JPH03232349A - Radio telephone system - Google Patents

Abstract

PURPOSE:To prevent a radio telephone system from being complicated and further to prevent a control tone from being mixed into a sound to be outputted by detecting a control signal in a sound signal, removing the control signal from the sound signal by replacement or attenuation, etc., and transmitting the control signal in a sound band. CONSTITUTION:While control data is not detected by a control data detecting means 8a, a signal replacing means 8b of a control part 8 successively reads out sound data S3, which is stored in a sound data memory 9, and applies the data to a PCM decoder 10 while delaying the data for prescribed time from writing. When the control data is detected by the control data detecting means 8a, the signal replacing means 8b replaces a part corresponding to the control data in the sound data S3, which is stored in the sound data memory 9, with data at a silent level, namely, with the data of '0', afterwards, reads out the replaced data from the sound data memory 9 and applies it to the PCM decoder 10. Thus, the control tone is not outputted from a receiver 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention (Industrial Application Field) The present invention relates to a wireless telephone such as a cordless telephone device, which is applied to a wireless telephone system that transmits a control signal by superimposing it on a voice signal. Regarding equipment.

(Prior art) Cordless telephones have a fixed unit (base unit) and a mobile unit (base unit).
For example, a preamble signal is sent between the base unit and the slave unit in order to establish a control protocol with the slave unit.

It sends and receives control signals such as frame synchronization signals, ID signals, and cordless e-mail confirmation signals. Here, the control signal is transmitted using the same band as the audio signal. That is, the control signal is superimposed on the audio signal.

Therefore, the control signal output from the base unit to the slave unit is output as voice from the handset of the slave unit, and the control signal output from the slave unit to the base unit is transmitted to the communication partner terminal via the line. and output as voice from the handset of the communication partner's terminal.

The sound emitted by the control signal (control sound) sounds unpleasant to humans, and has the disadvantage of causing discomfort to the user.

In order to solve the above-mentioned disabling noise, the following measures have been considered.

■ Increase the modulation speed and shorten the control sound generation time.

■ Transmit control signals outside the audio band.

However, with method (■) above, the modulation speed is limited to about 4800 bps due to legal regulations and reliability.
Control sounds cannot be completely removed. Also above (
With method D, analog countermeasures such as spurious are required due to legal restrictions such as channel separation, which increases the number of circuits and reduces the transmission speed. Therefore, control sound removal using these methods is not very effective.

(Problems to be Solved by the Invention) As described above, in conventional radio telephone devices, it is not possible to completely eliminate the control sound, and in order to completely eliminate the control sound, the transmission speed of the control signal must be reduced or the circuit There were problems such as an increase in

The present invention has been made in consideration of these circumstances, and its purpose is to completely prevent the output of control sound with a relatively simple structure, and to also reduce the transmission speed of control signals. The purpose of the present invention is to provide a wireless telephone device without any

[Configuration of the Invention (Means for Solving the Problems) The first invention of the present application includes a control signal detection means for detecting a control signal superimposed on a received signal, and a control signal detected by the control signal detection means. The portion of the received audio signal that corresponds to the control signal is replaced with a predetermined signal such as a zero level signal or a natural noise signal.

The second invention of the present application is provided with a control signal detecting means for detecting a control signal superimposed on a received audio signal, and the control signal (in the received audio signal corresponding to the control signal detected by the i-detecting means) is provided. The part of the image is now attenuated.

The third invention provides a control signal detection means for detecting a control signal superimposed on a received audio signal, and a portion of the received audio signal corresponding to the control signal detected by the control signal detection means. Both the stationary device and the moving device are provided with a signal replacement means for replacing the signal with a predetermined signal.

A fourth invention of the present application provides a control signal detection means for detecting a control signal superimposed on a received audio signal, and a portion of the received audio signal corresponding to the control signal detected by the control signal detection means. Both the front fixing device and the moving device are provided with signal attenuation means for attenuating the signal.

(Function) By taking the measures described in 2 above, the control signal portion in the received audio signal is detected, and the signal of the portion is replaced with a predetermined signal or attenuated. Therefore, the control signal is removed from the audio signal and is not output as audio from the receiver or the like.

(Embodiment) Hereinafter, a wireless telephone device according to an embodiment of the present invention will be described as applied to a cordless telephone device with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the cordless telephone device. In the figure, 1 is a transmitter that converts voice into an audio signal. The audio signal output from this transmitter 1 is input to a transmitting circuit 2. The transmitting circuit 2 performs signal processing, modulation 1 frequency conversion, power amplification, etc. of the input audio signal, and converts the audio signal into high frequency power. This high frequency power is supplied to a transmitting/receiving antenna 4 via a transmitting/receiving splitter 3, and is sent out as radio waves.

