JP2734796B2 - Scalar network analyzer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a scalar network
The present invention relates to an analyzer, and particularly to a scalar network analyzer for measuring a frequency characteristic of a device under test.

[0002]

2. Description of the Related Art A conventional scalar network analyzer includes a sweep oscillator for outputting a sweep signal and a frequency from a start frequency f1 to a stop frequency f2 set in advance by an operator as a frequency signal that changes in response to the sweep signal. A detector that receives the output of the device under test whose frequency signal is connected to the input side, and outputs a signal proportional to the output level from the device under test, A vertical amplifier that outputs a signal and a frequency setting signal that indicates a start frequency and a stop frequency output by the sweep oscillator described above are input and converted into character signals corresponding to the start frequency f1 and the stop frequency f2, respectively. A character output circuit for outputting, and a horizontal for amplifying the above-mentioned sweep signal and outputting it as a horizontal signal Width device, the horizontal signal, the vertical signal, and the character signal described above are input, a specific point is used as a base, and a distance proportional to the horizontal signal is used in the horizontal direction from the base and in the vertical direction from the base. It has a display unit for displaying a point image at a point having a distance proportional to the above-described vertical direction signal, and displays a character corresponding to f1 outputted by the character signal on a vertical line passing through the point image corresponding to the above-mentioned start frequency f1. The display includes a display for displaying a character corresponding to the stop frequency f2 for outputting the above-described character signal on a vertical line passing through the above-described point image corresponding to the stop frequency f2.

Next, a conventional scalar network analyzer will be described in detail with reference to the drawings.

FIG. 5 is a block diagram showing an example of a conventional scalar network analyzer, and FIG. 6 is an explanatory diagram showing a state of an image displayed on the display shown in FIG.

A sweep signal is supplied from a sweep oscillator 101 to a horizontal amplifier 105 and a start frequency f.
The frequency signal that outputs a frequency from 1 to the stop frequency f2 corresponding to the output level of the sweep signal is
Added to 2. For example, when the device under test 102 is a frequency converter, the sweep oscillator 101
Is converted into another frequency by the device under test 102 and output.

When the output signal from the device under test 102 is input to the detector 103, the detector 103 converts the input signal into a signal proportional to the input level, and
4 is output. The vertical amplifier 104 amplifies the level of the input signal at a predetermined ratio and applies the amplified signal to the vertical signal input unit of the display 206 as a vertical signal. The horizontal amplifier 105 amplifies the sweep signal at a predetermined ratio and applies the amplified signal as a horizontal signal to a horizontal signal input unit of the display 206.

A frequency setting signal representing a start frequency f1 and a stop frequency f2 is applied from a sweep oscillator 101 to a character output circuit 207. The character output circuit 207 outputs the input frequency setting signal to the start frequency f.
The values are converted into character values representing 1 and a stop frequency f2, respectively, and output as a character signal. On the display unit of the display 206, a distance proportional to the level of the horizontal signal input in the horizontal direction based on a predetermined base point and a distance proportional to the level of the input vertical signal are used as described above. A point image is displayed at a point vertically away from the base point. Therefore, apparently, the point image is a continuous curve, and the horizontal axis represents the frequency axis and the vertical axis represents the output level of the device under test.

The display unit 206 displays a character, that is, a frequency corresponding to a character signal input corresponding to the start frequency f1 below the point image on a vertical line passing through the point image corresponding to the start frequency f1. Display and also
A character corresponding to the stop frequency f2 in the above-described character signal is displayed below the point image on a vertical line passing through the point image corresponding to the stop frequency f2 among the point images described above.

[0009]

In the conventional scalar network analyzer described above, the display 206 is displayed on the display 206 together with a curve indicating the frequency characteristic of the device under test, which measures the start frequency f1 and the stop frequency f2 output from the sweep oscillator. A device that outputs a frequency different from the frequency applied from the sweep oscillator to the device under test, such as the frequency converter already described, and displays the output characteristics of this device on the display of this scalar network analyzer. When displayed on the upper side, there is a disadvantage that the frequency output from the measured object cannot be confirmed on the display.

[0010] An object of the present invention is to display the upper and lower frequency values of the output frequency on a display even when measuring the output of a device under test that outputs a frequency different from the frequency output by the sweep oscillator. An object of the present invention is to provide a scalar network analyzer which can be displayed together with a curve indicating an output characteristic of a device under test.

[0011]

A scalar network analyzer according to a first aspect of the present invention is a sweep oscillator for outputting a sweep signal and a frequency signal having a frequency from a start frequency f1 to a stop frequency f2 corresponding to the sweep signal. A detector for receiving the output of the device under test to which the frequency signal is input, and outputting a detection signal proportional to the input level; a vertical amplifier for amplifying the detection signal and outputting the signal as a vertical signal; The output of the measuring object is input, and the start frequency f1 and the stop frequency f2 are measured at the time when the sweep oscillator outputs the frequency of the signal output by the fixed object, and the measured values are output as f3 and f4, respectively. And the output of the counter, f3 and f4, to character signals corresponding to f3 and f4, respectively. A character output circuit for converting and outputting the signal, a horizontal amplifier for amplifying and outputting the sweep signal, a horizontal signal input for the output of the horizontal amplifier, a vertical signal input for the vertical signal, and a screen for inputting the character signal. A display that displays a point image at a position that has a distance in the horizontal direction from the specific point above and that is proportional to the level of the horizontal signal input and that has a distance in the vertical direction that is proportional to the level of the vertical signal input. And displaying a character corresponding to f3 in the character signal on a vertical line passing through the point image corresponding to the start frequency f1 output by the sweep oscillator, and displaying the point image corresponding to the stop frequency f2. And a display having a character display unit for displaying a character corresponding to f4 in the character signal on a vertical line passing through the display.

A scalar network analyzer according to a second aspect of the present invention includes a sweep oscillator for outputting a sweep signal and a frequency signal having a frequency from a start frequency f1 to a stop frequency f2 in response to the sweep signal; A detector that receives an output of a device under test that receives a signal as an input and outputs a detection signal proportional to the input level, a vertical amplifier that amplifies the detection signal and outputs the signal as a vertical signal, and an output of the device under test. A counter that inputs the start frequency f1 and the stop frequency f2, measures the frequency of the signal output by the target constant at the time when the sweep oscillator outputs, and outputs the measured values as f3 and f4, respectively; F3 which is the output of the counter
And a first character output circuit for converting and outputting the character signals corresponding to f3 and f4, respectively, and the start frequency f1 output from the sweep oscillator.
And a frequency setting signal indicating the stop frequency f2 from the sweep oscillator, converting the sweep signal into character signals corresponding to the start frequency f1 and the stop frequency f2, respectively, and outputting the sweep signal. A horizontal amplifier for amplifying and outputting a signal; a horizontal signal input for the output of the horizontal amplifier, a vertical signal input for the vertical signal, and an output of the first and second character signal output circuits as inputs and a specific point on the screen. A display unit that displays a point image at a position having a distance proportional to the level of the horizontal signal input in the horizontal direction and a distance proportional to the level of the vertical signal input in the vertical direction from the specific point. F1 of the character signal is plotted on a vertical line passing through the point image corresponding to the start frequency f1 output by the sweep oscillator.
The characters corresponding to f2 and f3 in the character signal are placed in this order or on the vertical line passing through the point image corresponding to the stop frequency f2, respectively. And a display device having a character display section for displaying the characters in a reverse order.

[0013]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a scalar network analyzer according to the present invention, and FIG. 2 is an explanatory diagram showing a state of display by the display of FIG.

The scalar network analyzer according to the present embodiment differs from the conventional scalar network analyzer described with reference to FIG. 5 in the following points.

That is, in the conventional scalar network analyzer of this type shown in FIG. 5, the frequency setting signal output from the sweep oscillator 101 is output to the character output circuit 207, whereas In the scalar network analyzer of the present invention shown in FIG.
The counter 108 receives the output of the device under test 102 as an input and outputs the start frequency f1 described above to the sweep oscillator 10.
1 is output as a frequency signal, the frequency f3 output from the device under test is measured, and the frequency f4 output from the device under test 102 at the time the sweep oscillator 101 outputs the stop frequency f2 is measured. The character output circuit 107 measures and outputs the measured values to a character output circuit 107. The character output circuit 107 converts the measured value into a character signal corresponding to the input measured value and outputs the character signal to the display 106.

The display 106 is the display 20 described with reference to FIG.
6 is displayed except that the character display of the frequency f3 is displayed at the character display position of the start frequency f1 displayed by the character 6 and the character display of the frequency f4 is displayed at the position where the display 206 displays the character of the stop frequency f2. The same operation as that of the unit 206 is performed.

The components described above among the components shown in FIG. 1, that is, components other than the counter 108, the character output circuit 107, and the display 106 are already shown in FIG.
Since the same operation as described above is performed, the description is omitted.

FIG. 3 is a block diagram showing another embodiment of the present invention, and FIG. 4 is an explanatory diagram for explaining a display state of the display 306 shown in FIG.

In FIG. 3, the counter 108 is the same as the counter 108 shown in FIG. 1. Similarly, the first character output circuit 117 is similar to the character output circuit 107 shown in FIG.
Is the same as Also, the second character output circuit 127
Is the same as the character output circuit 207 described in FIG.

Since the components shown in FIG. 3 except for the components already described and the display 306 are the same as the components described with reference to FIG. Only the operation described above will be described, and description of other components will be omitted.

The display 306 is the display 10 described with reference to FIG.
6 has a vertical signal input portion and a horizontal signal input portion similar to those of FIG. 6, and the output characteristics from the DUT are displayed in the same manner as the display device 106 displays the output characteristics from the signals input to these input portions. It has an input section for a character signal output from the output circuit 117 and the second character output circuit 127, and is based on a character signal corresponding to the start frequency f1 among the character signals output from the second character output circuit 127. The lower part on a vertical line passing through a point image displaying the output of the device under test corresponding to the frequency f3 output from the device under test 102 at the time when the frequency signal having the character start frequency f1 is input to the device under test 102 To be displayed. Similarly, when a frequency signal having a stop frequency f2 is input to the device under test 102, the point image is displayed on a vertical line passing through a point image displaying the output of the device under test corresponding to the frequency f4 output by the device under test 102. A character corresponding to the frequency f4 described above is displayed below the character signal output from the first character output circuit 117.

