JPS63237630A - Radio data transmitter - Google Patents

Abstract

PURPOSE:To always surely transmit data irrespectively of the length of time switching to the transmission action of a radio equipment by starting the transmission of data after the lapse of a prescribed length of time after the radio equipment is switched to the transmission mode. CONSTITUTION:A transmission timing control circuit 17, when a transmission instruction signal TRS from a communication control part 15 is turned on, allows a press talk signal PTT to be turned on and the radio equipment 4 to switch to the transmission made, also, allows a transmission permission signal ENA to be turned on after the lapse of a delay time T3. By the turning this signal on, the part 15 starts its data transmission. The radio equipment, even if the press talk signal PTT is turned on, needs a switching time T2 up to the transmission is possible, the delay time T3 is set longer than the time T2. As a result, even with a radio equipment whose switching time T2 is long, the data transmission can be surely executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a wireless data transmission device that performs data transmission using a wireless device that transmits and receives data by switching between a transmitting operation and a receiving operation.

[Prior art #i] A facsimile machine is one of data transmission devices. Additionally, wireless facsimile devices, such as in-vehicle facsimile devices, are known that use a wireless device to transmit data over a wireless line.

The wireless device used in such wireless facsimile devices is often used for one call, and in the process of transmitting one image, the wireless device is switched to sending operation only during data transmission, as in the case of a phone call. There is.

For this reason, the above switching is performed by extracting a transmission instruction signal from the wireless facsimile device indicating that it is in a data transmission state and inputting this signal to the wireless device as a breathtalk signal.

In this case, it usually takes a switching time of several 1011 Is to several 100 m5 for the wireless device to emit a carrier wave after the breathtalk signal is turned on until it becomes ready to actually transmit data.

However, when transmitting data, a conventional wireless facsimile machine waits for 1, for example, several Ils after turning on a transmission instruction signal.
Since data transmission is started later, there is a problem in that if a wireless device that takes a long time to switch to transmission operation is used, the beginning of the transmitted data may be lost, making it impossible to perform reliable data transmission.

[Objective] An object of the present invention is to provide a wireless data transmission device that solves the above-mentioned problem and can always perform reliable data transmission regardless of the length of time it takes for the wireless device to switch to transmission operation.

[Configuration] For this reason, the present invention provides a control means in the data transmission device for controlling the data transmission to start after a preset certain delay time has elapsed after switching to the transmission operation of the wireless device. .

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of a wireless facsimile system according to an embodiment of the present invention. In FIG. 1, a facsimile group @1 is an interface device i! to which a microphone stand 2 is connected. 3 to the wireless device i24. The interface device 3 is manually operated to connect the microphone stand 2 and the wireless device 4 during one call, and to connect the facsimile device 1 and the wireless device 4 during image transmission. The microphone stand 2 is provided with a microphone and a breath talk switch that is pressed while speaking. p, line equipment [! 4 is a known device generally used for telephone calls, and has a built-in speaker for listening to received audio.

1. In the facsimile apparatus 1, a scanner 11 reads an image of a transmitted document at a predetermined resolution, and a plotter 12 records and outputs a received image at a predetermined resolution.

The operation display section 13' consists of a display with a large degree of display flexibility for displaying various operation keys and operation guidance information, etc., and is used for the operator to operate this facsimile machine. The unit 14 has a function of encoding and compressing image data and a function of decoding the encoded and compressed image data into original image data.

The communication control unit 15 executes a predetermined transmission control procedure.

The modem 16 modulates the data to be transmitted and outputs it as a transmission data signal SD to the interface device [3], and also demodulates the reception signal input as a reception data signal RD and outputs the reception data. It is to take out.

