JP2000156669A - Channel multiplex/demultiplexing method, channel multiplexer circuit and channel multiplexer/ demultiplexer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a channel multiplexer/demultiplexer that multiplexes a channel and transmits multiplexed data to adopt a coding method to realize a stable circuit operation, thereby attaining channel selection with a simple circuit. SOLUTION: A coding circuit 4 at a transmitter side conducts coding of data of each channel and insertion of a specific character specific to each channel, a character multiplexer circuit 5a applies byte multiplexing to each channel and transmits the multiplexed data, a character synchronization circuit 9 of a receiver side detects the specific character to take character synchronization, a character demultiplexer circuit 10a separates the data into each character byte to obtain data of each channel. Then a channel recognition circuit 11 detects the specific character specific to the channel without bit rotation for the synchronization to recognize a channel and a decoding circuit 14 decodes the data without the bit rotation and the channel demultiplexer circuit provides an output.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a channel multiplexing transmission apparatus for multiplexing and transmitting a plurality of channels. Regarding separation.

[0002]

2. Description of the Related Art As a conventional channel demultiplexing apparatus of this kind, for example, Japanese Patent Laid-Open Publication No.
The following configuration has been proposed. Here, a case where four channels are multiplexed is shown.

[0003] Referring to FIG. 9, a transmitting apparatus 108 on the transmitting side is used.
, An 8-bit parallel image signal 101 and a 1-bit serial frame signal 103 for each bit parallel
And the 9-bit parallel signal is 9
The signal is converted into a 10-bit parallel signal by the B10B encoding circuit 102.

[0004] One frame signal generator 104 for generating a frame signal 103 is assigned to each channel, and the frame signal 103 has a common frame pattern and includes a data signal in the frame pattern. .

[0005] The frame signal 103 is used for synchronization and also for identifying each channel.

[0006] The 10-bit parallel signal of the channel output from the 9B10B encoding circuit 102 is converted into a serial signal by a 10: 1 parallel-serial conversion circuit 105, and this serial signal is further converted by a 4: 1 parallel-serial conversion circuit 106. The signals are multiplexed between channels and input to the transmitter 107, and the
Is transmitted to the transmission path.

[0007] In the receiving device 116, the receiver 109
Receives the transmission signal, is shifted into the serial / parallel conversion circuit 110 by the clock signal from the hunting circuit 115, and the 10-bit parallel signal corresponding to the channel is sequentially input to the 10B9B decoding circuit 111 corresponding to the channel.

The output 9 of the 10B9B decoding circuit 111
The bit parallel signal is separated into an 8-bit parallel image signal and a 1-bit frame signal, and the frame signal of each channel is input to the corresponding synchronization detection circuit 112 to be used for frame synchronization detection. The synchronization detection circuit 112 compares, for example, an input bit string (9 bits) with a predetermined synchronization pattern, outputs a synchronization detection signal when they match, and when no synchronization pattern is detected, notifies the synchronization protection circuit 114 of the fact.
To send to.

The frame synchronization operation is performed by each synchronization detection circuit 112.
Of the outputs selected by the channel selection circuit 113 are input to the synchronization protection circuit 114 to synchronize the frames.

When frame synchronization is not achieved in the synchronization protection circuit 114, the hunting circuit 115 shifts the phase of the clock for driving the serial-parallel conversion circuit 110 by a predetermined amount, and outputs the 10-bit data output from the serial-parallel conversion circuit 110. This operation is continued until the parallel signal becomes a 10-bit parallel signal corresponding to each channel.

[0011]

As described above,
In a conventional channel multiplexing and transmission system, since a 1-bit frame signal is added together with a data byte parallel signal, the encoding bytes become irregular, and unique encoding is required.

Also, since the decoded frame signal is a serial signal, the synchronization detection circuit on the receiving side converts this frame signal in parallel and performs bit rotation (cyclically shifts the bit position, for example, MSB (most significant bit). )), The bit patterns are compared while the bits overflowing from the LSB side are inserted from the LSB (least significant bit) side. For this reason, it takes time to detect synchronization, and a double bit rotation function (frame signal extraction in 10B9B decoding and pattern detection of synchronization detection) is required.

Accordingly, the present invention solves the above-mentioned problems of the prior art, and in a channel multiplexing / demultiplexing apparatus for multiplexing and transmitting channels, an encoding method is used to realize stable circuit operation, and channel selection is performed by a simple circuit. An object of the present invention is to provide a channel multiplexing / demultiplexing device capable of operating.

