JP2004235737A - Communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid that, when a user talks using a communication apparatus in a place with surrounding noises, the received voice may be drowned out by the surrounding noises to make the talking hard. <P>SOLUTION: The communication apparatus comprises a microphone for collecting surrounding noises, a central processing unit for analyzing the surrounding noises and received voice filters fit to the surrounding noises. The received voice filters are switched over according to the surrounding noises to receive, thus enabling the talking without drowning the voice by the surrounding noises. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a communication device, and more particularly to an improvement in received speech intelligibility of a radio device.
[0002]
[Prior art]
In the prior art, a telephone call was performed with a fixed filter provided as a filter for audio signals on both the transmitting side and the receiving side irrespective of ambient noise.
[0003]
[Problems to be solved by the invention]
In the above-described conventional technology, since a fixed audio signal filter is always used, depending on the situation of the ambient noise, the received voice may be erased by the ambient noise, and a situation may occur in which a call becomes difficult. In the present invention, the received voice can be clearly heard without being turned off by the ambient noise.
[0004]
[Means for Solving the Problems]
To achieve the above object, the present invention includes a microphone that collects ambient noise separately from a microphone that collects an audio signal in a communication device, and includes a filter for a received audio signal having several different characteristics, The received sound signal filter is switched according to the noise collected by the ambient noise collecting microphone, so that the received sound can be heard clearly.
[0005]
More specifically, in a communication device, a microphone that collects noise such as voice that is unrelated to a call surrounding the receiving side during voice reception in a voice call, and a center signal from a noise signal around the receiving side collected by the microphone. A central processing unit for determining a frequency component to be, and according to the surrounding noise frequency component obtained by the central processing unit, the received voice signal received by the communication device is set to a frequency close to the ambient noise frequency component. Filter selecting means for selecting, switching, and filtering a filter to be emphasized; a plurality of filters having at least a flat characteristic, a high-frequency emphasis characteristic, and a low-frequency emphasis characteristic; and a reception for amplifying an output signal of the filter. It has an audio signal amplifier and a speaker.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to FIGS. The configuration of the wireless device will be described as an example with reference to FIG. 1 is a radio, 2 is a microphone for collecting sound, 3 is a microphone for collecting ambient noise, 4 is a modulator, 5 is a central processing unit, 6 is an antenna, 7 is a radio signal processor, 8 is a demodulator, 9- 1, 9-2, 9-3 are changeover switches, and 10-1, 10-2, 10-3 are audio signal filters for flat, high-frequency emphasis, and low-frequency emphasis, respectively. Reference numeral 11 denotes an adder, reference numeral 12 denotes an audio signal amplifier, reference numeral 13 denotes a speaker, and the audio collection microphone 2 is connected to the modulation unit 4 and is connected to the antenna 6 via the radio signal processing unit 7. The transmitting operation is similar to that of the current radio, and the voice collected by the voice collecting microphone 2 is band-limited by the converter 4, converted into a radio signal by the radio signal processor 7, and transmitted as a radio transmission wave via the antenna 6. You. Next, the configuration of the receiving unit will be described. The antenna 6 is connected to a demodulation unit 8 via a radio signal processing unit 7, and an output of the demodulation unit is connected to changeover switches 9-1, 9-2, and 9-3. The output of the adder 11 is connected to the speaker 13 via the audio signal amplifier 12 via the audio filters 10-1, 10-2 and 10-3. Further, the ambient noise collecting microphone 3 is connected via a central processing unit 5 to control signal terminals of the switches 9-1, 9-2, 9-3. In the operation of this receiver, the radio signal received by the antenna 6 is down-converted by the radio signal processing unit 7, demodulated into an audio signal by the demodulation unit 8, and sent to the switch 9. The control of the changeover switch 9 is performed by analyzing the frequency component of the ambient noise collected by the ambient noise collecting microphone by the central processing unit and using the optimum filter according to the ambient noise. , 9-3 are controlled so as to pass through one route from the filter (flat) 10-1, (high-frequency emphasis) 10-2, and (low-frequency emphasis) 10-3. The optimally filtered received audio signal output of the filter 10 is amplified by an audio signal amplifier 12 via an adder 11 and reproduced by a speaker 13. The characteristics of the filter used here will be described with reference to FIG. In the graph of FIG. 2, the X axis indicates frequency, and the Y axis indicates output level. For example, when there is no ambient noise, or when the ambient noise cannot be determined by the central processing unit 5 in FIG. 1, the filter 10-1 having a flat characteristic 14 is used, and when the ambient noise emits high-frequency noise, To enhance the high frequency of the received voice signal, the filter 10-2 having the characteristic 15 in which the high frequency is extended is selected. Conversely, when the ambient noise emits low frequency noise, the low frequency of the received voice is emphasized. For this purpose, a filter 10-3 having a characteristic 16 whose low range is extended is used. Although three types of filters have been described, the present invention is not limited to this, and there may be more filters. Note that the radio device of the press talk system does not receive a signal during transmission, so that the microphone for collecting sound and the microphone for collecting ambient noise can be shared. Needless to say, the present invention can be used not only for wireless but also for wired communication devices.
[0007]
【The invention's effect】
As described above, by switching the filter for the received voice according to the ambient noise situation on the receiving side, the voice component that is eliminated by the ambient noise can be emphasized, and the call can be clearly communicated. .
[Brief description of the drawings]
FIG. 1 is a block diagram showing one embodiment of the present invention.
FIG. 2 is a characteristic diagram showing an example of a filter characteristic in the embodiment of the present invention.
[Explanation of symbols]
1: wireless device, 2: microphone for collecting audio signal, 3: microphone for collecting ambient noise, 4: modulator, 5: central processing unit, 6: antenna, 7: wireless signal processor, 8: demodulator, 9: Changeover switch, 10: audio signal filter, 11: adder, 12: amplifier, 13: speaker, 14: normal received audio filter, 15: high-frequency emphasis audio signal filter, 16: low-frequency emphasis audio Signal filter, X: frequency, Y: filter output level.

Claims (1)

In communication equipment,
A microphone that converts noise around the receiving side into an electric signal while receiving the audio signal,
A central processing unit for obtaining the frequency component from noise around the receiving side converted into an electric signal by the microphone;
At least, a flat characteristic, a high-frequency emphasis characteristic, and a plurality of filters having a low-frequency emphasis characteristic,
Filter selection means for selecting a filter according to the obtained ambient noise frequency component,
A receiving audio signal amplifier for amplifying an output signal of the filter;
A speaker for converting the received audio signal amplified by the audio signal amplifier into audio, and filtering the audio signal with a frequency filter close to the ambient noise frequency component so that the audio signal is close to the ambient noise frequency component. A communication device characterized by frequency emphasis.

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