JPS63156437A - Method and device for control of per-emphasis in data transmission system - Google Patents

Abstract

PURPOSE:To simplify a training processing, by deciding whether a pre-emphasis data transmitted from a transmission side equipment is an optimum value or not at a reception side equipment, and performing the generation and setting of the optimum value by applying the handshake of re-training. CONSTITUTION:The setting of a compromise equalizer is performed at the transmission part 5 of the transmission side equipment 1, and the pre-emphasis data (PE1) is generated at the part. A generated preemphasis data of a data signal 20 is fetched in the third register 13 of the reception side equipment 2. Next, the compromise equalizer 12 loads the data PE1, and a decision part 15 decides whether it is the optimum value or not. When it is not the optimum value, the optimum value is generated by the compromise equalizer 12, and it is transferred to the transmission part 5 of the same reception side equipment 2 through the decision circuit 15.

Description

[Detailed Description of the Invention] [Summary] In a data transmission system, pre-emphasis and role-playing in training operations between transmitting and receiving devices are performed by handshaking during retraining between the transmitting device and the receiving device. I made it. This eliminates the need for a large amount of data processing such as extraction of tap coefficients, and simplifies the operating procedure and hardware configuration.

[Industrial Application Field] The present invention relates to a pre-emphasis control method and apparatus for a data transmission system.

[Conventional technology]

When data is transmitted from one device (sending device) to the other device 71 (receiving device) through a line, the line functions as a filter, and the transmitted signal may deteriorate. In the past, this filter deterioration was generally corrected within the modem of the receiving device, but the level of the transmitted signal was emphasized in advance in the transmitting device, and when the receiving device received it, it was corrected within the modem of the receiving device. Ensure that the signal level is flat across the band. So-called pre-emphasis may be performed. A conventional example of such a pre-emphasis control system is shown in FIG. 4, for example.

This sends O! to the sending device l and this sending device 1. a3
In a data transmission system having such a configuration, an example is shown in which a pre-emphasis device f1 section 4 is provided in the modem of the transmitting side device 1 in a data transmission system configured with a receiving side device 2 connected via a data transmitting side device 1. When transmitting, first, as a first step, a flat signal is sent from the transmitting equipment 211 to the receiving equipment 212. On the other hand, in the receiving side device 2, as a second stage operation, the sending signal is pulled in by an automatic equalizer, and then the receiving unit 212
In the third stage, the tap coefficients of the equalizer are extracted. Then, as the fourth step, the receiving side equipment 71
Tap coefficient data is transferred from 2 to transmitting equipment 2!11. In the transmitting side device 1, as a fifth stage operation, the amount of pre-emphasis etc. is set based on the transferred data. Then, as a sixth stage operation, data is transmitted from the transmitting device 1 to the receiving device 2 under normal conditions.

[Problem that the invention seeks to solve]

However, in such a conventional bias control method, a huge amount of information must be handled in the third stage operation, which is the extraction of tap coefficients, and the fourth stage operation [1] When reversely transferring tap coefficient data, command information indicating that tap coefficient data is to be sent must be sent.

Furthermore, it was necessary to install a fixed equalizer in the transmitting section in order to set the pre-emphasis on the transmitting device l, which is the operation in step 5 [1]. In view of these JG patterns, the conventional pre-emphasis control method has the disadvantage of complicating the hardware configuration of the device and complicating the processing operations.

The present invention has been made in view of these conventional problems, and its purpose is to provide a pre-emphasis control that allows initial determination of the 1/4 constant equalizer of the transmitter/receiver section by a more in-depth operation procedure. An object of the present invention is to provide a method and apparatus.

