JPS645791B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radio telephone that connects a handset equipped with a dial switch and a base set via a cord, and particularly relates to a radio telephone that is capable of reducing the number of core wires of the cord. Related to dial signal transmission method.

2. Description of the Related Art In recent years, some wireless telephone devices have a dial switch built into the handset so that dialing operations can be performed at hand, and are also equipped with a switch corresponding to a touch switch. FIG. 1 shows an example of the configuration of this type of telephone.

In the figure, this telephone transmits contact signals outputted from a switch 11 corresponding to a switch 11 of a handset 1 and a dial switch 12 (3x4 matrix configuration) in parallel via a cord 2 to a control circuit of a base set 3. It leads to 31. After the control circuit 31 converts each contact signal into, for example, a digital code signal, the transmitter 32 modulates a carrier wave with this code signal, and the modulated wave is transmitted from an antenna 33 via a wireless line 4 (not shown). It is being sent to the base station. The base station regenerates a digital code signal from the modulated wave, generates, for example, a two-wave parallel dial tone signal and sends it to the subscriber line in accordance with the corrected signal.
Further, the telephone receives a modulated signal from the base station via the antenna 34 of the base set 3 at the receiver 35, reproduces the audio signal, and transmits the audio signal to the code 2.
to the handset 13 of the handset 1 via the
It is outputting. On the other hand, the audio signal from the transmitter 14 is sent via the code 2 to the transmitter 32 of the base set 3, modulated by the transmitter 32, and sent from the antenna 33 via the radio circuit 4 to the base station. .

Therefore, in order to connect between the handset 1 and the base set 3, a telephone with such a configuration has seven wires for transmitting contact signals of the dial switch 12, and seven wires for transmitting contact signals of the switch 11, which corresponds to a hook switch. one for the transmitter 14 and the other for the receiver 13, each consisting of a signal wire and a ground wire.
A total of 12 core wires are required for the book.

For this reason, the above-mentioned conventional telephones have had the following various drawbacks.

(i) Since the number of core wires in the cord 2 increases to 12, the cord 2 becomes thick and the operability of the handset 1 deteriorates. In particular, generally the above code 2
Since the base set 3 is formed of a curled cord, the spring force of the cord increases, and when the handset 1 is operated, the base set 3 is pulled by the cord 2 and may move, possibly causing the base set 3 to fall.

(ii) The thickening of the cord 2 is a major hindrance in making the telephone more compact, and is also unfavorable in terms of appearance.

(iii) In order to eliminate each of the above-mentioned drawbacks, the diameter of each core wire can be made thinner, but making it thinner not only increases the risk of wire breakage, but also increases impedance, making it easier to pick up noise. Particularly in the case of curled cords, signal interference is likely to occur between core wires, resulting in a significant drop in S/N.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to improve the operability of the handset by reducing the number of core wires in the cord, contribute to the miniaturization of the telephone, and to reduce the number of core wires in the cord.
An object of the present invention is to provide a dial signal transmission system for a radio telephone that does not cause a drop in N, consumes little power, and can extend the life of a battery.

The present invention detects the operation of a dial switch (including this switch if a switch equivalent to a box switch is on the handset side), sends a signal to that effect to the base set, and when this signal arrives, a clock pulse signal is generated. The contact signal of the dial switch is at least parallel-serial converted in synchronization with the clock pulse signal and sent to the base set, and furthermore, switching means is provided in the supply path of the power output from the base set to the handset. This switching means is made conductive to supply power output only when the dial switch is operated, thereby achieving the above object.

An embodiment of the present invention will be described below with reference to FIG. In FIG. 2, the same parts as those in FIG. 1 are given the same reference numerals and detailed explanations will be omitted.

FIG. 2 is a circuit block diagram of a radio telephone to which the dial signal transmission system of this embodiment is applied, in which a handset 10b is connected to a base set 30b via a cord 20a. The handset 10b includes a switch (hereinafter abbreviated as a switch) 1 corresponding to the above-mentioned switch.
1. In addition to the dial switch 12, the receiver 13, and the transmitter 14, a timing circuit 15a, a parallel-to-serial conversion circuit (P/S) 16a, and an encoding circuit 17
and a switching circuit 18 for power supply control consisting of a transistor.

The timing circuit 15a detects the generation of each contact signal of the switch 11 and the dial switch 12, and when it detects this, supplies a signal to that effect to the parallel-to-serial conversion circuit 16a, and also outputs the code 20a.
The signal is then sent to the control circuit 36a of the base set 30b. This timing circuit 15a
is constituted by, for example, an OR circuit that receives each contact signal as input. Also, parallel-to-serial conversion circuit 1
Reference numeral 6a converts each contact signal from a parallel format to a serial format in synchronization with a clock pulse signal sent from a control circuit 36a of a base set 30b, which will be described later, and sends it to the base set 30b. It consists of an 8-bit shift register circuit with parallel inputs. Further, the encoding circuit 17 encodes each contact signal of the dial switch 12 and the switch 11 into a 4-bit digital code signal, and converts this digital code signal into a serial format by the parallel-to-serial conversion circuit 16a to control the base set 30b. It is sent to the circuit 36a.

