JP2517412B2 - Facsimile broadcasting receiver - Google Patents

Description

TECHNICAL FIELD The present invention relates to a facsimile broadcast receiving apparatus that receives a facsimile signal multiplexed in a television broadcast.

(B) Conventional technology Since the 1940s, a facsimile broadcasting system has been studied in which fixed images such as characters, figures, and photos are transmitted using television broadcasting waves and reproduced and recorded at the receiving side (Journal of the Television Society of Japan 87 In February 1991, two methods, analog method and digital method, were reported to the Minister of Posts and Telecommunications.

Among them, the digital system is sent out at a transmission rate of 16 kbps with a frame having a structure as shown in FIGS. In FIG. 5, the control signals such as MC (mode control signal) and PFX (prefix) and the portion (DAT) excluding CHC (error correction code) and FC (frame synchronization code) are data compressed by run length coding. Image signal. Next, FIG. 7 shows a conventional configuration example of a digital facsimile broadcast receiver. In FIG. 7, the television tuner (2) selects a desired channel of the television signal received from the television antenna (1), and the demodulation circuit (3) extracts and demodulates the facsimile signal multiplexed with the audio signal. It is converted into a digital signal sequence. The frame timing of this digital signal sequence is detected by the frame synchronization circuit (4), and the de-scramble, de-interleave processing, error in the de-scramble, de-interleave circuit (5) and error correction circuit (6) are performed in frame units. The image signal that has been corrected and then compressed by the composite circuit (7) is expanded and recorded by the printer (8). CPU (Process ROM and RAM for primary storage
(9) controls the operation of the facsimile receiving apparatus by identifying the control signal shown in FIG.

(C) Problems to be Solved by the Invention Conventionally, in the case of configuring a facsimile broadcast receiver, generally, a configuration including a tuner, a signal processing circuit, and a printer is included as shown in FIG. However, the thermal print head and the mechanical system for recording occupy a considerable part of the cost. As a result, even if efforts are made to reduce the cost by making a complicated signal processing circuit into an IC, there is a limit to the price reduction.

On the other hand, in the digital facsimile broadcasting, the image signal is compressed by the same method as that of the telephone facsimile, so that the decoding circuit (7) and the printer (8) are shown in FIG.
This part can be configured with the same circuit and mechanism as existing telephone facsimiles.

In digital facsimile broadcasting, the fifth
The image signal is transmitted by configuring the frame shown in the figure, and the effective transmission rate of the image signal excluding the control signal and error correction code is about 9760.83 bps. On the other hand, since the transmission speed of the image signal of G3 facsimile is 9600bps, the existing facsimile machine can be used by adding some additional circuits.

The present invention is intended to provide a low-cost facsimile broadcast receiving apparatus that enables the existing telephone facsimile apparatus to be used as it is.

D) Means for Solving the Problems The present invention relates to a tuner for selectively receiving a television broadcast, a demodulation circuit for extracting a shacky millimeter signal multiplexed into a sound signal of the television broadcast and converting the signal into a digital signal sequence, and the digital signal. In a facsimile broadcast receiving apparatus having a signal processing circuit for detecting a frame timing from a sequence, performing error correction, etc. and obtaining a code sequence of a facsimile image, a facsimile capable of receiving at least an image signal through a telephone line and printing a received image An image signal transmission control circuit, which is provided between the apparatus and the signal processing circuit, generates a start-up and communication control procedure signal for the facsimile apparatus, and transmits the facsimile image signal from the signal processing circuit to the facsimile apparatus according to this control procedure. Equipped with the fax machine Is characterized in that Shirushiutsushi the Kushimiri image signal.

(E) Operation According to the above means, the facsimile image signal from the signal processing circuit is received as a normal facsimile signal by the facsimile machine transmitted to the facsimile machine according to the transmission control procedure by the image signal transmission control circuit, and is printed. .

F) Example One example of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration example of a facsimile broadcast receiving apparatus according to the present invention. In FIG. 1, the same components as those in FIG. 7 are designated by the same reference numerals and the description thereof will be omitted. Reference numeral (10) is a signal processing circuit unit comprising the frame synchronization circuit (4), descrambling, deinterleaving circuit (5) and error correction circuit (6) in FIG. Further, (11) is a buffer memory and (12) is a speed conversion circuit, which will be described in detail later. (13)
Is a switch circuit, (14) is a voice band modem used in a telephone network, and (15) is a line control circuit. Also (16)
Is a connector for connecting an existing G3 facsimile machine (19), (17) is a keyboard for setting the state of the receiver, and (18) is a display.

