JP3116427B2 - Modulation / demodulation device and automatic equalization method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modem and an automatic equalizing method therefor, and more particularly to a system in which a plurality of modems are arranged in a 1: N manner, or a fixed transmission line having a switching function. The present invention relates to a method for automatically equalizing a modem in a case.

[0002]

2. Description of the Related Art Conventionally, this type of modem is often used in the system shown in FIG. FIG. 3 is a block diagram showing a general system configuration example of this type of modulation / demodulation device. This figure shows a system in which a local station modem 102 installed on the host computer 101 side is connected to a plurality of partner modems 103 installed on the terminal device 104 side. When receiving the data from the partner modem 103, the local station modem 102 receives a control signal from the partner modem 103 before receiving data, such as a synchronization establishment signal, an address signal, a training signal, and a scramble signal. Then, synchronization establishment, equalizer adjustment, and scramble adjustment are performed as a sequence before data reception, and thereafter data is received. The equalizer adjustment corrects the phase characteristics of the transmission path and the like, and is adjusted by changing the setting of the equalizer in accordance with the training signal. This sequence is fixedly performed each time data is received.

[0003]

As described above, in the prior art, synchronization establishment, equalizer adjustment, and scramble adjustment are performed each time data is received, and this adjustment takes time. Chemistry adjustment takes the longest time. For this reason, the ratio of the time during which data is actually transmitted to the total time during which the transmission path is captured, that is, the data transmission efficiency is deteriorated. There is a problem that it gets worse.

[0004]

According to the present invention, there is provided a modem and an automatic equalizing method for the same in which the address information of the other station's modem and the own station's equalizer are equalized at the first reception of data with the other station's modem. And the equalizer setting information is read out from the address information at the time of receiving data again with the partner station modem, and the local station equalizer is automatically reset. .

[0005] Alternatively, first means for identifying whether data reception from the partner station modem is first or again based on an identification signal sent from the partner station modem, and the first means identifies the first. Second means for storing address information sent from the partner station modem at the time of data reception and equalizer setting information of the local station equalizer, and when the second means identifies again. When the data is received, the equalizer setting information attached to the address information stored by the second means is read based on the address information sent from the partner station modem, and the local station equalizer is automatically reset. This is a configuration including third means.

[0006] Further, the identification signal may be a signal transmitted from the partner station modem after detecting whether data transmission of the partner station modem is first or again after power-on.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a circuit configuration of the present embodiment. FIG. 4 shows a case where the host-side local-modem receiving apparatus 1 receives data from the terminal-side remote-modem transmitting apparatus 9 on the terminal side. As a signal for identifying whether data reception from the first station is first or again, the transmission of the power supply unit 13 is detected from the transmission / reception unit 9 of the partner station, and a signal identifying the first transmission or the second transmission after the reception is received. . FIG. 2 shows a configuration of a control signal that is received by the local station modem receiving section 1 prior to data reception from the partner station modem transmitting / receiving section 9.
(A) is a configuration diagram showing a case where the data reception is the first time, and (b) is a configuration diagram showing a case where the data reception is the second time.

First, the case where the data reception is first will be described. Since the power supply unit 13 is always turned on in the first case, the counter 15 detects that the power supply unit 13 is turned on, and when there is a data transmission signal from the interface unit 16, the counter 15 resets. Output the value. The control unit 14 receives this output, determines that this is the first transmission, adds an address signal from the address storage unit 11 and other signals, and sends the control signal shown in FIG. Output. Note that the signal of the output “reset” value of the counter unit 15 is called a state identification signal.
The encoder 12 encodes the control signal and outputs it to the modulator 10. The modulator 10 modulates the control signal into an analog signal and sends the analog signal to the transmission path.

In the local station modem receiving section 1, a control signal of an analog signal from the transmission line is received, demodulated and decoded by the demodulating section 8 and the encoder 3, and the detecting section 4 detects each signal. The control unit 5 receives the state identification signal from the detection unit 4 and determines that this is the first reception since this is a "reset" value. Automatically performed by the partner station training signal. At the same time, the address signal is stored in the storage unit 7.
After the adjustment of the equalizer 6, data is received. After the data reception is completed, the setting state of the automatic equalizer 6 is stored in the storage unit 6.

Next, in the case where the data is received again, in the transmitting / receiving unit 9 of the partner station, the power supply unit 13 is not turned on in this case, and only the transmission signal from the interface unit 16 is provided. Output the "set" value. The control unit 14 receives this output, determines that transmission is to be performed again, and sends out a control signal shown in FIG. In this case, no training signal is sent. In the own-station modulation / demodulation device receiving section 1, the control signal is received, and the control section 5 determines from the "set" value of the state identification signal that the reception is again. As a result, the equalizer setting information of this address stored in the storage unit 7 is read from the address signal, and the automatic equalizer 6 is automatically adjusted accordingly. This automatic adjustment takes much less time than the initial adjustment. After the data reception is completed, the equalizer setting state is read, and the setting information stored in the storage unit 7 is stored again. This is because the fine adjustment of the equalizer 6 is performed by the detection unit 4 during data reception.

[0011]

As described above, according to the present invention, the setting state of the equalizer is stored at the time of receiving the first data, and the automatic equalizer is set based on the stored setting information at the time of receiving the data again. The setting time of the equalizer can be shortened considerably. For this reason, there is an effect that the transmission efficiency of data transmission can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a circuit configuration of the present embodiment.

FIGS. 2A and 2B are diagrams showing a configuration of a control signal according to the present embodiment, wherein FIG. 2A is a configuration diagram when data is received first, and FIG.

FIG. 3 is a block diagram showing a general system configuration example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Local-station modulation / demodulation device receiving part 2, 16 interface part 3, 12 Encoding part 4 Detecting part 5, 14 Control part 6 Automatic equalizer 7 Storage part 8 Demodulation part 9 Counterpart station modulation / demodulation device transmission part 10 Modulation part 11 Address storage Unit 13 Power supply unit 15 Counter unit

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04B 3/04-3/18 H04B 7/005 H04L 27/01

Claims (2)

(57) [Claims] 1. A stores the equalizer setting information in the first address information and the local station equalizer before Symbol counterpart station modem during data reception with the partner station modem, and the other station modem in the time of re-receiving data of automatic equalization side of modem for automatically resetting the own station equalizer reads the equalizer setting information from the address information, the phase
Whether the data reception from the hand-station modem is first or again
Identified by identification signal sent from partner station modem
A first means for performing the operation, and when the first means identifies the first time,
Received from the other station's modem when receiving
Address information and equalizer setting information of the local station equalizer are stored.
When the first means identifies again
Received from the other station's modem when receiving
The address stored by the second means according to the address information.
Reads the equalizer setting information attached to the dress information
A third means for automatically resetting the station equalizer . Wherein said identification signal modulation and demodulation according to claim 1, wherein said at the other station modem that data transmission of the other station modem detects sent or power-on after the first or again apparatus.