The switching circuit 18 is controlled on and off by the common contact 12a of the dial switch 12 and the switch 11, and is turned on only when these switches are operated, supplying power output to each circuit of the handset 10b. have them do it.

On the other hand, the base set 30b has a control circuit 36a having a different configuration instead of the control circuit 31 described in FIG. This control circuit 36a is
In addition to controlling the operations of the transmitter 32 and receiver 35, it also performs the following control operations. That is, (i) the timing circuit 1 of the handset 10b;
When a signal indicating that the contacts of switches 11 and 12 have been operated is received from 5a,
Control for sending the clock pulse signal to the parallel-to-serial conversion circuit 16a via the code 20a.

(ii) Control for inputting the serial contact signal sent out from the parallel-to-serial conversion circuit 16a, encoding this signal and converting it into, for example, a dial code signal, and then sending it out from the transmitter 32 to the radio circuit 4. Note that when the transmission of the dial code signal is finished, the operation of transmitting the clock pulse signal is also stopped.

Further, the base set 30b is provided with a power supply circuit, and its output V is supplied to the handset 10b after passing through the cord 20a, and within this handset 10b, it is connected to the timing circuit 15a and the parallel/serial conversion circuit via the switching circuit 18. 16a and an encoding circuit 17.

Note that the signal line for the handset 13 includes the handset 1.
Stopping capacitors 19a and 37a are provided on the 3 side and the receiver 35 side, respectively, and a low pass filter (LPF) 19b consisting of a capacitor and a resistor.
37b. This LPF19b,3
7b is for preventing the output of the receiver 35 from entering the power supply path of the power supply circuit, the encoding circuit 17, etc.

With such a configuration, for example, when dial switch 12 is operated when making a call, and a contact signal is generated according to the operating position, this signal is generated by timing circuit 15a via encoding circuit 17. It is detected, and a signal to that effect is sent to the control circuit 36a of the base set 30. For this purpose, a clock pulse signal is sent from the control circuit 36a to the parallel-to-serial conversion circuit 16a of the handset 10b, and as a result, each contact signal of the dial switch 12 encoded by the encoding circuit 17 is parallelized in synchronization with this clock pulse signal. The serial conversion circuit 16a converts the parallel format into a serial format and sends it to the control circuit 36a. At this time, the contact signal of the switch 11 is also sent out in the same way following each of the above contact signals. Therefore, the form of the signal sent from the parallel-to-serial conversion circuit 16a to the control circuit 36a is such that the encoding circuit 17 converts the 7 bits of the dial switch 12 and the 1 bit of the switch 11 into a total of 8 bits of parallel signals. For example, it is a serial signal string converted into 4 bits. When the transmission of each contact signal is completed, the control circuit 36a causes the transmitter 32 to transmit the transmitted encoded signal to the base station via the wireless line 4. For this reason, as is well known hereinafter, a dial tone or dial pulse is sent from the base station to the exchange, and if the called party responds to this call, the telephone becomes in a talking state.

On the other hand, for example, if the switch 11 is closed during this call, a contact signal to that effect is generated as in the case of the dial switch 12, and this is detected by the timing circuit 15a, which causes a clock pulse signal to be sent from the control circuit 36a. is generated.
Then, in synchronization with this clock pulse signal, the contact signal of the switch 11 is converted into a 4-bit encoded signal and sent out from the parallel-to-serial conversion circuit 16a. A similar well-known operation is used to complete the call termination process. It should be noted that all judgments such as whether or not the contact signal corresponds to the switch 11 are made by the control circuit 36a.

In this way, in this embodiment, the switch 1 corresponding to the dial switch 12 and the hook switch is
Each contact signal generated by 1 is converted from a parallel format to a serial format and sent to the base set 30b, and power is supplied from the base set 30b to the handset 10b using the core wire for the receiver 13. Therefore, the number of core wires of the cord 20a is: - For sending the above contact signal - 1 - For sending the signal from the timing circuit 15a to the control circuit 36a - 1 - For sending the clock pulse signal from the control circuit 36a - 1 For handsets 13 and 14 - a total of 4 can be reduced to 7, which can be reduced to less than 2/3 compared to the conventional 12. Therefore, since the cord 20a can be made small in diameter, even if it is a curled cord, problems such as the base set 30b easily moving as the handset 10b moves will not occur, and it will also be possible to make the telephone more compact. It does not become an obstacle. Furthermore,
Since the cord 20a can be made small in diameter, there is no need to make the diameter of the core wire small, and as a result, wire breakage, noise mixing, interference, etc. can be made less likely to occur.

Furthermore, according to this embodiment, the contact signal is parallel-serial converted and sent out in synchronization with the clock pulse signal sent from the control circuit 36a, so a stable signal can be generated without providing a particular oscillation source on the handset 10b side. A sending operation can be performed. Moreover, since the clock pulse signal is transmitted only when the timing circuit 15a detects the occurrence of a contact signal, the clock pulse signal is not transmitted during a call, and as a result, the clock pulse signal is transmitted at the code 20a. The S/N of the call leaked to the line for receivers 13 and 14.
It does not cause any inconveniences such as those caused by deterioration.

Furthermore, in this embodiment, the contact signal is encoded by the encoding circuit 1.
Since the data is transmitted after being converted to a 4-bit signal in step 7, the transmission time can be reduced compared to, for example, transmitting a contact signal in an 8-bit state, and this makes it easier to send dial signals. The time required can be shortened. Further, the timing circuit 15a only needs to OR the 4-bit digital code signal, and the parallel-to-serial conversion circuit 1
6a also needs to use a 4-bit shift register circuit, so the circuit configuration can be simplified.

Further, the digital code signal is transmitted to the control circuit 36.
When introduced in (a), the transmitter 32 can directly transmit data to the base station without any conversion operation, so it not only achieves the above-mentioned effects, but also simplifies the configuration of the control circuit. do.

Further, in this embodiment, a switching circuit 18 is provided in the power supply path in the handset 10b, and the switching circuit 18 supplies power to the encoding circuit 17 and the like only when the dial switch 12 and the switch 11 are operated. As a result, power consumption can be significantly reduced compared to the case where the power is constantly supplied. This effect is extremely effective in the case of equipment that uses a battery such as a battery as a power source, such as a radio telephone to which the present invention is directed, since it can greatly extend the life of the battery.

Note that the present invention is not limited to the above embodiments. For example, in the above embodiment, the contact signal is encoded and transmitted, but it does not necessarily have to be encoded, and the power supply path from the base set to the handset can be routed through a single core wire instead of using a telephone core wire. may also be used. In addition, various modifications may be made to the structure of the contact signal sending means, operation detecting means, clock sending means, power supply means, power supply path switching means, etc. without departing from the gist of the present invention.

As detailed above, the present invention detects at least the operation of a dial switch, sends a signal to that effect to the base set, and upon arrival of this signal, sends a clock pulse signal to the handset, and synchronizes with this clock pulse signal. The contact signal of the dial switch is at least parallel-serial converted and sent to the base set, and a switching means is provided in the power supply path from the base set to the handset, and the switching means supplies power only when the dial switch is operated. It was designed to do this.

Therefore, according to the present invention, it is possible to improve the operability of the handset by reducing the number of core wires in the cord, contribute to the miniaturization of the telephone, and improve the S/N of the call.
It is possible to provide a dial signal transmission method for a radio telephone that does not reduce power consumption, reduces power consumption, and extends battery life.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a telephone set using a conventional contact signal transmission system, and FIG. 2 is a block diagram of a radio telephone set using a dial signal transmission system according to an embodiment of the present invention. 10b...handset, 20a...cord,
30b...Base set, 11...Switch, 1
2...Dial switch, 15a...Timing circuit, 16a...Parallel-serial conversion circuit, 17...Encoding circuit, 18...Switching circuit, 19a, 3
7a...Stopping capacitor, 19a, 37
b...Low pass filter, 36a...Control circuit,
V... Output of power supply circuit.

Claims (1)

[Scope of Claims] 1. In a dial signal transmission system of a radio telephone in which a handset having at least a dial switch as a switch and a base set are connected by a curl cord containing a plurality of core wires, the dial switch is operated. a dial operation detection means for detecting this every time the dial switch is turned on and sending a signal to that effect to the base set via the one-core wire of the curl cord; clock sending means for sending a fixed number of clock pulse signals to the handset via the one-core wire of the curl cord; and each time the dial switch is operated, a contact signal corresponding to the operated switch is temporarily stored. contact signal sending means for converting the contact signal from at least a parallel signal format to a serial signal format, reading out the converted signal, and sending the read signal to the base set via the one-core wire of the curl cord in synchronization with the clock pulse signal sent from the clock sending means; , a means for generating dial information in a predetermined format according to the contact signal sent from the contact signal sending means, and a power output for driving at least the dial operation detecting means and the contact signal sending means. A power supply means that uses a core wire to supply power from the base set to the handset; and a power supply means that is inserted into the power supply path of the power supply means and conducts only when the dial switch is operated to supply the power output to the handset side. What is claimed is: 1. A dial signal transmission system for a radio telephone, characterized in that it is equipped with a switching means for transmitting a dial signal. 2. Claims characterized in that the power supply means supplies power output from the base set to the handset using the core wires of the curl cord for transmitting audio signals to the handset of the handset. 2. A dial signal transmission method for the wireless telephone set forth in item 1.