JP3500528B2 - Connection device for digital cordless telephone equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plurality of connecting devices connected to an extension bus from a main unit of a home telephone or a key telephone device, and these connecting devices and TDMA / TDD.
The present invention relates to a connection device in a digital cordless telephone device including a plurality of slaves connected by a wireless line using a system (time division multiple access time division bidirectional communication system).

[0002]

2. Description of the Related Art Conventionally, in a digital cordless telephone system, when a plurality of slaves are used at the same time, the following two methods are used. By controlling the frequency and controlling the transmission / reception slot by the control unit of the main device, centralized control is performed so as not to give interference in the wireless transmission path of each connection device. Alternatively, there is a method in which transmission / reception slots are asynchronously distributed between the connection devices.

[0003]

However, in the former centralized control method, the load on the control unit of the main device is large and complicated control means is required. Further, in the latter conventional distributed processing method, since radio wave interference occurs between the connection devices, considering the transmission / reception characteristics of the radio section against radio wave interference, the number of digital cordless telephone devices that can be accommodated is limited, and about three devices can be accommodated. It could only accommodate. An object of the present invention is to provide a connecting device which can increase the number of connecting devices in one digital cordless telephone device by the distributed processing method which solves the above-mentioned problems.

[0004]

The present invention has the following constitution in order to achieve the above object. (1) A plurality of connecting devices connected to an extension bus from a main device of a home telephone or a key telephone device, and a plurality of cordless handsets connected to these connecting devices by a wireless line using a TDMA / TDD system are provided. The digital cordless telephone device is provided with a multi-frame clock from the multi-frame signal of the downstream bus data sent from the main device through the extension bus, and means for generating a basic frame signal, and the reference clock generated by the basic frame signal. Generating means, means for receiving a reference clock of the reference clock generating means to generate a reference timing, and data for activating slot synchronization between connection devices which are inserted in a multi-frame signal of downlink bus data and which are transmitted at a constant cycle. After receiving, the reference timing is generated by the above multi-frame clock. The first connecting device arranges the transmission slot at the same time as the reference time point of the reference timing, and at the same time, the other connecting device delays from the reference time point by a sequentially positive integer multiple of the transmission / reception slot timing period. A connection device for a digital cordless telephone device that performs transmission / reception slot synchronization without phase shift between the connection devices by distributed processing on the connection device side. (2) When connecting more than the number of transmission / reception slots to the main device, the time from the reference time point of the reference timing to its own transmission slot so that the number of overlaps of the transmission / reception slots without phase shift is minimized. A connection device having the same width as other connection devices and using overlapping transmission / reception slots without phase shift is used for connection of the digital cordless telephone device according to the first item, in which carrier sensing is used to use different transmission frequencies. apparatus.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing a TDMA / TDD frame composed of transmission / reception slots according to an embodiment of the present invention, and FIG. 2 (1) is a basic frame × N pieces coming from a receiving line of an extension bus. FIG. 2 (2) is a diagram showing a multi-frame signal to be configured, FIG. 2 (2) is a diagram for extracting a multi-frame clock MFCK from the multi-frame signal, and FIG. 2 (3) is a diagram for extracting a basic frame signal from the multi-frame signal. .
FIG. 3 is a block diagram of a home telephone using the digital cordless telephone device of the present invention. FIG. 4 is a block diagram of the connection device. 1 is a main device, 2 is a connection device (CS1 to CS1
L), 3 is an antenna, and 4 is a slave unit (PS). 10 is a central office switch, 11 is an ISDN line or a telephone line, 12
Is an extension bus, 14 is a telephone connected to the extension bus, 20
Is a digital cordless telephone device including a part of the main device 1, a connection device 2 and a group of slave units 4. 21 is an extension bus connector, 23 is a bus data transmitter / receiver, 24 is a phase corrector, 25 is a baseband LSI, 26 is an ADPCM-CODEC in the baseband LSI 25, and 27 is a TDM.
A / TDD processing unit, 28 is a π / 4QPSK modem, 29
Is a radio unit, 30 is a bus, 31 is a CPU, 32 is a reference clock generation unit, 33 is a reference timing generation unit that generates a transmission / reception slot timing which is a reference timing and a synchronization timing of a TDMA / TDD frame, and 34 is a connection device 2. An engineering switch for setting a number, 35 is a memory, and 36 is an ID-which stores the CS-ID of the connection device 2.
ROM and 37 are power supplies. TDMA / TD shown in FIG.
The D frame is 5 mS, and is composed of 4 slots for transmission and 4 slots for reception. In principle, the connection device 2 and the handset 4 use the same carrier wave, and four calls can be simultaneously performed.
The reference clock in claim 1 is a 19.2 MHz clock transmitted from the reference clock generation means (reference clock generation unit 32 in Fig. 4). In addition, the reference timing of claim 1 indicates "transmit / receive slot timing" of 625 µS and "TDMA / TDD frame timing" of 5 mS.

