JPH1070769A - Digital cordless telephone device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the digital cordless telephone device which can efficiently utilize a frequency band by making adjacent transmit and receive slots close in timing. SOLUTION: Two signals which are a clock signal and a slot timing signal are connected in series between master devices 1 and synchronized on the basis of the slot timing of one of the master devices 1. Each master device 1 outputs the slot timing signal with a delay of one time slot to prevent time slots in use from overlapping. Consequently, adjacent sent and receive slots are put close in timing to actualize the digital cordless telephone device which can efficiently utilize the frequency band.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital cordless telephone device for simultaneously performing communication between a plurality of master units and slave units on the same communication frequency channel.

[0002]

2. Description of the Related Art A cordless telephone device connects a base station called a base unit to a telephone line terminal of a general public line, a dedicated line, or an indoor line, and uses a weak radio wave with the base station. A device that communicates with a portable mobile communication terminal called a slave unit.

[0003] This cordless telephone device also protects privacy, makes effective use of frequency channels, or uses PHS.
(Personal Handy-phone System) terminals and PDC (P
In consideration of compatibility and commonality with personal digital (cellular) terminals, digital transmission types are increasing.

[0004] As described above, the cordless telephone apparatus communicates by radio waves, and several channels for communication are determined within a specific frequency band. Further, in order to use a limited channel in a plurality of cordless telephone devices, each channel is divided into a plurality of time slots on a time axis, and time-division information transmission for communicating between different cordless telephone devices in each time slot is used. Have been.

For example, Japanese Patent Laid-Open Publication No. Hei 4-286431 discloses a digital cordless telephone device which first detects the timing of transmission and reception by another nearby digital cordless telephone device. .

Next, a time slot that does not interfere with the detected transmission / reception timing is calculated, and transmission and reception are performed between the parent device and the child device at the position of the calculated time slot.

Japanese Patent Laid-Open Publication No. Hei 8-19041 discloses a communication method between slave units. According to the method disclosed in this publication, a slave unit of a digital cordless telephone device is controlled by a surrounding master unit. By transmitting and receiving a control signal and a response signal to the control signal at a timing synchronized with a signal transmitted using a channel, synchronization between slave units is achieved.

[0008]

However, in the above-described configuration and method, a plurality of digital cordless telephone devices operate asynchronously. Therefore, each cordless telephone device must monitor the call timing of another cordless telephone device at regular time intervals and correct its own call timing before interference occurs, which complicates the circuit configuration.

In these digital cordless telephone devices, TDMA (Time Division Multiple) is used.
Access: Time Division Multiple Access / TDD (Time Division)
If one frame is composed of four time slots for transmission and reception, for example, time-divided using the Duplex (time-division bidirectional transmission) method, it is possible to multiplex up to four calls on the same channel. become.

However, in the conventional digital cordless telephone device, it is necessary to prevent the time slot being used by another digital cordless telephone device from overlapping.

For this reason, it is necessary to allow time slots to be arranged by providing a guard slot between two adjacent time slots or setting an empty slot for one slot. Therefore, actually 3
There was a problem that only the telephone call could be used and the frequency utilization efficiency was low.

The present invention has been made under such a background, and has as its object to provide a digital cordless telephone apparatus in which the timings of adjacent transmission / reception slots are made close to each other and a frequency band can be used efficiently.

[0013]