[0014]

In order to achieve the above object, a channel demultiplexing method according to the present invention is a method for demultiplexing a plurality of channels.
Bit to n bits (m and n are predetermined integers, where m <
n) Encode the channel using an encoding method to encode, and each of the channels has 1 bit of n bits.
Or inserting a plurality of channel recognition bytes into each of the channels at a common interval, and multiplexing the signal into which the one or more channel recognition bytes have been inserted, wherein the channel recognition bytes are normally used for encoding in the encoding method. This code is not used for output, and is characterized in that the channel is recognized by detecting the channel recognition byte at the time of channel separation.

The channel multiplexing / demultiplexing apparatus according to the present invention employs an encoding method for encoding transmission data of each channel from m bits to n bits (m and n are predetermined integers, where m <n). Means for encoding transmission data every time,
Means for inserting one or a plurality of channel recognition bytes of n bytes into one byte into each of the encoded transmission data at a common interval to each channel, and multiplexing the transmission data with the channel recognition bytes inserted therein; Means for detecting the channel recognition byte from the received signal to synchronize characters for decoding, and recognizing each channel from the channel recognition byte inserted in the character synchronized reception signal. And means for separation,
The channel recognition byte is a code that is not normally used for output in the encoding method, and is a special character composed of one or a plurality of combinations for uniquely identifying the channel and also for character synchronization. And

The first channel multiplexing circuit of the present invention converts transmission data of each channel from m bits to n bits (m, n
Is a predetermined integer, where m <n) means for encoding the transmission data for each of the channels using an encoding method for encoding, and each of the encoded transmission data includes one byte of n bits. Means for inserting one or a plurality of channel recognition bytes into each of the channels at a common interval, and means for time-division multiplexing the transmission data into which the channel recognition bytes have been inserted with n bits as one byte, The channel recognition byte is a code that is not normally used for output in the encoding method, and is a special character composed of one or a plurality of combinations for uniquely identifying the channel and also for character synchronization. And

The second channel multiplexing circuit of the present invention converts transmission data of each channel from m bits to n bits (m, n
Is a predetermined integer, where m <n) means for encoding the transmission data for each of the channels using an encoding method for encoding, and each of the encoded transmission data includes one byte of n bits. Means for inserting one or more channel recognition bytes into each of the channels at a common interval, and means for time-division bit multiplexing the transmission data into which the channel recognition bytes have been inserted, wherein the channel recognition bytes are: The encoding method is a code that is not normally used for output, and is a special character composed of one or a combination of a plurality of combinations that uniquely identifies the channel and also serves for character synchronization.

The channel multiplexing / demultiplexing apparatus of the present invention receives a first channel multiplexing circuit and transmission data from the first channel multiplexing circuit, detects the special character, synchronizes the characters, and sets n bits for each character. A character synchronizing circuit for outputting as a parallel signal, a separating circuit for inputting an n-bit parallel signal output of the character synchronizing circuit, and separating each of the time-division multiplexed channels as n-bit 1 byte, and an output of the separating circuit And a decoding circuit for inputting and decoding each channel from the inserted special character and each output of the recognition circuit.

The channel separation and multiplexing apparatus of the present invention receives a first channel multiplexing circuit and transmission data from the first channel multiplexing circuit, detects the special character, synchronizes the characters, and sets n bits for each character. A character synchronizing circuit for outputting as a parallel signal, a decoding circuit for inputting and decoding an n-bit parallel signal output of the character synchronizing circuit, and an m-bit parallel signal output for inputting the m-bit parallel signal output of the decoding circuit;
A separation circuit that individually separates each channel time-division multiplexed as one byte of a bit, a channel recognition circuit that receives an output of the separation circuit, and recognizes each channel from the decoded special character; And a terminating circuit for receiving each output of the above and terminating the decoded special character.

A channel multiplexing / demultiplexing apparatus according to the present invention includes a second channel multiplexing circuit, a separation circuit which receives transmission data from the second channel multiplexing circuit, and separates each of the time-division multiplexed channels. A character synchronizing circuit for inputting each output of the separation circuit, detecting the special character and performing character synchronization, and a channel for inputting the output of the character synchronizing circuit and recognizing each channel from the detected special character It is characterized by including a recognition circuit and a decoding circuit for inputting and decoding each output of the channel separation circuit.