First, the structure of the home telephone will be described with reference to FIG. The main unit 1 is an IS from the central office switch 10.
It accommodates a DN line (or telephone line, the same applies hereinafter).
The connection device 2 and the telephone set 14 are connected to the main device 1 through an extension bus 12. Further, the slave unit 4 is controlled by the main unit 1 via the connection unit 2 connected by a wireless line to the ISD.
It makes outgoing calls to the N line and receives incoming calls from the ISDN line. A part of the connection device 2, the slave 4, and the main device 1 for controlling the wireless line, that is, a part excluding the control of the telephone is referred to as a digital cordless telephone device 20.

Next, the operation of the connection device 2 of the present invention shown in FIGS. 3 and 4 will be described with reference to various signals shown in FIGS. Various signals are transmitted from the main device 1 to the connection device 2 through the extension bus 12. These signals are configured in a multiframe format as shown in FIG. The multiframe is composed of N basic frames each having frame number data, B channel data corresponding to each connecting device, D channel data for control, etc. at the beginning. The multi-frame signal of FIG. 2A supplied from the main device 1 to each connecting device 2 via the extension bus 12 reaches the bus data transmitting / receiving unit 23 through the bus connector 21. The bus data transmitter / receiver 23 receives the input multi-frame signal from FIG.
The multi-frame clock shown in (2) is generated and output to the reference timing generation unit 33. Further, the basic frame signal of 8 kHz shown in FIG. 2C is generated and output to the reference clock generator 32 and the phase corrector 24.

The reference clock generator 32 is a PLL circuit, and a reference clock generator 32 is used to adjust 8 kHz used as a PCM synchronizing signal between the baseband LSI 25 side and the phase corrector 24 to the basic frame signal 8 kHz from the bus data transmitter / receiver 23. Oscillation control of clock 19.2 MHz. In the baseband LSI 25, this reference clock 19.2
After receiving the supply of MHz, the frequency is divided to 8 kHz and returned to the reference clock generator 32. Reference timing generation unit 3
3, the reference clock 19.2 MHz input from the reference clock generator 32 is divided, and the TDMA / TDD processor 2
The transmission / reception slot timing of 625 μS, which is the synchronization signal shown in FIG.
CPU with 5ms TDMA / TDD frame timing
Output to 31.

The control data (indicated by D (N-1) in FIG. 2 (1)) on the multi-frame from the extension bus 12 is CP.
It is output to the bus 30 toward U31. Based on this control data that has arrived, the CPU 31 performs various controls and also controls the transmission of control data that is transmitted from the connection device 2 of its own to the main device 1. Further, the Bch data (voice data or data for data communication) in the multi-frame is sent from the bus data transmitter / receiver 23 to the phase corrector 24 in synchronization with the basic frame signal 8 kHz. Note that one connecting device 2 is shown in FIG.
Of the multi-frame Bch of (1), for example, B0 assigned to itself is taken in. In the phase corrector 24, this is replaced (synchronized) with the PCM synchronizing signal 8 kHz on the side of the baseband LSI 25 supplied from the baseband LSI 25, and the ADPCM in the baseband LSI 25 is changed.
-Sending to CODEC 26. Further TDMA /
In the TDD processing unit 27, this ADPCM-CODEC 26
Each 32 kbps data from the above is converted into a 384 kbps burst signal, and is assigned to one of the transmission slots indicated by CS1 in FIG. Send to 4QPSK modem 28. The π / 4QPSK modem 28 modulates the input signal and sends it to the radio unit 29. The radio unit 29 converts this signal into a transmission frequency and emits it as a radio wave from the antenna 3.

On the other hand, the radio unit 29, which has received the radio wave emitted from the slave unit through the antenna of the connection device 20, carries out the frequency conversion and then the π / 4QPS in the baseband LSI 25.
It is sent to the K modem 28. The signal demodulated by the π / 4QPSK modem 28 is arranged at the receiving slot position corresponding to the transmitting slot position as shown in FIG. TDMA
In the / TDD processing unit 27, contrary to the transmission data, 384 kb
The speed is converted from ps to 32 kbps, and the received data in the unique receiving slot position is detected, and further ADPCM-C
The ODEC 26 converts the data into 64 kbps data and sends the converted data to the phase corrector 24. Phase corrector 2
In 4, the received data from the baseband LSI 25 is replaced with the timing of the basic frame signal 8 KHz on the side of the bus data transmitter / receiver 23 and sent to the bus data transmitter / receiver 23. The CPU 31 sends the received data from the phase corrector 24 to the bus data transmitter / receiver 23, which corresponds to its own connection device B.
The control data from the CPU 31 is inserted into Dch at the position of ch to create a transmission multiframe (not shown) synchronized with the reception multiframe of FIG.
(Transmission line). In this way, in the digital cordless telephone device 20, each connection device 2 transmits / receives to / from the cordless handset 4 connected by a wireless line.

However, when a new home telephone is newly installed or when a power failure is restored, just by supplying power to each device, the transmission / reception slots between the connected devices are synchronized as in the case of the connection device of the conventional distributed processing system. Therefore, control to avoid radio wave interference between connected devices cannot be performed.

Therefore, in the present invention, the first step is as follows. Frame number F0 of FIG. 2 (1) on the main device 1 side
As an example, data for activating slot synchronization between connected devices is inserted once every 30 seconds in the reception timing RT in the basic frame of 1. CP of all connection devices 2
U31 is a reception timing R as data relating to control input from the extension bus through the bus data transceiver 23.
When the data of T is detected, it instructs the TDMA / TDD processing unit 27 in the baseband LSI 25 through the bus 30 to enter the standby state for the frame signal coming from the extension bus 12. Next, this reception timing RT
The multi-frame clock MFCK that responds at the beginning of B0 that is the Bch data following the frame number "F0" that is the beginning of the next multi-frame following the multi-frame where the relevant data was inserted into The data transmission / reception unit 23 outputs the reference timing generation unit 33. When the reference timing generation unit 33 is reset by the multi-frame clock MFCK, it newly starts output of the transmission / reception slot timing of 625 μS and the TDMA / TDD frame timing of 5 mS shown in FIG. 1 from that point. In the baseband LSI 25, a counter (not shown) starts counting the input signal (pulse) of 625 μS. The CPU 31 sends a reset signal for the counter to the baseband LSI 25 each time the input 5 mS signal (pulse) is input. Then, the counter of the baseband LSI 25 is cleared by the reset signal of 5 mS from the CPU 31 when it receives the signal of 625 μS eight times. Then, this operation is repeated. T
The DMA / TDD processing unit 27 synchronizes the transmission / reception slots based on the reference timing shown in FIG. That is, with this synchronization timing, a T of 5 mS composed of four transmission slots of 625 μS and four reception slots.
A DMA / TDD frame is generated. Since all the connecting devices perform the same operation as above at the same timing, the connecting devices are in a synchronized state as shown in FIG.

The second step of the present invention is as follows.
In this embodiment, each connection device 2 has a transmission / reception slot 1
It has the function of sending and receiving individual pieces. The time for one transmission / reception slot is 625 μS each. As shown in FIG. 1, the connection device 2 (CS1) uses the above-mentioned multi-frame clock MFCK extracted from downlink (reception) extension bus data.
The transmission slot is arranged at the same time as the reference time point of the reference timing, the next connection device 2 (CS2) arranges the transmission slot with a delay of 625 μS from the reference time point of the reference timing, and the next connection device 2 (CS3) is changed to the above. The transmission slot is arranged with a delay of 625 μS × 2 from the reference time point of the reference timing, and the connection device 2 (CS4) is arranged with the transmission slot being delayed by 625 μS × 3 from the reference time point of the reference timing.

The setting for this connecting device is performed by the setting switch 3 for the working note which sets a different number in the CPU 31 for each connecting device.
Set by 4. CPU31 is baseband LSI2
The TDMA / TDD processing unit 27 of No. 5 is controlled to operate with the delay time corresponding to the number of the connected device set.
As described above, each connection device that uses one transmission / reception slot does not overlap the timing of the transmission / reception slot with other connection devices. Also TDMA / TDD
The frame consists of 4 slots for sending and receiving,
When five or more connecting devices 2 are connected to the main device 1 and used, the same delay time as that of the first four devices divided into different slots is set. However, since there are a plurality of transmission and reception carrier frequencies that can be used, the wireless unit 29 detects whether or not another connection device is emitting a radio wave (carrier sense),
When a radio wave from another connecting device is detected, the frequency used can be changed before transmission / reception.

In the above embodiment, the control timing and the communication timing are not described separately, but the control timing is the superframe interval and the operation is the same.

[0016]

Although the connection device of the digital cordless telephone device of the present invention is a distributed processing system, even if a plurality of connection devices are connected so that each connection device uses a separate transmission / reception slot, radio wave interference will occur. Since it is eliminated, the number of connecting devices connected to the main device can be increased.

[Brief description of drawings]

FIG. 1 is a diagram showing a transmission / reception slot according to an embodiment of the invention.

FIG. 2 is a diagram showing (1) a multiframe coming from a reception line of an extension bus; (2) a diagram for extracting a multiframe clock from the multiframe; and (3) a diagram for extracting a basic frame signal from the multiframe.

FIG. 3 is a block diagram of a home telephone using a digital cordless telephone device.

FIG. 4 is a block diagram of a connection device.

[Explanation of symbols]

1 main device 2 connection devices (CS1-L) 3 antennas 4 cordless handsets (PS) 10 telephone exchanges 11 ISDN line 12 extension buses 14 telephones 20 Digital cordless telephone device 21 Extension bus connector 23 Bus data transceiver 24 Phase corrector 25 Baseband LSI 26 ADPCM-CODEC 27 TDMA / TDD processing unit 28 π / 4 QPSK modem 29 radio section 30 bus 31 CPU 32 Reference clock generator 33 Reference Timing Generation Unit 34 Engineering Note Switch 35 memory 36 ID-ROM 37 power supply

─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-9-149459 (JP, A) JP-A-6-303191 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04B 7/24-7/26 H04Q 7/00-7/38

Claims (2)

(57) [Claims] 1. A plurality of connecting devices connected to an extension bus from a main device of a home telephone or a key telephone device, and a plurality of slave units connected to these connecting devices by a wireless line using a TDMA / TDD system. In the provided digital cordless telephone device, a multi-frame clock is provided from the multi-frame signal of the downlink bus data sent from the main device through the extension bus, and means for generating a basic frame signal is provided, and the digital frame is generated by the basic frame signal. Reference clock generation means, means for receiving a reference clock of the reference clock generation means and generating reference timing,
After receiving the data inserted into the multi-frame signal of the downlink bus data and activating the slot synchronization between the connection devices, which is transmitted at a constant period, the means for generating the reference timing by the multi-frame clock is reset, At the same time as the reference time point of the reference timing, the other connection apparatus arranges the transmission slots with a delay of a positive integer multiple of the transmission / reception slot timing period from the reference time point, thereby phase-shifting between the connection apparatuses. A connection device for a digital cordless telephone device, characterized in that transmission / reception slot synchronization without deviation is performed by distributed processing on the connection device side. 2. When connecting devices having more than the number of transmission / reception slots to the main device, from the reference time point of the reference timing to its own transmission slot so that the number of overlapping transmission / reception slots without phase shift is minimized. 2. The digital cordless telephone device according to claim 1, wherein the connection device having the same time width as that of the other connection device and using overlapping transmission / reception slots without phase shift uses carrier sense to use different transmission frequencies. Connection device.