The transmission timing control circuit 17 controls the transmission timing control circuit 17 when the facsimile [1] sends data to the wireless device! [4] is switched to the transmitting operation, and after the switching, the communication control section 15 is controlled so that the wireless device [4] waits for a certain period of time until it becomes capable of transmitting a signal, and then actually transmits data. For this reason, the signal conversion circuit 1 that outputs the breathtalk (signal PTT) signal that is turned on during data transmission (signal conversion circuit 1 that converts the transmission instruction signal TR5 from the control unit 15 and switches the wireless device 4 to transmission operation)
7a, and a delay circuit 17b that outputs a transmission permission signal TEN^ to the control unit 15 once a set predetermined period of time has elapsed when the transmission instruction signal TR5 is turned on.

The delay time setting switch 18 is used to set the delay time in advance according to the characteristics of the wireless device 4.

The system control section 19 controls each of the above sections in order to perform predetermined facsimile communications.

Consider transmitting image information between these wireless facsimile systems with the above configuration. first.

During transmission/reception standby, the interface device 3 connects the microphone stand 2 to the wireless device [! 4, and the operator of the transmitting station TX places the original to be transmitted on the scanner 11 of the facsimile group [1] of his own station, calls the operator of the receiving station RX by talking through the microphone and speaker, and starts image transmission. We will notify you that we will do so.

In this way, when the facsimile transmission is confirmed by both operators, each operator connects the interface device 3 of his own station to the facsimile machine! At the same time, the operator of the transmitting station TX causes the transmitting station TX to start the transmitting operation, and the receiving station RX operator causes the receiving station to start the receiving operation.

Thereby, the system control unit 19 of each of the transmitting station TX and the receiving station RX instructs the communication control unit 15 to start a transmitting operation and a receiving operation, respectively.

Upon receiving this command, the peripheral communication control unit 15 starts executing a predetermined transmission control procedure.

By the way, in this transmission control procedure, the procedure signal ps transmitted between the transmitting station TX and the receiving station RX is as follows: PSa~PS
There are five types up to f. This procedure signal PS is shown in Fig. 2 (
As shown in a), for example, 8-bit command data CM indicating information content is repeatedly and continuously transmitted for a fixed time Tl of about 1 second.

Each procedure signal PSa=PSf is transmitted in the following manner in the order shown in FIG. 4(b). That is, the communication control unit 15 of the receiving station RX first turns on the transmission instruction signal Tll5 as shown in FIG. 3(a) in order to transmit the procedure signal PSa. As a result, the signal conversion circuit 17a is
Turn on the breath talk signal PTT as shown in . This breath talk signal PTT is transmitted to the interface device i! I3
is input to the wireless device 4 via. The FI-line device 4 switches to transmitting operation when the breathtalk signal PTT is turned on, but until the carrier wave is actually emitted as a radio wave and the data signal can be transmitted, there is a constant delay as shown in FIG. The switching time T2 is required.

On the other hand, after the transmission instruction signal TrlS is turned on, the delay circuit 17b turns on the transmission permission signal ENA after the delay time T3 has elapsed, as shown in FIG. 3(d). This delay time T3 is.

The delay time setting switch 18 is set in advance to be longer than the switching time T2.

When the communication control unit 15 turns on the transmission permission signal IENA.

The procedure signal PSa is output at the timing shown in FIG. 4(e). This signal PSa is transmitted to the modem 16. Wireless equipment via interface device 3! Sent from I4. In this procedure signal PSa, command data CM indicating the recording paper size of the own device, etc. is set, and ccrr digit recommendation T, 3Oj
Information corresponding to the DIS signal with R rating is transmitted.

At the transmitting station TX, this procedure signal PSa is transmitted by the wireless device 4.
is received and the interface device t3. The signal is input to the communication control section 15 via the modem 16. The communication control unit 15 receives command data CM that is repeatedly sent out over a certain period of time Tl, and if the same data is not received each time, the content is determined by majority decision. This process is to prevent malfunctions even if a transmission error occurs in a wireless line with an unstable communication state, and each subsequent procedure signal PSa"PSf is determined in this way on the receiving side. .