The channel multiplexing / demultiplexing apparatus of the present invention receives a first channel multiplexing circuit and transmission data from the first channel multiplexing circuit, detects the special character, synchronizes the characters, and sets n bits for each character. A character synchronizing circuit for outputting as a parallel signal, a channel recognizing circuit for recognizing a time slot of a byte having n bits forming one channel as one byte from the detected special character, and an n-bit parallel signal output of the character synchronizing circuit And a decoding circuit for inputting and decoding each output of the demultiplexing circuit based on the information of the channel recognition circuit. And

The channel multiplexing / demultiplexing apparatus according to the present invention receives a first channel multiplexing circuit and transmission data from the first channel multiplexing circuit, detects the special character, synchronizes the characters, and sets n bits for each character. A character synchronizing circuit for outputting as a parallel signal, a channel recognizing circuit for recognizing a time slot of a byte having n bits forming one channel as one byte from the detected special character, and an n-bit parallel signal output of the character synchronizing circuit A separating circuit for inputting and decoding an m-bit parallel signal output of the decoding circuit, and separating each of the time-division multiplexed channels individually based on information of the channel recognition circuit; And a terminating circuit for receiving each output of the separating circuit and terminating the decoded special character. That.

[0023]

The principle of the channel demultiplexing method according to the present invention is as follows.
This will be described with reference to the timing chart of FIG. In addition,
Hereinafter, a case where two channels are multiplexed in a channel multiplexing / demultiplexing device configured using the invention according to claim 3 (channel multiplexing circuit) and the invention according to claim 5 (channel multiplexing / demultiplexing device) will be described.

The encoded first channel data “a” and the encoded second channel data “b” are used to set the effective character n bits of the encoding used together to 1 byte,
Output every byte. In this effective character string, when synchronizing characters on the receiving side, for synchronization recognition,
A special character is inserted. As the special character to be inserted, the first special character 20 is assigned to the encoded first channel data a, and the encoded second channel data is assigned. b is assigned a second special character 21 different from the first special character 20.

The data of the two encoded channels is:
Byte multiplexed for each character byte (n bits)
The data c is character-multiplexed.

The receiving side receives the character multiplexed data c and detects the bit pattern of one or both of the two special characters by bit rotation or the like to synchronize the characters.

At this time, if special characters 20 and 21 corresponding to the respective channels are periodically inserted into the data a and b of the respective coded channels, character synchronization protection becomes possible. .

If they are not inserted periodically, n types of byte phases are monitored, and character synchronization is achieved with the phase at which the bit pattern of the special character is detected.

When character synchronization is performed and character bytes (n bits) are recognized, data a and b of the first and second channels are obtained by separating each byte.

Since the special characters inserted into the channel data a and b are synchronized with each other, the special characters can be easily detected and the channel can be recognized.

In order to detect one or both of the two special characters and synchronize the characters, the time slot in which the bytes constituting each channel on the character-multiplexed data c exist is known. The receiving side can also separate each byte after recognizing each of the two channels for each character byte.

In the present invention, when N channels (N is an integer of 3 or more) are provided, at least (N-1) special characters are detected or multiplexing at the transmission side is performed. It is necessary to recognize the order in advance, and recognize the time slots of all other channels from the time slots of the channel in which the special character is detected.

In FIG. 6, each channel is coded and then multiplexed. However, in the channel multiplexing / demultiplexing apparatus according to the second embodiment, m bits are parallelized before coding the data of each channel. It is also possible to perform encoding after byte multiplexing as one byte.

FIG. 7 shows a timing chart in this case. FIG. 7 schematically shows a case where two channels are multiplexed.

The data d of the first channel parallelized by m bits and the data e of the second channel parallelized by m bits are respectively the special character 20a before the first encoding and the second special character 20a. And the special character 21a before encoding is inserted.

The channel data is byte-multiplexed with m bits as 1 byte to become byte-multiplexed data f.

The bytes of the byte-multiplexed data f are independent for each channel, and the byte-multiplexed data f
Is encoded every m bits, it is stored that this character byte (n bits) is independent for each channel.

Accordingly, the data g obtained by encoding the byte-multiplexed data f is substantially the same as the character-multiplexed data c in FIG.

The receiving side receives the encoded data g, detects one or both of the bit patterns of the first and second special characters 20 and 21 by an operation such as bit rotation, and establishes character synchronization. , And decodes each character to obtain byte-multiplexed data f.

At this time, if each special character is periodically inserted into the data of each channel, character synchronization protection is possible.

If they are not inserted periodically, n types of byte phases are monitored (monitored), and character synchronization is achieved with the phase at which the bit pattern of the special character is detected.

The byte-multiplexed data f is obtained by byte-multiplexing the data of each channel with m bits as one byte. d and data e of the second channel parallelized by m bits are obtained.

The special characters before encoding inserted in the channel data d and e can be easily detected because of the byte synchronization, and thus the channel can be recognized.

In order to synchronize the character by detecting one or both of the two special characters, the time slot in which the byte of the character constituting each channel exists on the encoded data g is known. Since the time slot in which the byte of the character constituting each channel is present on the byte-multiplexed data f obtained by decoding this is also known, the receiving side sets two channels for each byte. It is also possible to separate bytes after recognition.

In the present invention, N channels (N is 3
In the case where (N is an integer greater than or equal to), at least (N
-1) It is necessary to detect the number of special characters or to know in advance the order of multiplexing on the transmission side, and to recognize the time slots of all other channels from the time slots of the channel where the special character is detected. is there.

In FIGS. 6 and 7, each channel is multiplexed for each character of the encoding method to be finally used. However, the channels are constructed by using the invention according to claim 4 and the invention according to claim 7. FIG. 8 shows a case where the channel multiplexing / demultiplexing apparatus uses a multiplexing method that does not perform multiplexing for each character, such as bit multiplexing, at the time of multiplexing. Here, a case where two channels are multiplexed is shown.

Encoded first channel data a
And the coded data b of the second channel are bit-multiplexed into bit-multiplexed data h.

On the receiving side, the bit-multiplexed data h is received, and the data a of the first channel, which is separated and encoded for each channel, and the data b of the second channel, which are encoded separately. obtain.

The bit pattern of a special character (consisting of 8 bits in the figure) inserted into the data of each channel is detected by an operation such as bit rotation to synchronize the characters, and at the same time, each bit is detected based on the special character. Recognize the channel.

In this case, assuming that there are N channels, a special character is detected for at least (N-1) channels, or the multiplexing order on the transmitting side is known in advance, and an arbitrary channel is determined. It is necessary to detect the special character inserted in the channel, recognize the channel, and recognize the time slots of all other channels from this time slot.

In the present invention, the assignment of special characters to each channel has been described as one special character per channel. However, one channel can be represented by a combination of a plurality of special characters.

For example, if four special characters A, B, C, and D are prepared and a combination of every two (pair) is obtained,
(AB), (AC), (AD), (BC),
(BD) and (CD), which can represent a total of six channels.

[0053]

Embodiments of the present invention will be described below with reference to the drawings.

[0054]

Embodiment 1 FIG. 1 is a block diagram showing a configuration of a channel multiplex transmission apparatus according to a first embodiment of the present invention.
FIG. 1 shows a case where three channels are multiplexed on the transmission side.

As a configuration of the channel multiplexing circuit 7 on the transmission side, data of each channel is output from the first to third channel data generators 1 to 3 and the corresponding coding circuit 4 is output.
~ 4 "to be encoded.

At this time, special characters peculiar to each channel are inserted like the encoded data a and b of the first and second channels shown in FIG.

The channel data generators 1 to 3 may be provided outside the channel multiplexing circuit 7.

Normally, the outputs of the encoding circuits 4 to 4 "are composed of n bits and are converted into n-bit parallel signals for each effective character or special character of a predetermined encoding method.

The outputs of the encoding circuits 4 to 4 ″ are input to a character multiplexing circuit 5 a, time-divisionally multiplexed and output as a 1-byte character composed of n bits, and input to a transmitter 6. The signal input to the transmitter 6 is usually a serial signal.

The output of the character multiplexing circuit 5a is
Is transmitted to the transmission path. The above is the configuration of the channel multiplexing circuit 7.

In the channel separation circuit 12 on the receiving side, after the transmitted signal is received by the receiver 8,
First, it is input to the character synchronizing circuit 9, and the character synchronizing circuit 9 detects a special character, thereby synchronizing the character and outputting the character for each character byte. This output is generally an n-bit parallel signal for each character.