On the other hand, high-frequency power obtained by receiving radio waves with the transmitting/receiving antenna 4 is split by the transmitting/receiving splitter 3 and input to the receiving circuit 5. The receiving circuit 5 performs processing such as frequency conversion, power amplification, and demodulation on the input high-frequency power, and reproduces the audio signal S1. After the reproduced audio signal S is subjected to signal processing, it is supplied to the PCM encoder 6. The PCM encoder 6 PCM-encodes the audio signal S1 according to the time slot signal generated by the time slot assigner 7, and generates audio data S3. The audio data S obtained by the PCM encoder 6 is temporarily stored in the audio data memory 9 via the control section 8. The audio data S'' stored in the audio data memory 9 is read out after a predetermined time delay and input to the PCM decoder 10. Then, the audio data S3 is decoded by the PCM decoder 10 according to the time slot signal generated by the time slot assigner 7 and reproduced into a small sound signal S, which is amplified by the amplifier 11 and then sent to the receiver 12. The voice is output from the handset 12 of the lever.

The audio signal S1 outputted from the receiving circuit 5 is also manually input to the modem 13, and is demodulated in this modem 13 for reproducing control data, and the signal S2 obtained here is manually input to the control section 8. be done. Historically, the modem 13 modulates the control data output from the control unit 8 and converts it into a control signal.
It is given to the transmitting circuit 2. The transmitting circuit 2 superimposes the signal a+r= input from the modem 13 on the audio signal.

Further, a human power section 14 is connected to the control section 8 so that an operator can give instructions to the control section 8 .

By the way, the control unit 8 has, for example, a microcomputer as a main control circuit, and has control data detection means 8a and signal replacement means 8b in addition to well-known general control means for cordless telephone devices. . Here, the control data detection means 8a detects control data from the signal S4 inputted from the modem 13, and functions as a control signal detection means. The signal part corresponding to the control data detected by the control data detecting means 8a in the sound data S stored in the memory 9 is replaced with a silent level signal.

The above is the configuration of the slave device. In addition, in the figure, 20 is a base unit with a well-known configuration, 21 is a transmitting/receiving antenna for the base unit, and 2
2 is a telephone line.

Then, the voice signal transmitted as a radio wave from the transmitting/receiving antenna 4 of the handset is received by the base unit 20 and transmitted to the telephone line 22. Furthermore, the audio signal transmitted via the telephone line 20 is sent out as a radio wave from the transmitting/receiving antenna 21 and transmitted to the handset.

Furthermore, control data (control signals) are exchanged between the slave unit and the base unit 20, superimposed on the audio signal.

Next, the operation of the cordless telephone device constructed as described above will be explained with reference to the operation time chart 1 shown in FIG.

First, the audio signal S1 transmitted via the upper line 22 and the base unit 20 and received by the receiving circuit 5 via the transmitting/receiving antenna 4 and the transmitting/receiving splitter 3 is converted into audio data S3 by the PCM encoder 6. It is converted and stored in the audio data memory 9.

In parallel with this, the audio signal S1 output from the receiving circuit
is demodulated by the modem 13 and inputted into the control section 8 as a signal S2. Here, the modem 13 sends the audio signal S
When demodulating , the control signal (
The control data portion becomes a digital signal in a predetermined format as shown in FIG. In the control section 8, the control data in this human power signal S2 is detected by the control data detection means 8a.

On the other hand, the signal replacement means 8b of the control section 8, while the control data is not detected by the control data detection means 8a,
The audio data S stored in the audio data memory 9 is sequentially read out after a predetermined time delay from its writing and is provided to the PCM decoder 10. That is, the data of the portion of the audio data S3 that is determined not to be the control signal portion is sequentially provided to the PCM decoder 1o. here,
The timing of reading audio data, that is, the delay time from the time of writing, is greater than or equal to Tsec, assuming that the maximum value of the control signal is Tsec.

In this way, the original audio data is sequentially applied to the PCM encoder 1o, decoded, and output as audio from the receiver 12.

By the way, when the control data is detected by the control data detection means 8a, the signal replacement means 8b converts the part corresponding to the control data in the audio data S3 stored in the audio data memory 9 into silence level data, that is, For example, after replacing the data with rOJ data, it is read out from the audio data memory 9 and applied to the PCM decoder 10. Therefore, the data read from the audio data memory 9 and applied to the PCM decoder 10 is as shown at 84 in FIG. By decoding this data s4,
An audio signal shown at 85 in FIG. 2 in which the control signal portion is at the "0" level (silence level) is obtained, and no control sound is output from the receiver 12.