Since the effective transmission speed of the facsimile image signal obtained by the signal processing circuit (10) is about 9760 bps as described above, the speed conversion circuit (12) directly inputs it to the modem and sends it to the G3 facsimile device (19). Even if it is not received, the output of the signal processing circuit (10) is stored in the buffer memory (11).
The data is read out sequentially at an appropriate timing while being recorded on the disk, and is sent out as 9600 bps serial data which can be received by the G3 facsimile apparatus. An example of the structure is shown in FIG. That is, the speed conversion circuit is mainly composed of the write address counter (20) and the read address counter (21). The facsimile image signal input to the buffer memory (11) includes control signals such as MC (mode control signal) and PFX (prefix) and CHC (error correction code) and FC (frame) as shown in FIGS. Since the sync code is included, the write address counter (20) uses a 16 KHz write clock signal to extract only the DAT part from these and write it to the buffer memory.
However, as shown in FIG. 3, the signal for operating the counter at the timing of the DAT section as the ENABLE signal is the signal processing circuit (1
0). On the other hand, the read address counter (2
The modem (14) supplies a read clock of 9600 bps to 1). In this way, the speed conversion circuit writes only the DAT section in the buffer memory and reads it at 9600 bps.

Further, the write address counter (20) and the read address counter (21) are reset by being supplied with a reset signal obtained by detecting the top of the page by the CPU (9).

The buffer memory (11) requires a sufficient memory capacity so that data is not lost because the writing speed is faster than the reading speed. In this case, about 161 extra bits are generated per second due to the speed difference, so most originals can be sent within 5 minutes. Therefore, use a memory that can absorb 161 x 60 x 5 = 48300 bits, for example, 64 kbit RAM. .

Further, the line control circuit (15) generates a predetermined DC voltage and superimposes it on the G3 facsimile apparatus (19) because the G3 facsimile apparatus (19) needs to be activated in the same state as the incoming state of the telephone line. The circuit includes a circuit for generating a ring signal (telephone call signal), and may have a well-known configuration used in a public telephone network or an exchange.

Further, the switch (13) is controlled by the CPU, and an image signal obtained from the speed conversion circuit (12) for exchanging signals according to the procedure (CCITT recommendation T.30) for operating the G3 facsimile apparatus (19), The serial data (transmission procedure control signal of G3 facsimile) output from the CPU (9) is switched and input to the modem (14). The modem (14) complies with CCITT Recommendations V.21 and V.29 in order to generate a signal compatible with G3 facsimile.

The buffer memory (11), speed conversion circuit (12), modem (14), line control circuit (15) and CPU (9) are used to activate and communicate the image signal transmission control circuit of the present invention, that is, the facsimile machine (19). A control circuit for generating a control procedure signal and transmitting the facsimile image signal from the signal processing circuit (10) to the facsimile device (19) is constructed in accordance with this control procedure.

The operation of the embodiment having the above configuration will be described. In facsimile broadcasting, control signals (MC) such as program numbers and page numbers are sent in addition to image signals, and the basic operation of the receiver is standby reception of preprogrammed programs.
An example of the operation of the receiver in this case is shown below. Normally, the receiving device stands by in a line disconnection state by the line control circuit (15). The CPU (9) monitors the received control signal, and when the desired program number is detected, controls the line control circuit (15) and starts the G3 facsimile in the phase A procedure (call setting procedure). , And switches the switch (13) to the lower side to exchange signals with the G3 facsimile in the procedure of phase B (procedure performed prior to message transmission after call setup). After the end of phase B, the CPU switches the switch (13) to the upper side, and the image signal received in the phase C procedure (message transmission procedure) and stored in the buffer memory (11) is converted to the speed conversion circuit (12) → modem ( 14) → Send it to the G3 facsimile machine (19) through the line control circuit (15) and have it printed by the facsimile machine (19). When the transmission of the image signal for one page is completed, the process shifts to phase D (the procedure of confirming that the message transmission is completed), and when the program is completed, the initial state of line disconnection is returned by the phase E manual recovery procedure). ,
Wait for the next show.

Next, FIG. 4 shows another embodiment in which a single G3 facsimile machine can be used for telephone threads and broadcasting type facsimile machines. The line control circuit (15) and the facsimile machine (19) are connected to each other. A change-over switch (22) is provided between them, and by changing over the change-over switch (22), the facsimile device is connected to the telephone line (23) or the line control circuit (15) of the receiving device.
It is configured to selectively connect to and. The changeover switch (22) may be configured to receive the detection signal of the incoming call detection circuit (24) and be changed over by the CPU (9) so that the telephone system can be preferentially received, or the facsimile broadcasting system is prioritized. It may be configured so that it can be received selectively. Further, the changeover switch (22) may be configured to be manually changed over.

However, it is possible to send the received image signal of the facsimile broadcast as it is to the telephone line (23) depending on how the changeover switch (22) is connected. However, in the above-mentioned embodiment, a problem under copyright law is taken into consideration. However, the switch configuration is such that this cannot be done. That is, the movable terminal (22a) is G
3 Connect to the connection terminal (24) of the fax machine (19),
Connect the fixed terminal (22c) to the connection terminal (2) of the telephone line (23).
5) and the other fixed terminal (22b) is connected to the line control circuit (15).

Next, FIG. 5 shows the main part of another embodiment of the present invention, and the difference from the embodiments of FIGS. 1 and 4 is the configuration of the line control circuit (15). That is, in this embodiment, unlike the above embodiment, a tone signal of a single frequency, for example, 1300 Hz is used instead of the ring signal of 16 Hz as means for activating the facsimile machine (19) (phase A). ing. Of course, in this case, as the facsimile device (19), one which can be activated by this tone signal is used. In addition, most of the commercialized facsimile machines have 13
It can be activated by a tone signal of 00Hz. In Fig. 5, (26) is a 48V provided to make the state similar to a telephone line.
Power supply circuit, (27) is a 1300Hz tone signal generation circuit,
(28) is a transmission / reception amplifier, and (29) is a transformer for telephone lines. (30) is a terminal connected to the facsimile machine side. In many cases, the power supply circuit (26) can be omitted because the facsimile machine can be started up without it. In addition, since the 1300 Hz tone signal can usually be generated by the modem (14), the tone generation circuit (2
7) can also be omitted. Further, as the tone signal, not a single frequency but a tone signal composed of a combination of a plurality of frequencies, for example, dual tone (DTMF) may be used.

Furthermore, the present invention is not limited to the above embodiment, and the facsimile device need not be G3, for example. However, G3 is the most suitable as a facsimile device to be connected to a receiving device that conforms to the reported digital facsimile broadcasting system, considering its popularity, price, and transmission speed.

According to the present invention configured as described above, in the facsimile broadcast receiving apparatus, the print head and the mechanism system for recording, which occupy a considerable part of the cost, are provided in the existing telephone line facsimile apparatus. And a low-priced facsimile broadcasting receiver can be realized.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention,
FIG. 1 is an electrical block circuit diagram, FIG. 2 is a detailed configuration diagram of a main part of FIG. 1, FIG. 3 is an operation explanatory diagram of FIG. 2, and FIG. 4 is an electrical diagram of another embodiment of the present invention. 5 is a schematic block circuit diagram, and FIG. 5 is an electric circuit diagram of a main part of another embodiment of the present invention.
FIG. 7B is a diagram showing a frame structure of digital facsimile broadcasting, and FIG. 7 is an electrical block circuit diagram of a conventional example. (2) Tuner, (3): Demodulation circuit (9): CPU (10): Signal processing circuit, (11): Buffer memory (12): Speed conversion circuit, (14): Modem (15): Line control circuit

 ─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-64-73968 (JP, A) JP-A-2-202263 (JP, A) JP-A-63-300668 (JP, A) JP-A-64- 27359 (JP, A) Actually developed 52-64724 (JP, U)

Claims (4)

(57) [Claims] 1. A tuner for selectively receiving a television broadcast, a demodulation circuit for extracting a facsimile signal multiplexed with an audio signal of the television broadcast and converting it into a digital signal series, and detecting frame timing from the digital signal series,
In a facsimile broadcast receiving device having a signal processing circuit for performing error correction and obtaining a code sequence of a facsimile image, a facsimile device capable of receiving at least an image signal through a telephone line and printing a received image, and the signal processing circuit. In the meantime, there is provided an image signal transmission control circuit for generating a facsimile control signal for activating and communicating the facsimile device and transmitting the facsimile image signal from the signal processing circuit to the facsimile device according to this control procedure. A facsimile broadcast receiving apparatus characterized by printing a facsimile image signal. 2. The facsimile broadcast receiving apparatus according to claim 1, wherein the facsimile apparatus is of G3 standard, and the image signal transmission control circuit outputs a voice band modem used in a telephone network and a ring signal. A ring signal generating circuit for generating and a code sequence of a facsimile image obtained by the signal processing circuit are sequentially written, and are transmitted from the buffer memory at a signal speed suitable for the buffer memory and the facsimile device capable of reading at a proper timing. A facsimile broadcasting receiver including a speed conversion circuit. 3. The invention according to claim 1, wherein the facsimile apparatus is of G3 standard, and the image signal transmission control circuit generates a tone signal and a voice band modem used in a telephone network. A tone signal generating means, a buffer memory capable of sequentially writing a code sequence of a facsimile image obtained by the signal processing circuit and reading it at an appropriate timing, and a speed conversion for sending out from the buffer memory at a signal speed suitable for the facsimile machine. A facsimile receiver that includes a circuit. 4. The facsimile broadcast receiving apparatus according to claim 3, wherein the modem includes tone signal generating means.