JPH03150959A - Radio telephony equipment - Google Patents

Abstract

PURPOSE:To prevent production of sound giving a sense of displeasure to the user by using a frequency other than audible frequency so as to apply FSK modulation to a header part of a data. CONSTITUTION:A control circuit 2 at a sender side gives a control signal to an FSK modulation circuit 3 while a header part of a data is outputted at data communication between a master set and a slave set to bring the modulation frequency to a frequency at the outside of audible frequency band. When the header part is included in an output signal from a detection circuit 10 at a receiver side, the header part is FSK-demodulated and fed to the control circuit 12, the control circuit 12 discriminates the data reception state based on the demodulated signal and outputs a muting control signal to a muting circuit 13 to activate the muting. Thus, an unpleasant sound generated in a conventional telephone set at data reception is surely prevented.

Description

[Detailed description of the invention] (b) Industrial application field TECHNICAL FIELD The present invention relates to radiotelephone equipment.

(B) Prior Art Conventionally, a wireless telephone device is known which includes a base unit connected to a telephone line and a slave unit connected to the base unit via a wireless line.

In this type of conventional wireless telephone device, a control circuit consisting of a microcomputer outputs digital data in response to a key signal input from a key power section, and this digital data is modulated into an FSX signal by a modulation circuit (modem). . and,
The transmission carrier wave is modulated with this FSK signal.

On the other hand, on the receiving side, the received FSK signal is demodulated into a digital signal by a modem, and this digital signal is supplied to a control circuit consisting of a microcomputer.

Thereafter, the control circuit performs control according to the digital signal.

(C) Problems to be Solved by the Invention In the conventional radio telephone device described above, frequencies in the audible frequency band are used for the marks and spaces of the FSX signal due to reasons such as transmission speed and radio bandwidth. Further, during data transmission, a muting circuit is provided to mute frequencies unrelated to telephone calls, and the muting circuit is operated when the control circuit detects that the signal is a data signal.

However, until the control circuit determines whether the received signal is a data signal or an audio signal, the FS
There is a problem in that the X signal is supplied to the amplifier and an undesired signal is emitted.

(d) Means for Solving the Problems In view of the above problems, the present invention provides a wireless telephone device comprising a base unit connected to a telephone line and a slave unit connected to the base unit via a wireless line. At the time of data communication between the base unit and the slave unit, a modulation circuit for FSK modulating the header part of the data using a frequency other than an audio frequency is provided on the transmitting side, and the modulation circuit is provided on the receiving side. The present invention is characterized in that it is provided with a control circuit that determines the presence or absence of data based on the modulated output of the transmitter, and operates muting when determining data reception.

(E) Effect According to the present invention, since the data header part is FSK modulated using a frequency other than the audio frequency, the FS
Undesired signals are not generated based on the X signal (data). Additionally, while the control circuit determines whether the received signal is data or voice, the FSK signal is supplied to the amplifier;
Even if the signal is amplified, it will not cause discomfort to the user since it is outside the audible frequency band.

(F) Embodiment FIG. 1(A) is a diagram showing a transmitting system of a radio telephone device according to the present invention, and FIG. 1(B) is a diagram showing a receiving system.

In the figure, (1) is a key power unit having a call key, a numeric keypad, etc., and (2) is a microcomputer, which generates digital signals corresponding to key signals in response to key signals from the key power unit (1). Output control circuit, (3)
(4) is an FSX modulation circuit that performs FSX modulation of the digital signal supplied from the control circuit (2) based on the frequency determined by the control signal from the control circuit (2);
This is a transmission carrier wave oscillation circuit whose oscillation frequency is controlled based on the control signal from 2), and is configured with a phase locked loop (PLL). (5) is a modulation circuit that modulates the oscillation signal from the transmission carrier wave oscillation circuit (4) with the FSX signal from the FSK modulation circuit (3), and (6) is a modulation circuit that modulates the oscillation signal from the transmission carrier wave oscillation circuit (4) with the FSX signal from the FSK modulation circuit (3). (7) is a transmitting antenna, (8) is a receiving antenna,
(9) is a receiving unit that receives the high frequency signal received by the receiving antenna (8) and converts it into a predetermined intermediate frequency signal;
(10) is a detection circuit that detects the intermediate frequency signal from the receiver (9), and (11) converts the detection signal from the detection circuit (lO) into a frequency determined based on the control signal from the control circuit (12). (12)
is a control circuit that determines whether the received signal is data or voice according to the demodulated signal from the FSK demodulation circuit (11),
It is composed of a microcomputer. (13) is connected to the output terminal of the detection circuit (10), and the control circuit (12) is connected to the output terminal of the detection circuit (10).
), the muting circuit (14) is controlled by the muter control signal (S) from the muting circuit (
13), and (15) is a /1 hybrid circuit placed between the amplifier circuit (14) and the telephone line (L), for example, a two-wire conversion circuit.

