JP2001230736A - Reception state display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reception state display device for more easily finding the best point of the direction of a reception antenna for simultaneously receiving radio waves from two earth satellites. SOLUTION: Corresponding to read set contents, a power supply voltage is set so as to supply the reception signals of specified polarized waves from the reception antenna (S210-S240), the signal level LV1 of a specified channel is read for the satellite A (S250-S270) and then, the signal level LV2 of the specified channel is similarly read for the satellite B (S28O-S300). Based on both signal levels LV1 and LV2, a value for which the difference of both signal levels is subtracted from the added value of both signal levels is obtained as a display level LVD (=|LV1+LV2|-|LV1-LV2|) (S310) and it is displayed on a display device 17 together with the previously read set contents (S320). By adjusting the reception antenna to the direction where the display level LVD becomes a peak, the radio waves from both satellites A and B are excellently received.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reception state display device for detecting and displaying a reception state of a reception antenna for receiving radio waves from two adjacent artificial satellites.

[0002]

2. Description of the Related Art Conventionally, two artificial satellites (for example, JCS) that provide broadcasting services and the like using orthogonally polarized waves are used.
AT3 (ParfecTV) and JCSAT4 (Sky) etc.)
There is known a so-called two-beam receiving antenna which receives a radio wave from a satellite with one reflector and selectively outputs a reception signal for any polarization from any artificial satellite.

[0003] With this two-beam receiving antenna, in order to receive both radio waves from both satellites well,
It is necessary to adjust the direction (elevation angle and azimuth angle) of the receiving antenna. As a device suitable for such adjustment of the direction of the receiving antenna, the applicant of the present application has already successively received and continuously received radio waves from both artificial satellites, and received the received levels simultaneously by two bar graphs. There has been proposed a receiving state display device for displaying (refer to Japanese Patent Application Laid-Open No. H11-308182).

With this device, the direction of the receiving antenna may be adjusted by comparing two bar graphs so that the reception levels of radio waves from both satellites become equal.
Unlike the conventional reception status display device, which can only display the reception level from one of the satellites, there is no need to switch the display when comparing the reception levels of both satellites. It can be significantly improved.

[0005]

However, the above-described apparatus for displaying two reception levels simultaneously has the following problems. That is, the direction of the receiving antenna at which the reception levels of the radio waves from both artificial satellites are equal is not always the best, and even if the reception level is the same, it may be the noise level, and the display is performed. Because it is necessary to determine whether the received signal level is based on noise or a signal received by radio waves from artificial satellites.
It takes extra effort.

In order to solve the above problems, the present invention more easily finds the best point of the direction of the receiving antenna when adjusting the direction of the receiving antenna for simultaneously receiving radio waves from two artificial satellites. It is an object of the present invention to provide a reception state display device capable of performing the above.

[0007]

According to a first aspect of the present invention, a satellite selection signal generated by a selection signal generation means is supplied to a reception antenna. From the antenna, for two artificial satellites that receive radio waves simultaneously by the receiving antenna, received signals of radio waves from both artificial satellites are alternately output according to the satellite selection signal.

[0008] From the received signal output by the receiving antenna, a channel selecting means extracts a signal of a preset designated channel, and a level detecting means detects a signal level of the extracted signal. Then, based on the signal levels (also referred to as reception levels) of the two satellites detected by the level detection means, the display level calculation means subtracts the difference between the two signal levels from the sum of the two signal levels to thereby change the display level. The calculated display level is displayed by the display means as the reception state of the received signal.

That is, assuming that the reception levels of radio waves from both satellites are LV1 and LV2, the display level LVD can be expressed by the following equation (1), and the sum of reception levels of both satellites | LV1 + LV2 | Is larger, and the smaller the difference | LV1-LV2 | between the reception levels between the two artificial satellites, the larger the display level LVD.

LVD = | LV1 + LV2 |-| LV1-LV2 | (1) For example, both reception levels LV1 and LV2 are noise levels (for example, 60 dBμ) each having a magnitude based on noise.
When both reception levels LV1 and LV2 are both signal levels (for example, 8
0 dBμ), the display levels LVD are 120 dBμ, 160 dBμ, and 120 dBμ, respectively, when comparing the case where one reception level LV1 is a signal level and the other reception level LV2 is a noise level.

That is, the magnitude of the display level LVD is clearly different between the case where both the reception levels LV1 and LV2 are the same signal level (in the case of) and the case in which the other reception levels LV1 and LV2 are the same (in the case of). Will appear. Although the unit of dBμ is used here, it may be simply expressed by a numerical value indicating the level.