Note that here, a silent level signal is used as the signal to replace the control signal part, but by using a signal that imitates natural noise as the signal to replace the control signal part, it is possible to reduce the noise caused by sudden silence. Naturalness can be removed.

As described in detail above, in this cordless telephone device, the control signal part in the audio signal sent from the base unit 20 is replaced with a signal at a silent level or a signal imitating natural noise, so that it is output from the receiver 12. Control sounds are not mixed in with the audio.

Note that the present invention is not limited to the above embodiments.

For example, in the above embodiments, the control signal detection means and the signal replacement means are provided on the handset side, or are provided on the base unit so that the control signal output from the handset to the base unit is transmitted as an audio signal to the telephone line. It can be prevented from being sent out.

Furthermore, by providing a control signal detection means and a signal replacement means in both the base unit and the handset, it is possible to eliminate both the control sound generated by the own handset and the control sound generated by the receiver/tongue of the communication partner terminal. It's a good idea to get the effect. In addition, when the control signal detection means and the signal replacement means are provided in the base unit, the transmitter 1 and receiver 12 of the slave unit shown in FIG. 1 can be replaced with a hybrid circuit! This can be achieved by changing.

Further, in the above embodiment, the control signal is removed by replacing the signal with digital processing, but the control signal may be removed by replacing the signal with an analog switch operation, etc. The signal is almost r
The control signal may be removed by attenuating it to an OJ level. Further, when a signal is replaced by digital processing, the signal used for the replacement is not limited to a silent level signal or a signal imitating natural noise, but may be any signal such as a hold tone.

Further, in the above embodiments, the wireless telephone device according to the present invention is applied to a cordless telephone device, but it can also be applied to other wireless telephone devices such as a car phone.

In addition, various modifications can be made without departing from the gist of the present invention.

[Effects of the Invention] According to the present invention, since the control signal in the audio signal is detected and the control signal El is removed from the audio signal by replacement, attenuation, etc., the control signal is transmitted in the audio band. This prevents complicating the device by
In addition, the control sound can be prevented from being mixed into the output voice, resulting in a wireless telephone device that does not cause discomfort to the user.

[Brief explanation of drawings]

The figures are diagrams for explaining a wireless telephone device according to an embodiment of the present invention, FIG. 1 is a block diagram showing the configuration of a cordless telephone device constructed by applying the same wireless telephone device, and FIG. 1 is an operation time chart of the cordless telephone device shown in FIG. DESCRIPTION OF SYMBOLS 1... Transmitter, 2... Transmitting circuit, 3... Transmitting/receiving duplexer, 4... Transmitting/receiving antenna, 5... Receiving circuit, 6...
... PCM encoder, 7... Time slot assigner, 8... Control section, 8a... Control data detection means, 8
b... Signal replacement means, 9... Audio data memory,
10...P CM Tecotor, 11... Amplifier, 1
2... Excellent device, 13... Modem, 14... Input section.

Claims (6)

[Claims] (1) In a radio telephone device applied to a radio telephone system that superimposes a control signal on a voice signal and transmits the same, the control signal detection means detects a control signal superimposed on a received signal; 1. A radio telephone apparatus comprising signal replacement means for replacing a portion of the received voice signal corresponding to the control signal detected by the means with a predetermined signal. (2) The radiotelephone device according to claim (1), wherein the predetermined signal to be replaced in the part corresponding to the control signal in the received audio signal is a silent level signal. (3) The radio telephone device according to claim (1), wherein the predetermined signal to be replaced in the portion corresponding to the control signal in the received voice signal is a natural noise signal. (4) In a radio telephone device applied to a radio telephone system that superimposes a control signal on a voice signal and transmits the same, the control signal detecting means detects the control signal superimposed on the received voice signal, and the control signal 1. A radio telephone apparatus comprising: signal attenuation means for attenuating a portion of the received voice signal corresponding to the control signal detected by the detection means. (5) In a radio telephone device comprising a fixed device and a mobile device, and in which control signals are transmitted and received between the fixed device and the mobile device by superimposing them on voice signals, the control signals are superimposed on the received voice signals. control signal detecting means for detecting a control signal detected by the control signal detecting means; and signal replacing means for replacing a portion of the received audio signal corresponding to the control signal detected by the control signal detecting means with a predetermined signal. A wireless telephone device characterized by being equipped with both. (6) In a radiotelephone device comprising a fixed device and a mobile device, and in which control signals are transmitted and received between the fixed device and the mobile device by superimposing them on voice signals, the control signals are superimposed on the received voice signals. and a signal attenuation means for attenuating a portion of the received audio signal corresponding to the control signal detected by the control signal detection means, both of the fixed device and the mobile device. A wireless telephone device characterized by: