JPH01251811A - Transversal equalizer - Google Patents

Abstract

PURPOSE:To simplify the constitution of a transversal equalizer together with reduction of its cost by connecting selectively a single computing element to one or more units of transversal filters and D/A converting circuits. CONSTITUTION:Plural transversal filters 1, D/A converting circuits 2 and interfaces 4 are prepared together with a single computing element 3 and a single interface 5. Then the interface 5 is selectively connected to plural interfaces 4. In such a constitution, the filters 1, the circuits 2 can be connected to and separated from the element 3 respectively. This optional connection is secured only at the change of the distortion characteristics of an equalizer and a tap coefficient is set. This connection, however, is not usually secured. This just a single computing element suffices to plural equalizers. As a result, the constitution of a transversal equalizer is simplified together with reduction of its cost.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a transversal equalizer, and more particularly to a transversal equalizer having a plurality of equalizers and having a compact and easy-to-implement configuration.

[Prior Art] Conventionally, a transversal type equalizer, as shown in FIG. A digital-to-analog conversion circuit (D
/A conversion circuit) 2, and an arithmetic unit 3 that performs calculations based on the distortion characteristics of the filter 1 and outputs a digital control signal to the D/A conversion circuit 2.

[Problem to be solved by the invention]

The conventional equalizer described above includes a transversal filter 1
．． Since the D/A converter 2 and the arithmetic unit 3 are integrated, when configuring a plurality of transversal type equalizers, the transversal type equalizer 1 .
D/A converter 2. There is a problem that the corresponding number of computing units 3 and 3 are required, and the structure becomes complicated.

Furthermore, once the -degree Tabb coefficient is set, no arithmetic unit is required until the next change, but with this conventional equalizer, it is necessary to always have an arithmetic unit for each filter, and the equalizer There is also the problem of high prices.

SUMMARY OF THE INVENTION An object of the present invention is to provide a transversal equalizer that has a simpler structure and lower cost by reducing the number of arithmetic units.

[Means to solve the problem]

The transversal type equalizer of the present invention directly connects one or more transversal filters and a D/A conversion circuit that outputs a tap coefficient control signal to the transversal filter, and the D/A conversion circuit And this D/A
The arithmetic unit that outputs digital control signals to the conversion circuit is connected to the converter circuit so as to be separable via an interface.

[Effect]

In the above configuration, one arithmetic unit is selectively connected to one or more transversal filters and D/A conversion circuits to set tap coefficients, and normally, they are separated to configure an equalizer. do.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention.

In the figure, ■ is a transversal filter, 2 is a D/
In the A conversion circuit, 3 is an arithmetic unit. The transversal filter 1 has a plurality of weighting circuits, and the weighting controls the signal input to the input terminal IN to have desired distortion characteristics using a tap coefficient control signal made of an analog voltage supplied to the circuit. Output from output terminal ○UT. The D/A conversion circuit 2 converts the digital control signal output from the arithmetic unit 3 into an analog signal and converts it into a transversal filter. The calculation unit 3 calculates the tap coefficients of the transversal filter 1 that provide the required distortion characteristics, and sends the digital control signal obtained from the tap coefficients to the D/A conversion circuit 2.

Here, the transversal filter 1 and the D/A conversion circuit 2 are directly connected, but the D/A conversion circuit 2 and the arithmetic unit 3 are configured to be connected via interfaces 4 and 5, respectively. ing. In this embodiment, transversal filter 1. While a plurality of D/A conversion circuits 2 and interfaces 4 are provided, only one arithmetic unit 3 and one interface 5 are provided, and the interface 5 is configured so that it can be selectively connected to the plurality of interfaces 4. There is.

Therefore, according to this configuration, each transversal filter 1 and D/A conversion circuit 2 and the arithmetic unit 3 can be arbitrarily connected and separated by 9, and both are connected only when changing the distortion characteristics of the equalizer. The tap coefficients can be set using the following steps, and the two can normally be kept separate. As a result, only one arithmetic unit is required for a plurality of equalizers, and the configuration can be simplified and the cost can be reduced.

〔Effect of the invention〕

As explained above, the present invention is configured so that one arithmetic unit can be selectively connected to one or more transversal filters and D/A conversion circuits, so that when the two are connected, By setting the coefficients, the equalizer can be configured in a separate state, which allows only one arithmetic unit to be used for multiple equalizers, simplifying the configuration and reducing costs. .

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional structure. 1... Transversal filter, 2... D/Ai
tA circuit, 3... Arithmetic unit, 4.5... Interface.

Claims (1)

[Claims] 1, comprising one or more transversal filters, a digital-to-analog conversion circuit for outputting a tap coefficient control signal to the transversal filter, and an arithmetic unit for outputting a digital control signal to the digital-to-analog conversion circuit; 1. A transversal equalizer, characterized in that a transversal filter and a digital/analog conversion circuit are directly connected, while the digital/analog conversion circuit and an arithmetic unit are separably connected via an interface.