Instead of using the equation (1), the equation (1a) in which the sum of the two signal levels is multiplied by M and the difference between the two signal levels is multiplied by N is used, or the equation (1b) in which each is squared is used. May be used to calculate the display level LVD. LVD = M | LV1 + LV2 | -N | LV1-LV2 | (1a) LVD = | LV1 + LV2 | ^2- | LV1-LV2 | ² (1b) In this case, the sensitivity of the display level LVD can be further increased.

Therefore, according to the reception status display device of the present invention, the direction of the reception antenna may be adjusted so that the display level displayed on the display means is maximized, and the displayed level is based on the reception signal. Since it is not necessary to judge whether or not the adjustment is performed, the labor of the adjustment work can be further reduced, and the workability of the adjustment work can be improved.

The designated channel extracted by the channel selecting means may be fixedly set, or may be arbitrarily set by the user. By the way, when the radio wave from the artificial satellite received by the receiving antenna is composed of two orthogonal polarizations, not only the direction of the receiving antenna but also the converter so that the receiving state of both polarizations is optimized at each receiving antenna. It is necessary to adjust the tilt.

Therefore, when the radio wave is composed of two orthogonal polarizations, the selection signal generation means not only generates the satellite selection signal but also generates the polarization in accordance with an external designation. It is desirable to also generate a polarization selection signal for specifying a wave, and to be able to display a reception state for an arbitrary polarization.

In this case, the tilt adjustment of the converter can be performed together with the azimuth adjustment of the receiving antenna, so that the workability of the adjustment work can be further improved.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a book that receives a received signal from a receiving antenna 2 that receives orthogonally polarized radio waves transmitted from two artificial satellites (hereinafter, referred to as satellites A and B) and displays the reception state. 1 is a block diagram illustrating a configuration of an entire reception state detection device 10 according to an embodiment.

As shown in FIG. 1, an offset type parabolic antenna is used as the receiving antenna 2, and a reflecting mirror 4 of the receiving antenna 2 is fixed to fix the receiving antenna 2 on a roof or the ground. It is attached to a support 6 erected on a stand 7 via a support (not shown) capable of adjusting the elevation angle, azimuth angle, and in some cases, the rotation angle of the reflecting mirror 4. The support receives vertical and horizontal polarized radio waves from each of the satellites A and B collected by the reflecting mirror 4 and transmits either polarized signal to a predetermined frequency band (950 to 950).
A converter 30 that converts the signal into a first intermediate frequency signal (RF signal) of 2150 MHz and outputs the converted signal is attached via a support arm 8.

As shown in FIG. 2, the converter 30 applies vertical and horizontal polarized waves from the satellite A, which are collected by the reflecting mirror 4 and guided by the circular waveguide 32, via the probes P1 and P2. And a vertical receiving unit 34 for receiving vertical and horizontal polarized waves from the satellite B similarly collected by the reflecting mirror 4 and guided to the circular waveguide 33 via the probes P3 and P4. Two wave receiving units 35 are provided.

The first wave receiving section 34 includes a probe P
1 and P2, that is, a vertical polarization signal amplification circuit 34a and a horizontal polarization signal amplification circuit 34b that amplify the vertical and horizontal polarization signals, respectively, and each polarization signal amplification circuit 34
a and a mixing circuit 34c for mixing output signals from 34b. On the other hand, the second wave receiving unit 35 includes the first wave receiving unit 3.
4 and a vertical polarization signal amplification circuit 35a and a horizontal polarization signal amplification circuit 35b that amplify the vertical and horizontal polarization signals from the probes P3 and P4, respectively.
And a mixing circuit 35c for mixing output signals from the respective polarization signal amplification circuits 35a and 35b.

Each of the polarization signal amplifier circuits 34a and 34a
b, 35a, and 35b each include a well-known low-noise amplifier circuit mainly composed of a high electron mobility transistor (HEMT) that operates by receiving positive and negative power supply voltages.
The positive power supply + Vv is applied to the vertical polarization signal amplifying circuits 34a and 35a, and the positive power supply + Vh is applied to the horizontal polarization signal amplifying circuits 34b and 35b. The amplifier circuits 34a and 34b have a negative power supply -Va,
A negative power supply -Vb is applied to both the polarization signal amplification circuits 35a and 35b of the reception unit 35. Then, one of positive power supply + Vv and + Vh from a positive power supply circuit 45 described later,
And a negative power supply -Va, -V
b, and selectively drives any one of the polarization signal amplifier circuits 34a, 34b, 35a, and 35b to which both positive and negative power supplies are applied in accordance with the combination of the supplied positive and negative power supplies. It has been like that.

