JPH10322401A - Eye pattern measurement device and its method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To observe an eye pattern and to measure channel quality quantitatively by synthesizing channel quality information calculated based on an eye pattern signal with an eye pattern signal and displaying the synthesized signal. SOLUTION: An eye pattern analysis section 2 calculates channel quality information from an eye pattern signal outputted from a modem section 1. An eye pattern channel quality information synthesis section 3 receives the eye pattern signal received from the modem section 1 and the channel quality information received from the eye pattern analysis section 2, and in the case that only the eye pattern signal is received by the section 3, the section 3 divides equally a unit time for drawing one point into two, assigns the first half of the unit time to drawing of the eye pattern signal and the last half to drawing of the channel quality information. Then the section 3 outputs the synthesized eye pattern signal and the channel quality information to an eye pattern display device 4, which draws the eye pattern signal and the channel quality information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an eye pattern measuring apparatus and method.

[0002]

2. Description of the Related Art JP-A-57-33856 and JP-A-6-32673.
In the technique described in Japanese Patent Application Laid-Open No. 5 (1993) -1995, since only an eye pattern display device such as an oscilloscope can observe an eye pattern, a means other than the eye pattern display device is used as a means for confirming quantitative line quality. Thus, an eye pattern display device such as an oscilloscope can observe an eye pattern, but cannot quantitatively measure line quality.

The present invention has been made in view of the above-described problems, and has as its object to provide an eye pattern measurement apparatus and method capable of performing eye pattern observation and quantitative measurement of channel quality. I have.

[0004]

According to an aspect of the present invention, there is provided a modem unit for demodulating a carrier signal input from a line and outputting an eye pattern signal. An eye pattern analysis unit that calculates line quality information indicating a line quality based on a signal; and an eye pattern line quality information combining unit that combines the line quality information and the eye pattern signal and outputs the combined signal to a display unit. Is adopted.

Further, as means relating to the above-mentioned eye pattern measuring apparatus, means for employing an oscilloscope as a display means is employed.

As means relating to an eye pattern measuring method, line quality information indicating line quality is extracted from an eye pattern signal obtained by demodulating a carrier signal input from a line, and the line quality information is converted into an eye pattern signal. Means of displaying on the same screen as character information along with the based eye pattern is adopted.

As means relating to the above-mentioned eye pattern measuring method, means for displaying line quality information together with an eye pattern on an oscilloscope is employed.

[0008]

In the above means, since the eye pattern signal is synthesized with the character information by the eye pattern line quality information synthesizing section and outputted to the eye pattern display device, the eye pattern can be observed based on the eye pattern signal. In addition, the line quality can be quantitatively confirmed based on the character information.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an eye pattern measuring apparatus and method according to the present invention will be described below with reference to the drawings.

[1] Description of Configuration First, the functional configuration of the present embodiment will be described with reference to the block diagram shown in FIG. Referring to FIG. 1, a modem unit 1 includes an A / D conversion circuit, a demodulation circuit, and the like, demodulates a carrier signal input from a line to extract an eye pattern signal, and converts the eye pattern signal into an eye pattern analysis unit 2 Output to the eye pattern line quality information synthesizing unit 3.

The eye pattern analysis unit 2 calculates line quality information from the eye pattern signal output from the modem unit 1 and outputs the line quality information to the eye pattern line quality information combining unit 3. Here, the eye pattern analysis unit 2 calculates phase jitter, gain hit, dropout, S / N, and the like from the eye pattern signal as line quality information, and uses the result of the calculation as character information as the eye pattern line quality information synthesis unit. Output to 3.

The eye pattern line quality information synthesizing section 3 synthesizes the eye pattern signal output from the modem section 1 and the line quality information output from the eye pattern analysis section 2 and outputs the synthesized signal to the eye pattern display device 4. I do. The eye pattern display device 4 displays the eye pattern and the line quality information on the same screen based on the eye pattern signal and the line quality information input from the eye pattern line quality information combining unit 3.

[2] Description of Operation Next, the operation of the eye pattern measuring apparatus having the above configuration will be described with reference to a timing chart shown in FIG. This timing chart shows the timing of signals in the eye pattern line quality information combining unit 3.

As described above, the eye pattern signal input from the modem unit 1 and the line quality information (character information) input from the eye pattern analysis unit 2 are used by the eye pattern As shown in the figure, usually, when only the eye pattern signal is input, the unit time for drawing one point on the eye pattern display device 4 is equally divided, and the first half of the unit time is allocated to the drawing for the eye pattern signal. And the latter half are assigned to drawing for the line quality information (character information).

The eye pattern line quality information synthesizing section 3 outputs the eye pattern signal thus synthesized and the line quality information (character information) to the eye pattern display device 4, and outputs the eye pattern and the line quality information. (Character information). FIG. 3 is a diagram showing an example of the drawing, in which the line quality information is drawn as character information.

The time allocation in combining the eye pattern signal and the channel quality information (character information) is not limited to the above case (equally divided). That is, it is conceivable to determine the distribution according to the data amount of both the eye pattern signal and the line quality information (character information).

[0017]

As described above, the eye pattern measuring apparatus and method according to the present invention have the following effects. (1) Since the line quality information is simultaneously displayed as character information together with the eye pattern, it is possible to quantitatively measure the line quality while observing the eye pattern. (2) Since the line quality information is displayed on the oscilloscope together with the eye pattern, the line quality can be measured by effectively using the oscilloscope which is an existing measuring instrument.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a functional configuration of an embodiment of an eye pattern measuring apparatus and method according to the present invention.

FIG. 2 is a timing chart illustrating an operation of an eye pattern measuring apparatus and method according to an embodiment of the present invention.

FIG. 3 is a plan view showing a display example of an eye pattern measuring apparatus and method according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Modem part 2 ... Eye pattern analysis part 3 ... Eye pattern line quality information synthesis part 4 ... Eye pattern display device

Continued on front page (72) Inventor Hiroyuki Tamura 5-7-1 Shiba, Minato-ku, Tokyo Inside NEC Corporation

Claims (4)

[Claims] 1. A modem unit (1) for demodulating a carrier signal input from a line and outputting an eye pattern signal, and an eye pattern analysis unit for calculating line quality information indicating line quality based on the eye pattern signal. (2) an eye pattern line quality information synthesizing unit (3) for synthesizing the line quality information and the eye pattern signal and outputting the synthesized signal to a display means (4). . 2. An eye pattern measuring apparatus according to claim 1, wherein said display means is an oscilloscope. 3. Line quality information indicating line quality is extracted from an eye pattern signal obtained by demodulating a carrier signal input from the line, and the line quality information is converted into character information together with an eye pattern based on the eye pattern signal. An eye pattern measuring method characterized by displaying on the same screen. 4. The eye pattern measurement method according to claim 3, wherein the line quality information is displayed on an oscilloscope together with the eye pattern.