The output of the character synchronizing circuit 9 is input to a character separating circuit 10a, and is separated and output for each character byte constituting three channels.

The three outputs of the character separation circuit 10a are respectively input to the corresponding channel recognition circuits 11 to 11 ″, and after the channel recognition is performed from the bit pattern of the special character inserted in the channel, the decoding circuit 14 ~ 14 ", the special character is terminated and output as channel data. The above is the configuration of the channel separation circuit 12.

[0064]

[Embodiment 2] FIG. 2 is a block diagram showing the configuration of a second embodiment of the present invention. FIG. 2 shows a case where three channels are multiplexed on the transmission side.

As a configuration of the channel multiplexing circuit 7 on the transmission side, the outputs of the first to third channel data generators 1 to 3 are input to a byte multiplexing circuit 5b, and the byte multiplexing circuit 5b converts each channel data into m bits in parallel. , This is taken as one byte and time-division multiplexed. The number m of bits of the parallel signal is the number of bits constituting one byte before encoding by the encoding method used.

The time-division multiplexed signal is input to the encoding circuit 4 and encoded. At that time, as shown in FIG. 7, a special character unique to each is inserted as in the case of the encoded data g.

The channel data generators 1 to 3 may be provided outside the channel multiplexing circuit 7.

The output of the coding circuit 4 is input to the transmitter 6 and sent out to the transmission path. The output of the encoding circuit 4 is preferably a serial signal. The above is the configuration of the channel multiplexing circuit 7.

In the channel separating circuit 12 on the receiving side, the receiver 8 receives the transmitted signal, the output of the receiver 8 is input to the character synchronizing circuit 9, and the character synchronizing circuit 9 detects a special character. In this way, character synchronization is achieved. The output of the character synchronization circuit 9 is normally an n-bit parallel signal for each byte of the character.

The n-bit parallel signal is input to the decoding circuit 14, decoded, and output as a decoded m-bit parallel signal.

Since the decoding circuit 14 needs to output a flag indicating that the special character has been decoded in the time slot obtained by decoding the special character, the decoding circuit 14 outputs 1 bit for the flag together with the m-bit parallel output. Output.

Since the m-bit parallel output is obtained by byte-multiplexing each channel with m bits as 1 byte, data of each channel can be obtained by separating bytes.

The output of the decoding circuit 14 is
b and is separated for each time slot of the m-bit parallel signal. At this time, the output for the flag is also separated for each time slot.

The separated m-bit parallel outputs are input to the corresponding channel recognition circuits 11 to 11 ″ to perform channel recognition. At this time, a flag indicating that a special character has been decoded and a timing are provided. Each channel is recognized from the bit pattern of the m-bit parallel signal in the matching time slot.

Since the m-bit parallel signal in the time slot at this time has no meaning as data, it is terminated by the terminating circuits 17 to 17 "after the channel recognition operation in the channel recognition circuits 11 to 11".

The m-bit parallel signals other than the time slots pass through the terminating circuits 17 to 17 "and are output from the channel separation circuit 12. The above is the configuration of the channel separation circuit 12.

In comparison with the first embodiment, in this embodiment, since the encoding circuit 4 in the channel multiplexing circuit 7 and the decoding circuit 14 in the channel separation circuit 12 can be shared by each channel, The scale can be reduced, which is particularly advantageous when multiplexing multiple channels.

Further, since the data of each channel is encoded after being multiplexed, the transmitted signal has an advantage that the encoding rule used is preserved.

Since the channel multiplexing circuit 7 and the channel separation circuit 12 shown in FIGS. 1 and 2 are compatible with each other, the channel multiplexing circuit 7 of FIG. 1 and the channel separation circuit 12 of FIG. And the configuration using the channel multiplexing circuit 7 in FIG. 2 and the channel separation circuit 12 in FIG. 1 are both effective.

[0080]

Third Embodiment FIG. 3 is a block diagram showing the configuration of a third embodiment of the present invention. FIG. 3 shows a case where three channels are multiplexed on the transmission side.

In the channel multiplexing circuit 7 on the transmission side,
The outputs of the channel data generators 1 to 3 are input to the corresponding encoding circuits 4 to 4 ″ and encoded, and the encoded data of the first and second channels shown in FIG. Special characters unique to each are inserted as in a and b.