Means for Solving the Problems In order to solve the above-mentioned problems, the invention according to claim 1 comprises a plurality of master units and a plurality of slave units paired with the master units. A digital cordless telephone device in which a combination of a master unit and a slave unit simultaneously uses the same frequency channel, wherein each of the master units includes first input means for inputting a clock signal output from an external device, and a clock signal. Clock signal generating means for generating a slot timing signal output from an external device, a second input means for generating a slot timing signal, and a slot timing signal generating means for generating a slot timing signal; Transmitting / receiving means for transmitting / receiving a radio wave based on any of the input clock signal and the generated clock signal A control means for controlling the transmitting and receiving means based on the supplied clock signal and the supplied slot timing signal, wherein one of the input slot timing signal and the generated slot timing signal is supplied; First output means for outputting the clock signal supplied to the control means to an external device, and one of the input slot timing signal and the generated slot timing signal supplied, and supplied slot timing It is characterized by comprising delay means for delaying a signal by one slot, and second output means for outputting a slot timing signal output by the delay means to an external device. According to the second aspect of the present invention, in the digital cordless telephone according to the first aspect, the first, second, third,... , The second, the third,..., The (n−1) -th, n-th master unit, and the slave unit paired with the master unit. A clock signal to be generated and a slot timing signal generated by the slot timing generation means are supplied, and the delay means of the first master unit is supplied with a slot timing signal generated by the slot timing generation means, The first output means and the second output means of the first master unit are connected to the first input means or the second input means of the second master unit, respectively. Before the second and subsequent master units A clock signal input to the first input means and a slot timing signal input to the second input means are supplied to the control means, and the delay means included in the second and subsequent master units is provided with the delay means The slot timing signal input to the second input means is supplied, and the first output means and the second output means of the second master unit are respectively provided to the first output means and the second output means of the third master unit. The first input means or the second input means is connected to the first input device of the (n-1) th base unit.
The output means and the second output means are connected to the first input means or the second input means of the n-th master unit, respectively.

According to the present invention, two signals of a clock signal and a slot timing signal are connected in series between a plurality of master units, and synchronization is established based on one slot timing among the plurality of master units. . Each of these base units delays the slot timing signal by one time slot and outputs the signal, so that the time slots to be used are not duplicated.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION

A. Configuration The present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a base unit 1 of a digital cordless telephone device according to one embodiment of the present invention. FIG. 1
Here, only one master unit 1 is shown.

In FIG. 1, reference numeral 2 denotes a clock input terminal to which a clock signal supplied from an external device is input.
It is connected to a control unit 5 described later. A slot timing input terminal 3 receives a slot timing signal supplied from an external device, and is connected to a slot timing generator 6 described later.

Reference numeral 4 denotes a clock generator for generating a clock signal in the master unit 1. The clock signal generated by the clock generator 4 is connected to the controller 5. When a slot timing signal is not supplied to the slot timing input terminal 3, the slot timing generator 6 generates a slot timing signal by itself and supplies it to the controller 5.

Reference numeral 7 denotes a radio unit for communicating with the slave unit via the antenna 11, and the control unit 5 controls transmission and reception based on the supplied clock signal and slot timing signal.

Reference numeral 8 denotes a shift register which shifts (delays) the slot timing signal supplied from the slot timing generator 6 by one slot and outputs the shifted signal from the slot timing output terminal 10.

Reference numeral 9 denotes a clock output terminal. A clock signal supplied to the control unit 5 from the clock input terminal 2 or from the clock generation unit 4 is output from the clock output terminal 9 to an external device.

B-1. First Operation Here, a case will be described in which a clock signal or a slot timing signal is not supplied to the clock input terminal 2 and the slot timing input terminal 3 of the base unit 1, respectively.

In this case, the control unit 5 includes the clock generation unit 4
A clock signal or a slot timing signal is supplied from the slot timing generator 6. The control unit 5 performs signal processing based on the input clock signal, recognizes a position of a preset time slot based on the input slot timing signal, and transmits or transmits the time slot to the radio unit 7 using this time slot. Instruct reception.

The control section 5 outputs the input clock signal from a clock output terminal 9. The clock signal output from the clock output terminal 9 is supplied to a clock input signal of another master unit 1.

On the other hand, the slot timing generator 6 supplies a timing slot signal to the shift register 8. The shift register 8 delays the timing slot signal by one slot and outputs it from the time slot output terminal 10.

B-2. Second operation Figure 2 is a plurality of base unit 1 (each in 2 main unit 1 _-1, 1 _-2
... 1- _n , after that, if necessary, simply the master unit 1
FIG. 6 is a timing chart showing transmission and reception timings when a clock signal and a slot timing signal are connected in series at _-n .

In FIG. 2, the hatched portions indicate the time slots transmitted and received by the master units 1- _n , respectively.
The left sloping line indicates a transmission slot, and the right sloping line indicates a reception slot.

In this operation example, the clock output terminal 9 of each master unit 1 _-n (for example, 1 _-1 ) is connected to the following master unit 1 _-n.
-n (for example, 1 _-2) is the clock input terminal 2 is connected, the slot timing output terminal 8 of the main unit 1 _-n parent machine 1 _-n slot timing input terminal 3 to follow connected.

[0028] However, the clock input terminal 2 and the slot timing input terminal 3 with the base unit 1 _-1, is not supplied each clock signal or the slot timing signal. Therefore, master unit _1-1 serves as a reference master unit that generates a clock signal and a slot timing signal by itself.

In the second operation example, each master unit 1- _n delays the supplied slot timing signal by one slot by the shift register 10, and supplies the delayed slot timing signal to the next following master unit 1- _n .

For this reason, the transmission slot timing and the reception slot timing of each parent device 1- _n are shifted by exactly one slot as shown in FIG. Therefore, even if adjacent time slots are used for each parent device 1- _n , they do not overlap with each other.

The present invention is applicable to not only digital cordless telephones but also PHSs and PDCs, digital mobile telephones, and wireless information terminal networks.

[0032]

As described above, according to the present invention, two signals of a clock signal and a slot timing signal are connected in series between a plurality of master units, and one of the plurality of master units is connected.
Synchronization is performed based on the slot timings of the units. Each of these base units delays the slot timing signal by one time slot and outputs the time slot, so that the time slots to be used are not overlapped. An effect that a cordless telephone device can be realized is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a base unit 1 of a digital cordless telephone device according to one embodiment of the present invention.

FIG. 2 is a timing chart showing transmission and reception timings when a plurality of master units 1 are connected in series in the embodiment.

[Explanation of symbols]

1 base unit 1 _-1, 1 _-2 ... 1 _-n base unit (first, second, third..
(N-1st, n-th master) 2 clock input terminal (first input means) 3 slot timing input terminal (second input means) 4 clock generator (clock signal generator) 5 controller (controller) 6) Slot timing generator (slot timing signal generator) 7 Radio unit (transmitter / receiver) 8 Shift register (delay unit) 9 Clock output terminal (first output unit) 10 Slot timing generator (second output unit)

Claims (2)

[Claims] A digital cordless telephone device comprising a plurality of base units (1) and a plurality of slave units paired with the base unit, wherein a combination of the plurality of base units and the slave units simultaneously uses the same frequency channel. Each of the base units includes first input means (2) for inputting a clock signal output from an external device, and clock signal generating means (4) for generating a clock signal.
Second input means (3) for inputting a slot timing signal output from an external device; slot timing signal generating means (6) for generating a slot timing signal; Transmitting / receiving means (7) for transmitting / receiving a radio wave by using any one of the input clock signal and the generated clock signal, and receiving the input slot timing signal and the generated slot timing signal Control means (5) for controlling the transmission / reception means based on the supplied clock signal and the supplied slot timing signal; and transmitting the clock signal supplied to the control means to an external device. First output means (9) for outputting, the input slot timing signal and the generation Delay means (8) for delaying the supplied slot timing signal by one slot, and a second output means for outputting the slot timing signal output by the delay means to an external device. (10) A digital cordless telephone device comprising: 2. The first, second, third,..., N-1 and n-th
_.. , 1 _{- n} ) and the first, second, third,..., N−1, and n-th base units. A clock signal generated by the clock signal generation means and a slot timing signal generated by the slot timing generation means are supplied to the control means of the first parent device; The slot timing signal generated by the slot timing generation means is supplied to the delay means included in the first master unit. The first output means and the second output means of the first master unit are respectively provided with a second timing signal. The first input means or the second input means of the master unit is connected, and the control means of the second and subsequent master units is connected to the first input means.
The clock signal input to the input means and the slot timing signal input to the second input means are supplied, and the delay means included in the second and subsequent master units is provided with the second
A slot timing signal input to the input means is supplied, and the first output means and the second output means of the second master unit are provided with the first timing of the third master unit, respectively. The input means or the second input means is connected to the first output means and the second output means of the (n-1) th master unit. 2. The digital cordless telephone device according to claim 1, wherein the first input means or the second input means is connected.