The display 306 displays a character based on the character signal corresponding to the start frequency f1 in the character signal output from the second character output circuit 127 below the character displayed at the frequency f3. . further,
A character based on a character signal corresponding to the stop frequency f2 is displayed below the character indicating the frequency f4 on the display 306 and the frequency.

Accordingly, the display unit 306 displays a curve indicating the output characteristic of the device under test, and the characters of the start frequency f1 and the stop frequency f2 output by the sweep oscillator 101 are displayed in characters. When the start frequency f1 and the stop frequency f2 are applied from the sweep oscillator 101 to the device under test 102, the frequencies f3 and f4 output from the device under test 102 are displayed in association with a curve indicating the output characteristics of the device under test. Will be done.

[0025]

As described above, the scalar of the present invention
By using a network analyzer, even if the device under test converts the frequency of the input signal to another frequency and outputs it, such as a frequency converter, the maximum And the lowest frequency can be confirmed by displaying it on the display.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a scalar network analyzer of the present invention.

FIG. 2 is an explanatory diagram for explaining a display state of a display device shown in FIG. 1;

FIG. 3 is a block diagram showing another embodiment of the present invention.

FIG. 4 is an explanatory diagram for explaining a display state of a display device shown in FIG. 3;

FIG. 5 is a block diagram showing an example of this type of conventional scalar network analyzer.

FIG. 6 is an explanatory diagram illustrating a display state of a display device in FIG. 5;

[Explanation of symbols]

 Reference Signs List 101 Sweep oscillator 103 Detector 104 Vertical amplifier 105 Horizontal amplifier 106 Display 107 Character output circuit 108 Counter 117 First character output circuit 127 Second character output circuit 306 Display

Claims (2)

(57) [Claims] 1. A sweep oscillator for outputting a sweep signal and a frequency signal having a frequency from a start frequency f1 to a stop frequency f2 corresponding to the sweep signal, and an output of a device under test to which the frequency signal is input. A detector that outputs a detection signal proportional to the input level, a vertical amplifier that amplifies the detection signal and outputs the signal as a vertical signal, and an output of the device under test that receives the start frequency f
A counter for measuring the frequency of the signal output by the target constant at the time when the sweep oscillator outputs 1 and the stop frequency f2, and outputting the measured values as f3 and f4, respectively, and an output of the counter. a character output circuit that converts f3 and f4 into character signals corresponding to f3 and f4, respectively, outputs a character signal, a horizontal amplifier that amplifies and outputs the sweep signal, and outputs the vertical signal from the horizontal amplifier as a horizontal signal input. A direction signal is a vertical signal input, and the character signal is an input, and a distance from a specific point on the screen is proportional to the level of the horizontal signal input in a horizontal direction, and the vertical signal input is in a vertical direction from the specific point. A start frequency output by the sweep oscillator, having a display unit for displaying a point image at a position having a distance proportional to the level; A character corresponding to f3 in the character signal is displayed on a vertical line passing through the point image corresponding to 1 and a character corresponding to f4 in the character signal is displayed on a vertical line passing through the point image corresponding to the stop frequency f2. A scalar network analyzer comprising: a display having a character display unit for displaying characters. 2. A sweep oscillator that outputs a sweep signal and a frequency signal having a frequency from a start frequency f1 to a stop frequency f2 corresponding to the sweep signal, and an output of a device under test that receives the frequency signal as an input. A detector that outputs a detection signal proportional to the input level, a vertical amplifier that amplifies the detection signal and outputs the signal as a vertical signal, and an output of the device under test that receives the start frequency f
A counter for measuring the frequency of the signal output by the target constant at the time when the sweep oscillator outputs 1 and the stop frequency f2, and outputting the measured values as f3 and f4, respectively, and an output of the counter. a first character output circuit for converting f3 and f4 into character signals corresponding to f3 and f4, respectively, and a frequency setting signal indicating the start frequency f1 and stop frequency f2 output from the sweep oscillator. A second character output circuit which receives from the sweep oscillator, converts and outputs a character signal corresponding to a start frequency f1 and a stop frequency f2, respectively, a horizontal amplifier which amplifies and outputs the sweep signal, The output of the amplifier is a horizontal signal input, the vertical signal is a vertical signal input, and the first and second signals are A distance which is proportional to the level of the horizontal signal input from the specific point on the screen and which is proportional to the level of the vertical signal input from the specific point. And a character corresponding to f1 and f3 in the character signal on a vertical line passing through the point image corresponding to the start frequency f1 output by the sweep oscillator. Characters corresponding to f2 and f4 in the character signal are displayed vertically on a vertical line passing through the point image corresponding to the stop frequency f2 in the order or reverse order, respectively. A scalar network analyzer comprising: a display having a character display unit.