Each output of the encoding circuits 4 to 4 ″ is input to a bit multiplexing circuit 5c, time-division multiplexed without character synchronization, and then transmitted from a transmitter 6 to a transmission line.

The channel data generators 1 to 3 may be provided outside the channel multiplexing circuit 7. The above is the configuration of the channel multiplexing circuit 7.

In the channel separating circuit 12 on the receiving side, the receiver 8 receives and outputs the signal from the transmission line, and separates the output in a manner corresponding to the multiplexing method of the bit multiplexing circuit 5c. Do.

The signals separated into the respective channels are input to the corresponding character synchronizing circuits 9 to 9 ″, respectively.
After character synchronization is achieved by detecting special characters in the character synchronization circuits 9 to 9 ", channel recognition is performed from the bit patterns of the special characters detected in the channel recognition circuits 11 to 11", and decoding is performed. The signal is decoded at 14 to 14 "and the end of the special character is received. The above is the configuration of the channel separation circuit 12.

[0086]

Embodiment 4 FIG. 4 shows the configuration of a fourth embodiment of the present invention. FIG. 4 is a block diagram showing a configuration of a channel demultiplexing circuit of the channel demultiplexing apparatus according to the present embodiment, and shows a case where three channels are multiplexed on the transmission side. The configuration of the channel multiplexing circuit 7 on the transmission side is as follows.
It is assumed that the configuration is as shown in FIG. 1 or FIG.

Referring to FIG. 4, in channel separation circuit 12 according to the present embodiment, receiver 8 receives a signal,
The character synchronizing circuit 9 detects a special character and performs character synchronization, and detects a special character for at least (n-1) (n is the total number of channels, n = 3 in the figure), and a channel recognition circuit. 11 is provided with information on a special character detected for each time slot constituting each channel.

The channel recognition circuit 11 uses the special character information given from the character synchronization circuit 9 to
Each channel is recognized, and information of a time slot in which a character byte constituting each channel exists is given to the character separating circuit 10a.

The character separation circuit 10a performs a separation operation for each time slot and requires a means for outputting which channel the separated signal belongs to.

Each output of the character separating circuit 10a is decoded by the corresponding decoding circuits 14 to 14 ".

If the order of multiplexing the channels in the channel multiplexing circuit 7 is known in advance in the channel separation circuit 12, the channel recognition circuit 11 extracts the special characters included in an arbitrary time slot detected by the character synchronization circuit 9. Then, the channels included in the time slots can be recognized, and the channels included in all the time slots can be recognized according to the multiplexing order.

[0092]

[Fifth Embodiment] FIG. 5 shows the configuration of a fifth embodiment of the present invention. FIG. 5 is a block diagram showing a configuration of a channel demultiplexing circuit of a channel demultiplexing apparatus according to a fifth embodiment of the present invention, and shows a case where three channels are multiplexed on the transmission side. It is assumed that the configuration of the channel multiplexing circuit 7 on the transmission side is the configuration shown in FIG. 1 or FIG.

Referring to FIG. 4, in channel separation circuit 12 according to the present embodiment, receiver 8 receives a signal,
The character synchronization circuit 9 detects a special character and performs character synchronization, and detects special characters in at least (n-1) channels (n is the total number of channels, n = 3 in the figure). Is provided with information on special characters detected for each time slot constituting each channel.

The channel recognizing circuit 11 recognizes each channel based on the information of the special character given from the character synchronizing circuit 9 and converts the information of the time slot where the character byte constituting each channel exists into the byte separating circuit 1.
0b.

The output of the character synchronizing circuit 9 is an n-bit parallel signal whose normal bit is n bits per character, and is output by the decoding circuit 14 as an m-bit parallel signal whose m bits are 1 byte. Separation circuit 1
0b.

If the delay in this decoding operation can be ignored, the channel recognition circuit 11 input to the byte separation circuit 10b
The information of the time slot in which the character byte forming each channel exists is the information of the time slot that is also effective in the decoded m-bit parallel signal.

The byte separating circuit 10b judges the byte of the m-bit parallel signal at the timing coincident with the information of the time slot in which the character byte forming each channel of the output of the channel recognition circuit 11 exists as the byte forming each channel. And output separately for each channel.

The output of the byte separating circuit 10b is input to the terminating circuits 17 to 17 "together with the flag output, and is output from the channel separating circuit 12 after terminating the data of the time slot after decoding the special character.

