JPH0936828A - Waveform fractioning and shaping method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform a time division transmission for plural digital signals which are different in transmission rate on the same transmission medium by receiving a digital signal, dividing high speed data and low speed data and eliminating the noise contained in high speed data. SOLUTION: This device is provided with a reception output signal conversion part 1 receiving the digital signal on a transmission medium and converting the signal into a reception output signal and a low speed data fractioning part 5 fractioning the reception output signal which is identified by a low speed data identification part 4 and is except low speed data and low speed data from the reception output signal stored in a reception output signal storage part 3 and outputting them. Further, the device is provided with a high speed data identification part 6 identifying high speed data and noise from the reception output signal except low speed data and a high speed data output part 7 outputting high speed data that the noise identified by the high speed data identification part 6 is eliminated from the reception output signal except low speed data. Thus, plural kinds of digital signals are fractioned and the noise contained in high speed data can be eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waveform classification and shaping method and apparatus, and more particularly to a waveform classification and shaping method and apparatus in a digital transmission system for time-divisionally transmitting a plurality of types of digital signals having different transmission rates.

[0002]

2. Description of the Related Art In conventional time division multiplex transmission, digital information is time division multiplexed at the same transmission rate and transmitted on one medium. Further, when transmitting digital information at different transmission rates, the transmission medium corresponding to each transmission rate is used for transmission. For example, the transmission speed is 64 kbps and 32 k
When there is a digital signal of bps, since the transmission speed is different, the digital signal of 64 kbps is transmitted using the transmission medium A and the digital signal of 32 kbps is transmitted using the transmission medium B, respectively.

[0003]

However, in the conventional time division multiplex transmission, when transmission is performed at different transmission rates, it is not possible to transmit on one medium, so that different transmission media are used for each transmission rate. Need to use.

Further, when the noise superimposed on the transmission medium overlaps the data sampling point due to the influence of external noise or the like and the influence of the reflection of the transmission waveform at the time of multipoint connection,
Misreading may occur and a data error may occur. Further, when transmitting a high-speed digital signal, the amplitude and width of the waveform are reduced due to transmission loss, and the data cannot be read correctly, so that the transmission distance is limited.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a waveform classification and shaping method and apparatus capable of time-divisionally transmitting a plurality of digital signals having different transmission rates on the same transmission medium. For general purposes. Also,
An object of the present invention is to provide a waveform classification and shaping method and apparatus capable of removing noise superimposed on a transmission medium during transmission and suppressing the occurrence of a data error.

A further object of the present invention is to provide a waveform classification and shaping method and apparatus which can correct narrowing of the pulse width of high-speed data due to transmission loss, reduce reception errors, and extend the transmission distance. is there.

[0007]

FIG. 1 is a diagram for explaining the principle of the present invention. A first aspect of the invention is a waveform classification and shaping method in a digital transmission system in which digital signals having different transmission rates are time-divisionally transmitted on the same transmission medium, and the digital signal is received (step 1), and high-speed data and low-speed data are divided. (Step 2), noise included in the high speed data is removed (Step 3).

In a second aspect of the invention, in the first aspect of the invention, when dividing data and removing noise, a digital signal on a transmission medium is received, converted into a reception output signal of a logical level, and received. Generates a clock that is faster than the output signal, reads the received output signal with the clock, and temporarily stores it. The pulse width of the stored received output signal is the slowest of the multiple types of digital signals. Compared with the pulse width that can be determined as a signal, when the pulse width is larger than the pulse width, it is identified as low-speed data, and the received output signal and the low-speed data obtained by removing the low-speed data from the accumulated received output signal are separately output, The pulse width of the received output signal excluding the low-speed data is compared with the pulse width that can be determined as a signal with a high transmission speed among a plurality of digital signals, and a pulse width larger than the pulse width Sometimes it identifies high-speed data, when the pulse duration less than the pulse width, identified as noise,
The reception output signal excluding the identified noise is output from the reception output signal excluding the low-speed data.

A third aspect of the present invention is a waveform classification and shaping method in a digital transmission system in which digital signals having different transmission speeds are time-divisionally transmitted on the same transmission medium, in which high-speed data due to transmission loss during transmission on the transmission medium is transmitted. Corrects narrow pulse width. A fourth aspect of the invention is to detect the changing point of the rising or falling edge of the pulse from the output high speed data when correcting the narrowing of the pulse width in the third aspect of the invention, and use the detected changing point as a reference. A specified pulse width is generated, a read timing clock of the pulse width generated based on the detected change point is generated, the pulse width is read by the read timing clock, and output as shaped high-speed data.

According to a fifth aspect of the invention, in a waveform classification and shaping device in a digital transmission system for time-divisionally transmitting digital signals having different transmission rates on the same transmission medium, a digital signal is received and high-speed data and low-speed data are divided. , And has a sorting and shaping means for removing noise included in high-speed data.

In a sixth aspect of the present invention, the classification and shaping means in the fifth aspect of the present invention receives the digital signal on the transmission medium and converts it into a reception output signal of a logical level, and a reception output signal. A clock generating means for generating a higher speed clock, a received output signal accumulating means for reading a received output signal with the clock from the clock generating means, and temporarily accumulating the received output signal, and a received output signal accumulating means. The pulse width of the received output signal is compared with a pulse width that can be determined as a signal having a slow transmission speed among a plurality of types of digital signals, and when the pulse width is larger than the pulse width, low speed data is identified and low speed data is identified. And the reception output signal stored in the reception output signal accumulating means, except the low speed data identified by the low speed data identifying means. Compares the pulse width of the received output signal excluding the low-speed data with the low-speed data classification means that separates the output signal and the low-speed data and outputs, and the pulse width that can be determined as the signal with the highest transmission speed among multiple types of digital signals. However, when the pulse width is larger than the pulse width, it is identified as high-speed data, and when the pulse width is smaller than the pulse width, high-speed data identification means for identifying noise and high-speed data identification from the received output signal excluding the low-speed data. It has a high-speed data output means for outputting the reception output signal excluding the noise identified by the means.

According to a seventh aspect of the invention, in a waveform classification and shaping device in a digital transmission system for time-divisionally transmitting digital signals having different transmission rates on the same transmission medium, correction of narrow pulse width of high-speed data due to transmission loss during transmission. It further has a correction means to do.

According to an eighth aspect of the invention, the above-mentioned correction means is
Detection means for detecting a rising or falling transition point of the pulse from the output of the high-speed data output means, and pulse width generation means for generating a prescribed pulse width based on the transition point of the pulse detected by the detection means A clock generating means for generating a read timing clock of the output of the pulse width generating means with reference to the change point of the pulse detected by the detecting means; and a reading for generating the pulse width generated by the pulse width generating means by the clock generating means. A data output means for reading with a timing clock and outputting as shaped high-speed data is included.

As described above, according to the present invention, in the digital transmission system in which a plurality of types of digital signals having different transmission rates are time-divisionally transmitted on the same transmission medium, the digital signal on the transmission medium is received and the received output signal is received. Converted to, generate a clock faster than the received output signal, read the received output signal with the clock from the clock generation means, temporarily store the received output signal, and store the accumulated received output signal. Compare the pulse width with the pulse width that can be determined as low-speed data among multiple types of digital signals,
When the pulse width is larger than the pulse width, it is identified as low speed data. Therefore, the reception output signal obtained by removing the low-speed data from the accumulated reception output signal and the low-speed data are separately output. In addition, the pulse width of the received output signal excluding low-speed data is compared with the pulse width that can be determined as high-speed data among multiple types of digital signals, and when the pulse width is larger than the pulse width, it is identified as high-speed data and the pulse When the pulse width is smaller than the width, it is identified as noise. It also outputs the reception output signal from which noise has been removed from the reception output signal from which low-speed data has been removed.

Thus, it is possible to separate a plurality of types of digital signals and remove noise contained in high-speed data. Furthermore, according to the present invention, the rising and falling transition points of a pulse are detected from high-speed data excluding noise, a prescribed pulse width is generated with the transition point of the pulse as a reference, and the transition point of the pulse is determined. A timing clock for reading the pulse width as a reference is generated, the pulse width is read, and output as shaped high-speed data. This makes it possible to correct narrowing of the pulse width of high-speed data due to transmission loss and reduce reception errors.