(16) is a speaker to which the signal amplified by the amplifier circuit (14) is supplied. Note that a hybrid circuit is not provided in the reception system of the handset.

Next, the operation will be explained.

Now, when you operate the key on the key human power section (1), the control circuit (
2) outputs a digital signal corresponding to this operated key. Such a digital signal is composed of a header section indicating the start of data and a data section indicating the data content, and the control circuit (2) controls the header section while the header section is being output.
A control signal is supplied to the FSK modulation circuit (3) to set the frequency for modulation to a frequency outside the audible frequency band. When the output of this header section is completed, the control circuit (2)
supplies a control signal to the FSX modulation circuit (3) to set the modulation frequency to an audible frequency.

The output signal from this FSK modulation circuit (3) is supplied as a modulation signal to the modulation circuit (5), and the transmission carrier wave oscillation circuit (
4) modulates the transmit carrier signal output from. This modulated transmission carrier wave is amplified to a predetermined transmission level in a transmission amplifier circuit (6) and then transmitted from a transmission antenna (7).

When this transmission signal is received by the reception antenna (8), it is converted to a predetermined intermediate frequency by the reception circuit (9), and then demodulated by the detection circuit (10). This detection circuit (1
The detected signal from FSK demodulation circuit (11) is supplied to the FSK demodulation circuit (11). At this time, the FSK demodulation circuit (11) is controlled by the control circuit (
FSK demodulation is performed at a frequency outside the audible frequency band using a control signal from the detection circuit (10).
If the header section is included in the output signal from the control circuit (12), the header section is FSK demodulated and supplied to the control circuit (12).

The control circuit (12) determines that it is in the data reception state based on this demodulated signal, and the muting circuit (12) determines that it is in the data reception state based on this demodulated signal.
13) outputs a muting control signal (S) to operate muting. At the same time, a timer (not shown)
The FSK demodulation circuit (11) is operated until the measured time t of this timer matches the transmission time T of the header section.
Let the frequency be a frequency outside the audible frequency band.

When the measured time t of the timer matches the transmission time T of the header section, the control circuit (12) sends a control signal to the FSK demodulation circuit (11) by fJ% in order to demodulate the data section.
and set to perform FSK demodulation at an audio frequency.

Then, the FSK demodulation circuit (11) demodulates the data part,
Supplied to the control circuit (12). The control circuit (12) performs various controls based on this data section.

Completion of reception of the data portion is determined, and when reception of the data portion is completed, muting is canceled by inverting the polarity of the muting control signal.

In this way, the operation of the present invention is achieved, but the present invention is not limited to the above embodiments, for example, a first FSKW modulation circuit for FSX demodulation at an audio frequency and an FSK demodulation circuit for FSX demodulation at a frequency outside the audio frequency band. A second FSK demodulation circuit for demodulation may be provided, and the muting circuit may be operated in response to a signal from the second demodulation circuit.

(G) Effects of the Invention According to the present invention, when communicating data between a base unit and a slave unit, a modulation circuit is provided on the transmitting side to perform FSX modulation on the header part of the data using a frequency other than an audio frequency. ,
A control circuit is installed on the receiving side to determine the presence or absence of data based on the modulation ratio power of the modulation circuit, and to operate muting when determining data reception, thereby eliminating the unpleasant noise that conventionally occurs when receiving data. It can be prevented.

[Brief explanation of the drawing]

FIG. 1(A) is a diagram showing the transmitting system of the wireless telephone device according to the present invention, FIG. 1(B) is a diagram showing the receiving system, and FIG. 2 is a diagram for explaining the operation of the receiving system of the present invention. It is a flowchart. (1)...Key human power section, (2)...Control circuit, (3
)...FSK modulation circuit, (4)...transmission carrier wave oscillation circuit, (5)...modulation circuit, (9)...reception circuit,
(10)...detection circuit, (11)...FSK demodulation circuit, (12)...control circuit, (13)...muting circuit.

Claims (1)

[Claims] (1) A wireless telephone device consisting of a base unit connected to a telephone line and a slave unit connected to the base unit via a wireless line, during data communication between the base unit and the slave unit. , a modulation circuit that performs FSK modulation of the header part of the data using a frequency other than an audio frequency is provided on the transmitting side, and the presence or absence of data is determined on the receiving side based on the modulation output of the modulation circuit, and when determining data reception. , a wireless telephone device comprising a control circuit for operating muting.