention can be widely applied to all mobile phone terminals wirelessly connected to the base station without depending on the function of the mobile phone terminal wirelessly connected to the base station. Further, in particular, according to the base station of the second aspect, ambient noise can be detected by picking up the voice before the caller starts speaking. Further, in particular, according to the base station of claim 5, at the stage of installing the base station, the volume level can be set in consideration of ambient noise in advance, and the location such as a platform of a station or a factory has a large ambient noise. When installing the base station in, it is possible to increase the volume level. Moreover, since the volume level of the base station is set in advance, a complicated circuit configuration is not necessary.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a base station according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an upstream voice monitor unit.

FIG. 3 is a block diagram showing a configuration of a downlink voice volume control unit.

FIG. 4 is a sequence diagram showing an operation when a PHS terminal makes a call.

FIG. 5 is a sequence diagram showing an operation when a PHS terminal receives an incoming call.

FIG. 6 is a block diagram showing the configuration of a base station according to the second embodiment of the present invention.

[Explanation of symbols]

10,110 Base station 12,112 Antenna part 14, 114 RF section 16, 116 π / 4DQPSK modulator / demodulator 18, 118 TDMA / TDD processing unit 20,120 ADPCM / PCM converter 22 Upstream voice monitor 22a, 26a, 126a Digital-to-analog converter 22b smoother 22c comparator 24,124 Line control unit 26, 126 Downstream audio volume control unit 26b, 126b amplifier 26c, 126c analog-digital converter 28, 128 ROM 30,130 RAM 32, 132 CPU 60, 80 PHS terminals 70 public line 134 Audio monitor 136 RS-232C controller 150 login terminals

Claims (7)

(57) [Claims] 1. A base station which is connected to a public line network and wirelessly connects to a mobile phone terminal, the ambient noise detecting means detecting a level of ambient noise in the mobile phone terminal, and the ambient noise detecting means. Volume control means for adjusting the volume level of a voice signal to the mobile phone terminal according to the detected ambient noise. 2. The ambient noise detecting means detects ambient noise by a voice signal input from the mobile phone terminal for a predetermined time after the line between the mobile phone terminal and the other party of the call is connected and a call path is formed. The base station according to claim 1, wherein a level is detected. 3. The ambient noise detecting means compares a voltage value of the analog voice signal with a reference voltage value, and a digital-analog converter for converting the digital voice signal transmitted from the mobile phone terminal into an analog voice signal. hand,
The base station according to claim 1 or 2, further comprising: a comparison unit that outputs a noise level signal according to the comparison result. 4. The volume control means converts a digital voice signal to the mobile phone terminal into an analog voice signal, and an amplifier for amplifying the analog voice signal transmitted from the digital / analog converter. An amplification section for performing the presence / absence of amplification processing and / or switching of the amplification factor according to the noise level signal, and an analog / digital conversion section for converting the analog audio signal from the amplification section into a digital audio signal. The base station according to claim 3, comprising: 5. A base station which is connected to a public line network, wirelessly connects to a mobile phone terminal, and has a function of connecting to a maintenance terminal, the surroundings being input from the maintenance terminal or the mobile phone terminal. Ambient noise detecting means for detecting the level of noise, and volume setting means for setting the volume level of a voice signal to a mobile phone terminal in which a communication path is formed in accordance with the ambient noise detected by the ambient noise detecting means. A base station having: 6. A digital-analog converter for converting the digital audio signal transmitted from a maintenance terminal or a mobile phone terminal into an analog audio signal by the ambient noise detecting means, and a voltage value and a reference voltage value of the analog audio signal. Compare with
The base station according to claim 5, further comprising a comparison unit that outputs a noise level signal according to the comparison result. 7. A digital-analog converter for converting a digital voice signal to a mobile telephone terminal in which the communication path is formed into an analog voice signal by the volume control means, and the volume according to the noise level signal. An amplification unit in which the presence or absence and / or the amplification factor of amplification processing is preset by the setting means, and according to the setting, an amplification unit that processes the analog audio signal transmitted from the digital-analog conversion unit, and the amplification unit The base station according to claim 6, further comprising: an analog-digital conversion unit that converts an analog voice signal into a digital voice signal.