[0016]

FIG. 2 shows the system configuration of the present invention. The waveform classification and shaping device classifies a digital signal into high-speed data and low-speed data, and has a function of removing noise from the classified high-speed data, and a pulse width narrowing correction of the classified high-speed data. , A waveform shaping device 200 that shapes a waveform. The configuration of the waveform classification device 100 is shown in FIG. 3, and the configuration of the waveform generation device 200 is shown in FIG.

FIG. 3 shows the configuration of the waveform classification device of the present invention. The waveform classification device shown in the figure includes a reception output signal conversion unit 1 that receives a digital signal on a transmission medium and converts it into a reception output signal, a clock generation unit 2 that generates a clock faster than the reception output signal, and a reception output. Signal to clock generator 2
A received output signal accumulating section 3 for reading and temporarily accumulating with a clock from the low speed data discriminating section 4 for discriminating low speed data from the received output signal accumulated in the received output signal accumulating section 3,
From the received output signal accumulated in the received output signal accumulating unit 3, the low speed data discriminating unit 5 for discriminating the received output signal and the low speed data from which the low speed data discriminated by the low speed data discriminating unit 4 is output, and the low speed data are excluded. A high-speed data discriminating section 6 for discriminating high-speed data and noise from a received output signal, and a high-speed data output section 7 for outputting high-speed data from which noise discriminated by the high-speed data discriminating section 6 has been removed To be done.

A second configuration of the present invention is the addition of the function of performing waveform shaping to the first configuration described above, and corrects the narrowing of the pulse width of the separated high-speed data. FIG. 4 shows the configuration of the waveform shaping device of the present invention. The waveform shaping device shown in FIG. 1 has a pulse width generation unit 9 that generates a prescribed pulse width based on a rising or falling transition point of a pulse from high-speed data, and a change in pulse detected by a transition point detection unit 8. It is composed of a clock generation unit 10 that generates a data read timing clock based on points, and a data output unit 11 that outputs the output of the pulse width generation unit 9 as read shaping high-speed data with the read timing clock generated by the clock generation unit 10. It

[0019]

Embodiments of the present invention will be described below. [First Embodiment] First, as a first embodiment, time-division transmission is performed on the same transmission medium, two types of digital signals of high speed and low speed having different transmission speeds are separated, and noise included in high speed data is removed. The operation of the waveform classification device 100 to be removed will be described.

A digital signal from a medium in which two types of digital signals having different transmission rates are transmitted is input from a digital signal input terminal 20. The input digital signal is received output signal converter 1
Is converted into a logic level reception output signal.

The clock generator 2 generates a clock faster than the received output signal, the pulse width of the received output signal is read by the generated clock, and the pulse width of the received output signal is temporarily received. Output signal storage unit 3
Is accumulated in The low-speed data identification unit 4 compares the pulse width of the received output signal stored in the received output signal storage unit 3 with the pulse width X.

FIG. 5 is a diagram for explaining the operation of the low speed data classification unit according to the embodiment of the present invention. In the figure,
(A) is a pulse width X, which is an integer multiple of the clock pulse width generated by the clock generation unit 2 and is larger than a predetermined (ideal) pulse width of high-speed data, and low-speed data processing (ideal). Indicates the pulse width within the range that does not exceed the pulse width of. (B) shows the pulse width of the reception output signal. When the pulse width of the received output signal is larger than the pulse width X by γ, it is identified as low speed data. In the example of the same figure, since the pulse width of the received output signal is larger than the pulse width X, the data shown in FIG.

In the low-speed data classification unit 5, the low-speed data classified by the low-speed data classification unit 4 is divided into the low-speed data classified by the low-speed data classification unit 4 from the low-speed data classified by the low-speed data classification unit 4. It is output from the output terminal 21. The high-speed data identification unit 6 compares the pulse width of the received output signal from which the low-speed data has been removed with the pulse width Y.