If the order of multiplexing the channels in the channel multiplexing circuit 7 is known in advance in the channel separation circuit 12, the channel recognition circuit 11 extracts the special characters included in an arbitrary time slot detected by the character synchronization circuit 9. Can recognize the channels included in the time slots, and can recognize the channels included in all the time slots according to the multiplexing order.

Although the embodiment of the present invention has shown the case where the number of all multiplexed channels is three, the present invention is also effective when the number of channels is four or more.

[0101]

As described above, the channel multiplexing / demultiplexing apparatus according to the present invention performs encoding for reducing low-frequency components of a multiplexed signal, and performs character synchronization at the time of decoding on the receiving side. In order to perform channel synchronization while performing character synchronization by changing the special character to be used for each channel, the bit rotation associated with synchronization is compared to a receiver that previously recognized the channel by performing frame synchronization separately from character synchronization. Since only one circuit is needed,
The circuit scale in the receiving / separating device is reduced to about 60%, and there is an effect that the device is reduced in size and power consumption is reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a channel multiplex transmission apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a channel multiplex transmission apparatus according to a second embodiment of the present invention.

FIG. 3 is a block diagram illustrating a configuration of a channel multiplex transmission apparatus according to a third embodiment of the present invention.

FIG. 4 is a block diagram illustrating a configuration of a channel multiplex transmission apparatus according to a fourth embodiment of the present invention.

FIG. 5 is a block diagram illustrating a configuration of a channel multiplex transmission apparatus according to a fifth embodiment of the present invention.

FIG. 6 is a timing chart showing an operation of the channel multiplex transmission device according to the first embodiment of the present invention.

FIG. 7 is a timing chart illustrating an operation of the channel multiplex transmission apparatus according to the second embodiment of the present invention.

FIG. 8 is a timing chart showing an operation of the channel multiplex transmission apparatus according to the third embodiment of the present invention.

FIG. 9 is a diagram showing a configuration of a conventional channel demultiplexing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st channel data generator 2 2nd channel data generator 3 3rd channel data generator 4 Encoding circuit 5a Character multiplexing circuit 5b Byte multiplexing circuit 5c Bit multiplexing circuit 6 Transmitter 7 Channel multiplexing circuit 8 Receiver 9 Character synchronization circuit 10a Character separation circuit 10b Byte separation circuit 10c Separation circuit 11 Channel recognition circuit 12 Channel separation circuit 14 Decoding circuit 17 Termination circuit 20 First special character 21 Second special character 20a Special before first encoding Character 21a Special character before second encoding a Encoded first channel data b Encoded second channel data c Character multiplexed data d m-bit parallel first channel Data e m bits parallelized second channel Data f byte-multiplexed data g encoded data h bit-multiplexed data 101 image signal 102 9B10B encoding circuit 103 frame signal 104 frame signal generator 105 10: 1 parallel-serial conversion circuit 106 4: 1 parallel-serial conversion Circuit 107 Transmitter 108 Transmitting device 109 Receiver 110 Serial-parallel conversion circuit 111 10B9B decoding circuit 112 Synchronization detection circuit 113 Channel selection circuit 114 Synchronization protection circuit 115 Hunting circuit 116 Receiving device

Claims (9)