[Means for solving problems]

In order to achieve the above object, the present invention provides a pre-emphasis function section in both the transmitting section 5 and the receiving section 6 of the "transmitting/receiving" devices 1 and 2 constituting the data transmission system as shown in FIG. Equipment: Sends a pre-emphasis signal (a kind of test signal, phase 8 to the flat signal) from the transmitting side device 1 onto the line 3 during the training operation between the 111t and the receiving side device 2'i2. On the other hand, the receiving device 2 determines the pre-emphasis signal I) η, and if pre-emphasis is necessary, transfers the rrr training request signal to the transmitting device l. The device can be initialized.

[Effect]

In the training operation, an information area for pre-emphasis is provided in the training signal and is sent onto the line 3. On the other hand, the sending device 1 has a data holding means such as a register in its sending section, and stores the pre-emphasis data sent to the line 3. Then, when the receiving side device 2 receives the pre-emphasis data and detects filter deterioration on the line, it determines the optimum value and installs the corresponding receiving equipment; 12 sends a retraining request to the transmitting device 2!11, which causes the transmitting device l
Then, the optimum value for pre-emphasis is determined, and regular data transmission is then performed.

〔Example〕

FIGS. 2 and 3 are diagrams showing an embodiment of the present invention.

The second is the transmitting/receiving section, i! 1 shows an example of the internal configuration of the transmitting section 5 and receiving section 6 of the modem il and 2. The transmitter 5 performs equalization processing for pre-emphasis.
The compromize equalizer 7, which is the L stage, the fixed equalizer 8, and the compromize equalizer 7 and I2
．． When the equalizer control g8 unit 9 that controls the I7 equalizer 8 and the transmitting/receiving device operate as the transmitting side device 1! 1j3-A first register lO that temporarily stores the pre-emphasis signal data sent to the receiving device 2, and stores the optimum value data for retraining handshake during the pre-emphasis operation when operating as the receiving side device 2: 52 The compromise equalizer 7 and both registers 10 and 11 are connected to the four wire 3 via a signal line 17 for transmission.

The receiving unit 6 is connected to the line 3 via a receiving signal line 18 and includes a second combromize equalizer 13 that creates optimal value data for 1L pre-emphasis, and a transmitter when operating as a receiving side device 2112. A third register 13 receives and stores pre-emphasis data sent from the device 711, and a fourth register receives and stores optimal value data transferred from the receiving device when operating as the sending device 1. 14, a determination circuit 15 that checks the received pre-emphasis signal data and determines whether it can be used as an optimum value in the system;
The training unit 16 generates a signal requesting training based on the determination result in (pi).

The operation during training in a modem equipped with the transmitting/receiving section 5.6 having such a configuration will be explained.

First, when it is desired to send data from the transmitting equipment 7'LL to the receiving equipment 2112, the transmitting equipment 711 creates a data signal consisting of a training signal 21 and a processed data signal 22, as shown in FIG. In the modem according to this embodiment,
A data signal storage area 21b for pre-emphasis is provided after the rate sequence storage section 21a which is the 1'ff element of the training signal 21, and data for pre-emphasis can be set in this storage area 21b.

First, in the first stage, a compromise equalizer is set in the transmitter 5 of the transmitter equipment 711, and pre-emphasis data (referred to as PE 1) is created here. This data PEI is a provisional optimum value created in the transmitter 5, and is set in the storage area 21b of the data signal 20, while being stored and held in the first register IO. When the data signal 20 created in this way reaches the receiving unit 6 of the receiving device 2, which is the other station, the pre-emphasis data is taken into the third register 13 of the receiving device 2. The combromizing equalizer 12 of the device 2 loads the data PEI, and the determination unit 15 checks whether this is the optimum value for the system. If this is the optimum value, the above training is considered to have been successful and no new operation is performed, and the training is completed and processing data transmission operation begins.

On the other hand, when the data loaded from the third register 13 is not the optimum value, the combromized fist equalizer 12 creates the optimum value f1, and the second register 11 of
Transfer to. On the other hand, a command signal is output from the 1 determination section 15 to the retraining section 16, and the retraining section 16
outputs a signal requesting retraining. This retraining output is sent to the second register 11 through the fixed equalizer 8 and equalizer control section 9 in the transmitting section 5, and is sent to the four-wire 31- to the transmitting side device l. As a result, the shaking hand operation of 11.1 training is performed between the transmitting side device 1 and the receiving side device 2. At this time, the optimum value data stored in the second register 11 is transferred to the fourth register 14 of the transmitting device 1 by a shake hand operation.
is input to. The optimum value data once stored in the fourth register 14 is transferred to the equalizer control unit 9 in the transmitting unit 5 of the transmitting device l, and is further input to the compromise equalizer 7. Then, pre-emphasis optimum value data is written into the first register lO by the compromise equalizer 7, and the first register 10 in which data PEI was stored in the first stage is updated with the optimum value data, and the equalizer Initial settings are performed.

In this way, since the pre-emphasis handshake is performed in a retraining operation, there is no need to include a special pre-emphasis processing sequence during the initial operation of data transmission, and there is no need to extract a large number of tap coefficients. The bits required for data processing due to the provision of the compromise equalizer 7 are 7 bits for the pre-emphasis reception cycle, 4 bits for the compromise equalizer setting information of the own station transmitter 5, and 4 bits for the compromise equalizer setting information of the remote station transmitter 5.
4 for compromise/equalizer setting request information.
A total of 16 bits is sufficient, including one bit for indicating whether pre-emphasis is to be performed or not.

〔Effect of the invention〕

As explained above, according to the present invention, the receiving device determines whether or not the pre-emphasis data sent from the transmitting device is the optimal value, and the optimal value is determined by the retraining handshake. By creating and setting the training process, the training process can be simplified.
Furthermore, it is possible to simplify the hardware configuration.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the principle of the present invention, and FIG. 21A is a blow diagram showing the configuration of the transmitter/receiver section of a modem to which Unreleased II is applied.
FIG. 3 is a diagram showing the configuration of a data signal created when implementing the present invention, and FIG. 4 is a schematic configuration diagram of a data transmission system employing conventional pre-emphasis control. 1... Sending side device 2... Receiving side device 3... Line 4... Pre-emphasis function section 5... Transmitting section 6... Receiving section 7.12... Combromize O equalizer 8. ... Fixed equalizer 9 ... Equalizer control section 10 ... First register 11 ... Second register 13 ... Third register 14 ... Fourth register 15 ... Judgment Department

Claims (1)

[Claims] 1) In a training operation between a transmitting device (1) and a receiving device (2) of a data transmission system, data for pre-emphasis is sent from the transmitting device to the receiving device. On the other hand, the steps include: retaining the data within the own station; determining whether the pre-emphasis data is the optimal value for the system in the receiving device; and retraining if the determination result is not the optimal value. A step of transmitting a request signal to a transmitting device and transmitting an optimal value in the system through a retraining handshake, and a step of transmitting pre-emphasis data held in the transmitting unit in the transmitting device that has received the optimal value. A pre-emphasis control method in a data transmission system comprising: updating the equalizer and initializing the equalizer; 2) A compromise equalizer (7) for creating data for pre-emphasis, which is provided in the transmitting section (5) of the transmitter/receiver device (1), (2) for data transmission; a first register (10) for temporarily storing data; a second register (11) for temporarily storing an optimal pre-emphasis value during reception operation; an equalizer control section (9) for controlling the compromise equalizer; A third register (13) for temporarily storing pre-emphasis data output from the transmitting device is provided in the receiving section (6) of the transmitting/receiving device for transmission, and a third register (13) for temporarily storing pre-emphasis data output from the transmitting device is provided. a compromising equalizer (12) that creates a pre-emphasis optimum value based on a negative determination result in the determining unit (15); A pre-emphasis system in a data transmission system consisting of a re-training unit (16) that requests re-training based on the determination result, and a fourth register (14) that temporarily stores the optimal pre-emphasis value from the receiving device during transmission operation. Control device.