Next, in the transmitting station TX, the 1 communication control unit 15 switches the wireless device 4 to the transmitting state, and after a certain period of time T3 has elapsed, similarly to the operation at the receiving station rlX described above, the 1 communication control unit 15 transmits the procedure signal Psb. In this procedure signal PSb, command data CM corresponding to the DC5 signal is transmitted. Next.

For modem training // I II or 11
A fixed signal indicating 0'g is sent for a certain period of time.

In the following operation, the transmitting station TX and the receiving station Rx:
In this way, the wireless device 4 is switched to the transmitting operation and the delay time T
, l have elapsed, it operates to transmit predetermined data. Further, each procedure signal PSa''PSf corresponds to the specific g in the T and 30jljI cases, respectively, as shown below.

After executing modem training using the modem training signal, the receiving station FIX sends out a procedure signal PSc corresponding to the CFr1 signal.

When the transmitting station TX receives this, it reads out the image information using the scanner 11, encodes the image information using the encoding/decoding section 14, modulates it using the modem 16, and transmits it. When the sending of the image information is finished, [EO
A procedure signal PSd corresponding to the M signal is sent out.

The receiving station RX demodulates the image information using the modem 16,
The encoder/decoder 14 decodes the data, and the plotter 12 records it on recording paper. Then, a procedure signal Pse corresponding to the MCF signal indicating reception OK is sent out. When the transmitting station TX receives this signal, it sends out a procedure signal equivalent to the DCN signal indicating one line disconnection and ends the transmitting process, while the receiving station RX receives this signal and ends the receiving process.

As described above, in this embodiment, when the transmission instruction signal TR5 from the 1 communication control unit 15 is turned on, the transmission timing control circuit 17 turns on the breath talk signal PTT to switch the wireless device 4 to the transmission operation, while delaying After time T3 has elapsed, the transmission permission signal ENA is turned on, and when this signal is turned on, the communication control section 15 starts data transmission. Even if the breath talk signal PTT is turned on, the wireless device 4
A switching time T2 is required until data transmission is actually possible, but by setting the delay time T3 to be longer than the switching time T2, data transmission can be performed reliably even with a wireless device that has a long switching time T2. become.

Although this embodiment describes an example of a wireless data communication system that performs facsimile communication, the present invention is also applicable to various wireless data communication systems that use a wireless device to transmit data between a computer and a terminal device, for example. Needless to say, it can be similarly applied to.

[Effects] As described above, according to the present invention, data transmission is started after a preset period of time after the wireless device is switched to the transmitting state, so the length of time it takes to switch the wireless device to the transmitting operation can be adjusted. Regardless of the situation, data transmission can always be performed reliably.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a facsimile system according to an embodiment of the wireless data transmission device of the present invention, and FIG. 2(a)
is an explanatory diagram showing the signal format of the procedure signal;
) is an explanatory diagram of the transmission control procedure during image transmission, and FIG. 3 is a time chart showing each timing of transmission/reception switching of the wireless device and data transmission. 1... Facsimile device, 2... Microphone stand, 3... Interface device, 4... Wireless device. 11...Scanner, 12...Plotter, 13...
Operation display section, 14... Encoding/decoding section, 15... Communication control section, 16... Modem, 17... Transmission timing control circuit. 17a... Signal conversion circuit, 17b... Delay circuit,
18...Delay time setting switch. Figure 2 (b) (a) TR5 (e) Extended δ data Figure 3 - "-11] -

Claims (2)

[Claims] (1) In a wireless data transmission device that performs data transmission using a wireless device that switches to transmitting operation only when transmitting data, a transmitting/receiving switching means that switches the wireless device to transmitting operation, and data transmission delay means for delaying the start point of data transmission;
1. A wireless data transmission device comprising: delay time setting means for arbitrarily setting a time for delaying the transmission start point. (2) The wireless data transmission device according to claim 1, wherein the wireless data transmission device is a wireless facsimile device.