FIG. 6 is a diagram for explaining a high speed data identifying unit according to an embodiment of the present invention. In the figure, (A)
The pulse width Y of is larger than the pulse width of noise to be removed with a pulse width that is an integral multiple of the clock width generated by the clock generation unit 2, and indicates a pulse width in a range that does not exceed the predetermined pulse width of high-speed data. (B) is the pulse width after the low speed data is removed. In the example of the same figure, since the pulse width of the reception output signal from which the low-speed data has been removed is smaller than the pulse width Y, the data shown in (B) is identified as noise.

The high-speed data output unit 7 outputs high-speed data from which the noise identified by the high-speed data identifying unit 6 has been removed from the reception output signal from which the low-speed data has been removed. In the above embodiment, two types of data, high speed data and low speed data, are targeted. However, the present invention is not limited to this example, and by setting a predetermined pulse width arbitrarily, there are n types of data. It is possible to separate.

That is, even in the digital transmission system in which a plurality of digital signals having different speeds are time-divisionally transmitted on the same transmission medium, the waveforms of the present invention are selected by sequentially selecting the digital signals from the low speed side and comparing the pulse widths. The multi-stage classification and shaping function enables waveform classification and shaping of a plurality of digital signals.

Therefore, according to this embodiment, a plurality of types of digital signals having different transmission rates can be time-divisionally transmitted on the same transmission medium, and noise of high-speed data having a predetermined pulse width or more can be removed. It is possible. [Second Embodiment] Next, the operation of the waveform shaping device will be described as a second embodiment of the present invention.

In this embodiment, an operation for correcting narrowing of the pulse width of high speed data due to transmission loss will be described. The change point detection unit 8 receives the high speed data from the high speed data input terminal 22 and detects the change point of the high speed data.

The pulse width generation unit 9 generates a specified pulse width of high-speed data with reference to the pulse change point detected by the change point detection unit 8. The clock generation unit 10 generates a read timing clock of the output of the pulse width generation unit 9 with reference to the pulse change point detected by the change point detection unit 8.

The output shaped by the pulse width generation unit 9 is read by the data output unit 11 according to the reading timing clock and is output to the shaped high speed data output terminal 24 as shaped high speed data. FIG. 7 shows time-division transmission images of two kinds of digital signals having different transmission rates according to the present invention. In the figure, a high speed data digital signal with a transmission speed of 1.5 Mbps and a low speed data digital signal with a transmission speed of 64 kbps are time-divisionally transmitted on the same medium.

The high speed data is time t1 to t2, time t3.
.About.t4 and times t5 to t6 are transmitted on the same transmission medium, and low-speed data is transmitted at times t2 to t3 and times t4 to t5. In addition,
The present invention is not limited to the above embodiments, and various modifications and applications are possible within the scope of the claims.

[0032]

As described above, according to the waveform classification and shaping method and apparatus of the present invention, in the digital transmission system for time-divisionally transmitting a plurality of types of digital signals having different transmission rates on the same transmission medium, a plurality of types can be used. The noise included in the high speed data can be removed by separating the digital signal of.

Further, it is possible to reduce the reception error by the waveform shaping for correcting the narrowing of the pulse width of the high speed data due to the transmission loss.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the principle of the present invention.

FIG. 2 is a system configuration diagram of the present invention.

FIG. 3 is a configuration diagram of a waveform classification device of the present invention.

FIG. 4 is a configuration diagram of a waveform shaping device of the present invention.

FIG. 5 is a diagram for explaining an operation of a low speed data classification unit according to an embodiment of the present invention.

FIG. 6 is a diagram illustrating a high-speed data identification unit according to an embodiment of the present invention.

FIG. 7 is a diagram showing a time division transmission image of two types of digital signals having different transmission rates according to the present invention.

[Explanation of symbols]

 1 reception output signal conversion unit 2 clock generation unit 3 reception output signal storage unit 4 low speed data identification unit 5 low speed data classification unit 6 high speed data identification unit 7 high speed data output unit 8 change point detection unit 9 pulse width generation unit 10 clock generation unit 11 data output unit 20 digital signal input terminal 21 low speed data output terminal 22 high speed data output terminal 24 shaping high speed data output terminal 100 waveform sorting device 200 waveform shaping device 300 waveform sorting and shaping device

Claims (8)