[Claims] 1. A method for demultiplexing a plurality of channels, comprising: converting m bits to n bits (m, n) during channel multiplexing;
Is a predetermined integer, where m <n) encodes the channel using an encoding method of encoding, and assigns one or a plurality of channel recognition bytes, each having n bits, to each of the channels. Multiplexing the signal with the one or more channel recognition bytes inserted at a common interval, wherein the channel recognition byte is a code that is not used for normal output of encoding in the encoding method, A channel demultiplexing method, wherein the channel is recognized by detecting the channel recognition byte at the time of separation. 2. The transmission data of each channel is changed from m bits to n.
Means for encoding transmission data for each of the channels by using an encoding method for encoding bits (m and n are predetermined integers, where m <n); means for inserting one or a plurality of channel recognition bytes, which is one byte with n bits, into each of the channels at a common interval; means for multiplexing transmission data into which the channel recognition bytes have been inserted; Means for detecting a recognition byte and synchronizing characters for decoding; and means for recognizing and separating each channel from a channel recognition byte inserted in the character-synchronized reception signal, The channel recognition byte is a code that is not normally used for output in the above-mentioned encoding method, uniquely identifies the channel, and is one or more of which is also used for character synchronization. Channel demultiplexer, characterized in that a special character comprising a combination of. 3. The transmission data of each channel is changed from m bits to n.
Means for encoding transmission data for each of the channels by using an encoding method for encoding bits (m and n are predetermined integers, where m <n); means for inserting one or a plurality of channel recognition bytes, which is one byte with n bits, into each of the channels at a common interval;
The channel recognition byte is a code that is not normally used for output in the encoding method, uniquely identifies the channel, and is used for character synchronization. A channel multiplexing circuit characterized in that the channel multiplexing circuit is a special character composed of one or a plurality of combinations. 4. The transmission data of each channel is changed from m bits to n.
Means for encoding transmission data for each of the channels by using an encoding method for encoding bits (m and n are predetermined integers, where m <n); means for inserting one or a plurality of channel recognition bytes, which is 1 byte with n bits, into each of the channels at a common interval; and means for time-division multiplexing the transmission data with the channel recognition bytes inserted therein, The channel recognition byte is a code that is not normally used for output in the encoding method, and is a special character composed of one or a plurality of combinations for uniquely identifying the channel and also for character synchronization. And a channel multiplexing circuit. 5. A channel multiplexing / demultiplexing device, comprising: inputting transmission data from the channel multiplexing circuit according to claim 3; and transmitting data from the channel multiplexing circuit according to claim 3; A character synchronizing circuit that outputs an n-bit parallel signal for each character, a separating circuit that receives the n-bit parallel signal output of the character synchronizing circuit, and separates each channel that is time-division multiplexed as n-bit 1 byte, A channel recognition circuit that receives an output of the separation circuit and recognizes each channel from the inserted special character, and a decoding circuit that receives and decodes each output of the recognition circuit. Demultiplexer. 6. A channel separation multiplexing device, comprising: a channel multiplexing circuit according to claim 3; and transmission data from the channel multiplexing circuit according to claim 3, inputting the data and detecting the special character to synchronize the characters. A character synchronizing circuit that outputs an n-bit parallel signal for each character, a decoding circuit that inputs and decodes an n-bit parallel signal output of the character synchronizing circuit, and an m-bit 1 that receives an m-bit parallel signal output of the decoding circuit and A separation circuit that individually separates each channel time-division multiplexed as a byte, a channel recognition circuit that receives an output of the separation circuit, and recognizes each channel from the decoded special character, And a terminating circuit for receiving an output and terminating the decoded special character. apparatus. 7. A channel multiplexing / demultiplexing apparatus, comprising: a channel multiplexing circuit according to claim 4; and transmission data from the channel multiplexing circuit according to claim 4; A separating circuit for separating, inputting each output of the separating circuit, detecting a special character, and synchronizing a character; and inputting an output of the character synchronizing circuit, and detecting each of the special characters. A channel demultiplexing apparatus comprising: a channel recognition circuit that recognizes a channel; and a decoding circuit that receives and decodes each output of the channel separation circuit. 8. A channel multiplexing / demultiplexing device, comprising: inputting transmission data from the channel multiplexing circuit according to claim 3 and transmitting data from the channel multiplexing circuit according to claim 3; A character synchronizing circuit that outputs an n-bit parallel signal for each character; a channel recognition circuit that recognizes a time slot of a byte whose n bits constitute one byte from the detected special character; a separation circuit that receives n-bit parallel signal outputs and individually separates each channel that is time-division multiplexed based on the information of the channel recognition circuit, and a decoding circuit that receives and decodes each output of the separation circuit. A channel demultiplexing device comprising: 9. A channel multiplexing / demultiplexing device, comprising: inputting transmission data from the channel multiplexing circuit according to claim 3 and transmitting data from the channel multiplexing circuit according to claim 3; A character synchronizing circuit that outputs an n-bit parallel signal for each character; a channel recognition circuit that recognizes a time slot of a byte whose n bits constitute one byte from the detected special character; a decoding circuit for inputting and decoding an n-bit parallel signal output; and an m-bit parallel signal output for the decoding circuit, and individually separating the time-division byte-multiplexed channels based on information of the channel recognition circuit. A separating circuit, a terminating circuit that receives each output of the separating circuit and terminates the decoded special character, A channel multiplexing / demultiplexing device comprising: