JPH06101785B2 - Wireless communication device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a wireless communication device.

2. Description of the Related Art Generally, in a unidirectional wireless communication system, two radios use the same frequency, and a station that wants to transmit transmits a signal at that frequency. For example, when one transceiver is in the transmitting state, that is, when transmitting a voice etc., the transceiver in the receiving state is usually in the transmitting state by operating the press talk switch attached to the microphone. Radio waves can be transmitted. When the partner station transmits, the same operation sets its own wireless device in the transmission state. If both are in the transmitting state at the same time, communication cannot be performed.

In this way, in one-way wireless communication, it is necessary to set the wireless device on the side to be transmitted to the transmitting state. To perform data communication such as facsimile communication using such a radio, it is necessary to automatically control the switching of the transmission state in order to transmit and receive complicated and various procedure signals for setting the connection. preferable. At that time, it is necessary that both sides are not in the transmission state at the same time, and the signal transmission side needs to properly match the timing of the period in which the radio is in the transmission state and the timing of the data transmission period. Furthermore, it is advantageous that the switching time is short from the viewpoint of communication efficiency.
On the other hand, data transmission / reception requires accuracy and certainty.

By the way, when a data communication device such as a facsimile is connected to a wireless device to control switching of one-way communication, the data communication device sends a control signal to the wireless device in a transmitting state to enable actual transmission. Since there is a time delay between the start of the transmitter radio and the detection of the received signal of the receiver radio, the output signal at the rise of the control signal is detected as a normal reception signal by the receiver. There are things you can't do. This results in lack of accuracy and certainty in data transmission and reception.

An object of the present invention is to solve the above-mentioned drawbacks of the prior art and to provide a wireless communication device with high operability that realizes reliable and accurate data communication.

According to the present invention, in order to achieve the above object, a radio unit for transmitting and receiving a signal with a radio wave of a predetermined frequency in response to a control signal, and a signal to be transmitted to the radio unit In addition, the data communication means includes a data communication means for receiving a signal transmitted from the wireless communication means, and a delay means for setting a time required for the wireless communication means to rise in response to the control signal. The means sends the effective portion of the signal to be transmitted to the wireless means after a lapse of a time set in the delay means after the control signal is given to the wireless means.

In this specification, the term "data" is to be interpreted in a broad sense, including not only digital data in a narrow sense, but also analog image information such as facsimile information and voice information. The above is a specific description based on an embodiment of the present invention.

Referring to FIG. 1, there is shown an embodiment in which the present invention is applied to facsimile communication. In this embodiment, the facsimile machine (FAX) 10 is connected to the wireless device 50 and constitutes a transmitting station TX, that is, a side for transmitting an image signal and a receiving station RX, that is, a side for receiving an image signal. In the present embodiment, the wireless device 50 has a function of transmitting and receiving radio waves of the same frequency with the antenna 52 and performing one-way communication in which transmission and reception are not established at the same time, and is normally configured to be in a receiving state, for example, It may be for business use. The wireless device 50 may be, for example, an MCA communication system in which the use of radio waves is time-limited.

A transmission data signal is sent from the facsimile device 10 to the wireless device 50.
It is interfaced with the TXD and a control signal CNT that puts the radio device 50, which is normally in the receiving state, in the transmitting state. In addition, the received data signal RX is transmitted from the wireless device 50 to the facsimile device 10.
Interfaced with D. In the present embodiment, the transmission / reception data signals TXD and RXD including facsimile image information are transmitted / received by a predetermined code modulation method in a base band, for example, a band of about 300 Hz to 3 kHz of a voice band.

More specifically, the radio device 50 may be a radio device that performs a normal voice call by inputting a microphone in the present embodiment, and therefore, the data signals TXD and RXD are frequencies in the voice band,
Data is transmitted to and received from the facsimile machine 10 with a predetermined signal level and impedance to the wireless device 50.

The radio device 50 is always in the receivable state, and the control signal CNT
Goes to a high level H, it becomes a transmission state. In the sending state,
A carrier wave of a predetermined band is transmitted, for example, by FM-modulating a carrier wave of a predetermined band by a baseband transmission data signal RXD input from the facsimile device 10, and in the receiving state, the antenna is
Demodulates radio waves received from 52 to receive baseband data signal
It has a function of outputting to the facsimile device 10 as RXD. Of course, the transmission data signal TXD or the reception data signal RXD
Contains a communication procedure signal, it is processed inside the facsimile device 10.

When the facsimile device 10 performs facsimile communication by the wireless device 50, the facsimile device 10 according to the present embodiment has a CC as shown in FIG.
It has the function of executing the protocol based on the G3 facsimile standard of ITT Recommendation T.30 and setting the facsimile communication with the partner station.

The procedure signal used in the protocol is transmitted with the wireless device 50 in the transmitting state. The facsimile device 10 judges the procedure signal, and the facsimile device 10 controls the radio device 50 to either transmit or receive.

The time relationship between the control signal CNT that puts the radio device 50 in the transmitting state and the signal to be transmitted will be described. Fax machine
It takes some time for the wireless device 50 to output the control signal CNT from 10 and change from the receiving state to the transmitting state. In addition, the wireless device 50 of the transmitting station TX enters the transmitting state, and after transmitting the signal, the wireless device 50 of the receiving station RX detects and demodulates the signal, and the signal is normally input to the facsimile device 10. It also takes time.

For example, when sending DCS and modem training signals from the transmitting station TX, the facsimile machine 10 uses the control signal CNT
Is output to the radio device 50, the radio device 50 is set to the transmission state, and the signal line
Output DCS and modem training signals to TXD.
Meanwhile, the receiving station RX is in a receiving state.

As shown in FIG. 6A, when the transmission data signal TXD is sent at the same time as the rising of the control signal CNT, the transmission data signal TXD is delayed due to the delay of the rising time t1 of the radio device 50 as shown in FIG. 6B. Would not be sent successfully. That is, the signal at time t1 is not transmitted normally, and the receiving station RX is not receiving this correctly, which causes malfunction of the device.

As a method for solving such a problem, the control signal CNT is transmitted to the radio unit 50 earlier than the transmission of the transmission data signal TXD by time t.
Give to. Alternatively, the control signal CNT may be raised earlier than the period L by leaving the period L in which the receiving station RX recognizes that the transmission data signal TXD is valid. In the latter case, the period t before the valid period L does not include valid signal contents, and the receiving station RX does not detect the rising portion of the received signal RXD as a valid signal.

More specifically, as shown in FIG.
When transmitting the procedure signal, the reference numeral 10 sets the control signal CNT given by the radio device 50 to the high level H, and then gives the transmission data signal TXD, that is, the procedure signal in this case to the radio device 50 after a predetermined time t has elapsed. .

This predetermined time t becomes at least substantially equal to the delay time until the facsimile device 10 of the transmission side TX gives the control signal CNT to the radio device 50 and the radio device 50 actually starts up, that is, the time t1 described above. Is set. It should be noted that, in addition to this, a setting should be made to be substantially equal to the time added with the delay time until the radio device 50 of the receiving side RX detects the received signal from the transmitting side TX and becomes actually ready for transmission. It is even more advantageous. This ensures that the transmission data signal TXD such as a procedure signal is transmitted.

Alternatively, as shown in FIG. 5, at the same time when the control signal CNT rises, the transmission data signal TXD is given from the facsimile device 10 to the radio device 50, and the part of the radio device 50 with a predetermined time length t from the start is removed. Alternatively, the portion of the effective period L may be surely transmitted. That is, the signal of the predetermined length t may be received and detected normally during the valid period L even if the signal is not received or detected. For example, in the case of a procedure signal, the valid period L is set to be equal to or longer than a specified time having a meaning as the procedure signal.

Here, the predetermined period t is generally the radio station 50 at the transmitting station TX.
It suffices that it is set to be substantially equal to the time delay from when the signal is activated by the high-level H control signal CNT to when the signal is actually ready to be transmitted. Since a delay occurs, it is advantageous to set the length including this time.

In this embodiment, the facsimile machine 10 also reads image information from a document after the communication connection with the partner station is set, compresses and encodes the image information by a predetermined encoding method, and modulates it by a predetermined modulation method. Then, it has a function of sending it as a transmission data signal TXD to the wireless device 50. Further, it has a function of performing code demodulation of the facsimile signal RXD received by the wireless device 50, decoding and decoding the facsimile signal RXD according to the same predetermined compression encoding method, and recording the visible image on the recording medium. In this embodiment, an encoding method, a decoding method, a modulation method, and a demodulation method based on the CCITT Recommendation G3 standard are advantageously applied to these, and the flow of the protocol is illustrated in FIG.

FIG. 3 shows an apparatus configuration part for realizing the functions related to the present invention among the functions of the facsimile apparatus 10. The image signal 14 from the document reading section of this device is
M) 12 is entered. The modulator / demodulator 12 is a modulator / demodulator that modulates a facsimile signal to be transmitted by a predetermined modulation method and demodulates a received facsimile signal. The functional units on the receiving side are not shown because they are not directly related to the understanding of the present invention.

The output 16 of the modulator / demodulator 12 is connected to a terminal 20 that outputs a transmission data signal TXD through an OR gate 18. The terminal 20 is connected to the transmission data signal input terminal of the wireless device 50.

The apparatus also has a procedure signal sending unit 22 for controlling the sending of the communication procedure signal, the output 24 of which is connected to the other input of the OR gate 18.

The functions and operations of these parts inside the device are controlled by the system controller.
Controlled by 28. The system control unit 28 in this embodiment is advantageously constituted by a processing system such as a microprocessor. The system control unit 28
An activation signal CNTA for putting the radio device 50 into a transmission state and an activation signal CNTA1 for operating the modulator / demodulator 12 are generated at terminals 30 and 32, respectively. Both terminals 30 and 32 are OR
It is connected to the control signal generator 36 via the gate 34.
The control signal generator 36 outputs a control signal CNT, whose output 38 is connected to the transmission control terminal of the radio device 50 and puts the radio device 50, which is normally in the receivable state, in the transmission state to the radio device 50 at a predetermined signal level It is a functional part that occurs in.

The terminals 30 and 32 of the activation signals CNTA and CNTA1 are also connected to the procedure signal sending unit 22 and the modulator / demodulator 12 via the delay unit 40, respectively. The delay unit 40 has a function of delaying the activation signals CNTA and CNTA1 applied to the inputs 30 and 32, respectively, by the delay time t described above, and outputting the activation signals CNTB and CNTB1 respectively. As can be seen from this, the procedure signal transmission unit 22 and the modem unit 12 are activated by the system control unit 28 using the activation signals CNTA and CNTA1 respectively.
Is started with a delay of time t from the occurrence of.

The system control unit 28 of the transmitting station TX calls the receiving station through the wireless device 50. In response to this, the receiving station RX sends a CED (called station identification) signal to the transmitting station TX under the control of the system control unit 28.
And then a DIS (digital identification) signal is returned.

These CED and DIS signals are transmitted after the above-mentioned predetermined time t, as shown in FIG. More specifically, the system control unit 28 of the receiving station RX first sets the activation signal CNTA to the high level H when transmitting a CED signal, for example. This activates the control signal generator 36 through the OR gate 34, whereby the radio signal 50 of the receiving station RX receives the control signal CNT of high level H from the control terminal 38. As a result, the wireless device 50 is activated and becomes ready for transmission.

On the other hand, the delay unit 40 delays the activation signal CNTB by a predetermined time t to form the activation signal CNTB, and thereby activates the procedure signal transmission unit 22. Therefore, the procedure signal transmission unit 22 generates a procedure signal in the sequence, that is, a CED signal in this example, and this is given from the output 20 to the wireless device 50 as the baseband transmission data signal TDX through the OR gate 18. The system control unit 28 keeps the activation signal CNTA at the high level H for a predetermined period required for identifying the CED signal (this corresponds to the valid period L in the example of FIG. 5). Meanwhile, the wireless device 50 maintains the transmission state.

In this way, the CED signal and the DIS signal are transmitted from the radio device 50 of the receiving station RX to the transmitting station TX. When the system control unit 28 of the transmitting station TX detects the CED and DIS signals, it sends a DCS (digital command) signal in response to this. This D
The CS signal is also transmitted by the method described above for the receiving station RX. That is, in this embodiment, as described above, the control signal CNT is transmitted after a predetermined time t from the rising edge of the control signal CNT.

After that, the system control unit 28 of the transmitting station TX transmits a predetermined modem training pattern signal to the receiving station in the same manner as a normal facsimile transmission control procedure, and performs training of the modulator / demodulator 12 of the receiving station RX. The transmission of this training pattern is performed as follows.

The system control unit of the transmission station TX first sets the activation signal CNTA1 to the high level H. This activates the control signal generator 36 through the OR gate 34, whereby the high level H control signal CNT is input from the control terminal 38 to the radio device 50 of the transmitting station TX.
Then, the wireless device 50 is activated and becomes ready for transmission.

On the other hand, the delay unit 40 delays the activation signal CNTA1 by a predetermined time t to form the activation signal CNTB1, and thereby activates the modulator / demodulator 12. Therefore, the system control unit 28 generates a pattern signal in the training sequence, which is
The output 20 is provided to the radio 50 through the OR gate 18 as the baseband transmission data signal TXD. System control unit 28
Is the activation signal for the predetermined period required for this training.
Keep CNTA at high level H. Meanwhile, the wireless device 50 maintains the transmission state.

When the receiving station RX finishes the training, the system control unit 28 returns a CFR (reception preparation confirmation) signal to the transmitting station TX. In the transmitting station TX, when the system control unit 28 detects the CFR signal, the radio unit 50 is set to the transmitting state in the same manner as described above, and the delay unit 40 activates the modulator / demodulator 12 after a predetermined period t. The system control unit 28 starts reading the original image information, and the image information or message read from the original is compression-encoded by the modulator / demodulator 12, assembled into a transmission frame, modulated, and transmitted through the OR gate 18 to a transmission data signal. It is transmitted to the wireless device 50 as TXD. This is transmitted from the radio device 50 to the receiving station RX.

At the receiving station RX, the radio 50 receives this message, the modulator / demodulator 12 demodulates it, deframes and reproduces the code.
Finally, it is output as a hard copy on the recording paper.

In this embodiment, the image information message for one unit, that is, one page in this embodiment is transmitted from the transmitting station. When the next transmission original does not exist, the system control unit 28 of the transmission station TX sends an EOP (end of procedure) signal in the end processing. This EOP signal is also transmitted similarly to the above. In response, the receiving station RX sends back an MCF (message confirmation) signal. When the transmitting station TX detects the MCF signal, it returns a DCN (disconnect command) signal to the receiving station RX to restore this connection.

It goes without saying that the present invention is effectively applied to data transmission in addition to such facsimile communication.

Effect According to the present invention, as described above, the transmission state is instructed to the one-way communication wireless device before the transmission of at least the effective portion of the information signal by the predetermined period. Therefore, the one-way communication radio can be used to reliably and automatically transmit the information signal including the communication procedure signal without losing the effective portion of the information signal to be transmitted. . Therefore, wireless data communication with high reliability and operability is realized.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing an embodiment in which the present invention is applied to a facsimile machine, and FIG. 2 is a G diagram of CCITT Recommendation T.30 according to the apparatus shown in FIG.
3 Flowchart showing an example of a facsimile communication control procedure according to the facsimile protocol, FIG. 3 is an explanatory view showing a specific configuration example of a part of the apparatus shown in FIG. 1, FIG. 4, FIG. 5, and FIG. 6A to 6C are waveform diagrams for explaining the operation of the embodiment shown in FIG. Explanation of symbols of main parts 10 …… Facsimile device 12 …… Modulator / demodulator 22 …… Procedure signal transmitter 28 …… System controller 30 …… Control signal generator 40 …… Delayer 50 …… Radio device

Claims (1)

[Claims] 1. A radio unit for transmitting and receiving a signal with a radio wave of a predetermined frequency in response to a control signal, and a signal to be transmitted to and transmitted from the radio unit. Data communication means for receiving an incoming signal, and delay means for setting a time required for the radio equipment means to start up by receiving the control signal, wherein the data communication means transmits the control signal by the radio signal. A radio communication device, characterized in that, after the time set in the delay means has elapsed after being given to the radio means, the effective portion of the signal to be transmitted is sent to the radio means.