[Claims] 1. A waveform classification and shaping method in a digital transmission system in which digital signals having different transmission rates are time-divisionally transmitted on the same transmission medium, wherein the digital signal is received, and high-speed data and low-speed data are divided on a receiving side. A waveform classification and shaping method, characterized in that noise included in the high-speed data is removed. 2. A digital signal on the transmission medium is received, converted into a reception output signal of a logical level, a clock faster than the reception output signal is generated, and the reception output signal is read by the clock, The pulse width of the received output signal that has been temporarily stored is compared with a pulse width that can be determined to be a signal with a slow transmission speed among a plurality of types of digital signals, and a pulse width of a pulse width larger than the pulse width is compared. When discriminating from low-speed data, the received output signal obtained by removing the low-speed data from the accumulated reception output signal and the low-speed data are separately output, and the pulse width of the reception output signal excluding the low-speed data is Of the plurality of digital signals, a pulse width that can be determined to be a signal having a high transmission speed is compared, and when the pulse width is larger than the pulse width, high speed data is identified, When the pulse duration less than the scan width is identified as noise, waveform separation shaping method according to claim 1, wherein outputting the received output signal except for the noise identified from the received output signal excluding the low-speed data. 3. A waveform classification and shaping method in a digital transmission system in which digital signals having different transmission rates are time-divisionally transmitted on the same transmission medium, wherein a pulse width of the high-speed data is narrowed due to transmission loss during transmission on the transmission medium. The method according to claim 1, further comprising: 4. A rising or falling transition point of a pulse is detected from the output high speed data, a prescribed pulse width is generated with the detected transition point as a reference, and the detected transition point is used as a reference. The waveform according to claim 3, wherein a read timing clock of the generated pulse width is generated, the pulse width is read by the read timing clock, and output as shaped high-speed data to correct pulse width narrowing of high-speed data due to transmission loss. Sorting method. 5. A waveform classification and shaping device in a digital transmission system for time-divisionally transmitting digital signals having different transmission speeds on the same transmission medium, wherein high-speed data and low-speed data are divided on the receiving side and included in the high-speed data. A waveform classification / shaping device having a classification / shaping means for removing noise. 6. The classification and shaping means receives a digital signal on the transmission medium and converts it into a reception output signal of a logic level, and a reception output signal converting means for generating a clock faster than the reception output signal. Clock generation means, reception output signal storage means for reading the reception output signal with the clock from the clock generation means, and temporarily storing the reception output signal, and reception output signal stored in the reception output signal storage means Of the plurality of types of digital signals is compared with a pulse width that can be determined to be a signal having a slow transmission rate, and low-speed data for identifying low-speed data and low-speed data for identifying a low-speed data when the pulse width is larger than the pulse width. Identifying means, and removing the low-speed data identified by the low-speed data identifying means from the received output signal accumulated in the received output signal accumulating means. A low-speed data discriminating means for discriminating and outputting the reception output signal and the low-speed data, and a pulse width of the reception output signal excluding the low-speed data is determined to be a signal having a high transmission rate among the plurality of types of digital signals. A high-speed data identifying means for identifying a pulse width larger than the pulse width as high-speed data and a pulse width smaller than the pulse width for identifying noise as compared with the possible pulse width, and a reception excluding the low-speed data. The waveform classification and shaping device according to claim 5, further comprising: a high-speed data output unit that outputs a reception output signal in which the noise identified by the high-speed data identification unit is removed from the output signal. 7. A waveform classification and shaping device in a digital transmission system for time-divisionally transmitting digital signals having different transmission speeds on the same transmission medium, in a correction means for correcting narrowing of the pulse width of the high-speed data due to transmission loss during transmission. The waveform classification and shaping device according to claim 5, further comprising: 8. The correction means includes a detection means for detecting a change point of rising or falling of a pulse from an output of the high-speed data output means, and a change point of the pulse detected by the detecting means as a reference. Pulse width generating means for generating a prescribed pulse width; clock generating means for generating a read timing clock of the output of the pulse width generating means on the basis of the change point of the pulse detected by the detecting means; 8. The waveform classification and shaping device according to claim 7, further comprising data output means for reading the pulse width generated by the generation means with the read timing clock generated by the clock generation means and outputting it as shaped high-speed data.