The converter 30 includes a plurality of wave receiving units 34,
A mixing circuit 36 for mixing the output signals from the mixer 35 and a high-frequency amplifier 37 for amplifying the output signals from the mixing circuit 36
And the output signal from the high-frequency amplifier circuit 37 is mixed with the output signal from the local oscillator circuit 38 to convert the frequency, and
A mixer 39 for generating an F signal; and an intermediate frequency amplifying circuit 40 for amplifying the RF signal generated by the mixer 39. The amplified RF signal is supplied to a DC blocking capacitor 4
1. It is configured to output to the transmission line 9 (see FIG. 1) via the input / output terminal 42.

Further, the converter 30 includes a capacitor C
, C2, and a coil L. The low-pass filter 43 extracts only a DC component from an input applied to the input / output terminal 42 via the transmission line 9, and the components of the converter 30 based on the output of the low-pass filter 43. And a constant voltage circuit 44 for generating a positive power supply + Vc and a negative power supply -Vc for driving the first and second receiving units 34 and 35.
positive power supply circuit 45 for supplying any one of v and + Vh
And a negative power supply -Va,-
Vb, which supplies one of Vb, and the output voltage of the low-pass filter 43 (hereinafter referred to as the power supply voltage).
Is compared with a preset comparison voltage (13 V in this embodiment), and if the voltage is smaller than the comparison voltage, the positive power supply circuit 45 is controlled so that the positive power supply + Vv is supplied. To the polarization switching control circuit 47 and the input applied to the input / output terminal 42, a tone signal (32 k to
(53 kHz) is superimposed, and a satellite switching control circuit 48 that controls the negative power supply circuit 46 so that the negative power supply -Va is supplied if it is superimposed and the negative power supply -Vb is supplied if it is not superimposed. And

That is, in the converter 30, the input / output terminal 4
2 designates either satellite A or B depending on whether a tone signal is superimposed on the input from 2, and designates either vertical or horizontal polarization depending on whether the power supply voltage is smaller than the comparison voltage. The designated polarized wave received from the designated satellite is converted into an RF signal and output from the input / output terminal 42.

The positive power supply circuit 45, the negative power supply circuit 46, the polarization switching control circuit 47, and the satellite switching control circuit 48
Are described in, for example, JP-A-4-135328 and
Since it is a well-known one described in, for example, Japanese Patent Publication No. -171043, a detailed description thereof will be omitted here.

Next, the reception status display device 10 of the present embodiment
As shown in FIG. 1, a DC component serving as a power source of the converter 30 is applied to the transmission line 9 via the input / output terminal 11 and an RF signal from the converter 30 input through the transmission line 9 is supplied to the DC line. Power supply separation filter 1 for separating components
2, a variable amplifier 23 for amplifying and attenuating the RF signal separated by the power supply separation filter 12 in accordance with the gain control signal Sg, and a 400 MHz band signal for a specific channel signal in the RF signal specified by the tuning signal Ss. (Center frequency 40
A channel selecting circuit 13 for converting and outputting a second intermediate frequency signal (IF signal) of 2.78 MHz (corresponding to an output frequency); a demodulating circuit 14 for demodulating the IF signal from the channel selecting circuit 13;
An A / D converter 15 is provided for converting the voltage level of the demodulated signal generated by the demodulation circuit 14 (ie, the signal level of the channel selected by the channel selection circuit 13) into a digital value.

The variable amplifier 23 converts an RF signal into a signal level that can be processed by the demodulation circuit 14, and may be omitted if the dynamic range of the demodulation circuit 14 is sufficiently wide. . Further, the reception status display device 10 includes an operation unit 16 for specifying a satellite, a polarization, a channel, and an operation mode to be described later, which are display targets of the reception status, a display device 17 including a liquid crystal display panel, and the like.
A display control circuit 18 for driving the display device 17 and a DC component to be supplied to the converter 30 are generated, and the voltage (supply voltage) is changed to a high voltage for horizontal polarization designation (this embodiment) according to the polarization switching signal Sv. Voltage generator 19 for setting to 15 V in the embodiment or a low voltage for selecting vertical polarization (11 V in the present embodiment), and a tone signal generator 20 for generating a tone signal in accordance with the satellite switching signal St.
A signal superimposing circuit 21 for superimposing a tone signal on a DC component generated by the voltage generating circuit 19 and supplying the superposed tone signal to a power supply separation filter, and a well-known microcomputer mainly composed of a CPU, a ROM, and a RAM. The gain control signal Sg, the tuning signal Ss, the polarization switching signal Sv, and the satellite switching signal St are set according to the operation of the unit 16, and the specified display mode is set based on the voltage level read via the A / D converter 15. Display control circuit 18 according to the
And a control circuit 22 for executing a display control for displaying on the display device 17 through the display device 17.

The signal superposition circuit 21 includes a transistor TR1 and resistors R1 and R2, a first switching circuit for interrupting a power supply path from the voltage generation circuit 19 to the power supply separation filter 12, and a transistor having a power supply direction in the forward direction. It comprises a diode D connected in parallel with TR1, a transistor TR2, resistors R3 and R4, and a second switching circuit for controlling ON / OFF of the first switching circuit according to the tone signal output from the tone signal generating circuit 20.

The output of the tone signal generating circuit 20 is
In the case of the High level, both the first and second switching circuits (that is, the transistors TR1 and TR2) are turned on, so that the power supply voltage supplied to the power supply separation filter 12 T
The voltage drop at the collector-emitter voltage of R1 (0.1
０．３0.3 V). On the other hand, when the output of the tone signal generation circuit 20 is at the low level, the first and second switching circuits are both turned off, so that the power supply voltage supplied to the power supply separation filter 12 is equal to the output voltage of the voltage generation circuit 19. Accordingly, the voltage becomes smaller by the forward voltage (0.7 to 0.9 V) of the diode D.

Therefore, when the tone signal is output from the tone signal generation circuit 20, the tone signal having an amplitude of 0.6 ± 0.2 [V] is superimposed on the DC component output from the voltage generation circuit 19. Is supplied to the power supply separation filter 12. And, as described above, satellite A
Is designated, a tone signal is superimposed when satellite B is designated, and a tone signal is not superimposed when satellite B is designated. When horizontal polarization is designated, the supply voltage is set to 15 V, and vertical polarization is designated. Since the power supply voltage is set to 11 V when specified, the output waveform of the signal superposition circuit 21 in each case of combining these, that is, the transmission line 9
The waveform of the component supplied to the converter 30 through the above is as shown in FIG.

FIG. 4 shows the actual display contents on the display device 17, and as shown in FIG. 4, the display device 17 displays the type of satellite designated to display the reception status, The type of polarization and the selected channel are displayed, and the signal level of the selected channel is numerically displayed in dBμ units and displayed as a bar as an analog signal.

However, the operation mode set by the operation unit 16 includes an individual mode for displaying the signal level of one of the polarizations of one of the satellites, and both of the two modes for the one of the polarizations. There is a comparison mode in which a signal level reflecting the reception state of the satellite is displayed. And in the case of the comparison mode, the area where the type of satellite is displayed
A message indicating that the mode is the comparison mode is displayed.

Next, the display control executed by the control circuit 22 will be described for each operation mode. First, the display control executed in the individual mode will be described with reference to the flowchart shown in FIG. Before this processing is started, the type of satellite, the type of polarization, and the channel whose reception status is to be displayed are set via the operation unit 16, and the setting contents are set to RA.
It is assumed that it is stored in a predetermined area of M. Once the process is started, it is repeatedly executed thereafter. However, if the above setting is changed via the operation unit 16 during execution, the stored value in the RAM is changed according to the change. Shall be updated.

As shown in FIG. 5, when the present process is started, first, in S110 (hereinafter, "S" indicates a step), the setting contents stored in the RAM in advance are read. In subsequent S120, it is determined whether or not the satellite A is designated as the type of satellite based on the setting content read in S110. If the determination is affirmative, the process proceeds to S130, where the tone signal generation circuit 20 After the satellite switching signal St is set so that a tone signal is output from, the process proceeds to S150. On the other hand, if a negative determination is made in S120, S1
40, and after setting the satellite switching signal St so that the tone signal is not output from the tone signal generating circuit 20,
Proceed to S150.

In S150, it is determined whether or not horizontal polarization is designated as the type of polarization based on the setting contents read in S110.
The process proceeds to S60, where the polarization switching signal Sv is set so that the power supply voltage from the voltage generation circuit 19 becomes a high voltage (15V), and then the process proceeds to S180. On the other hand, when a negative determination is made in S150, the process proceeds to S170 to set the polarization switching signal Sv so that the power supply voltage from the voltage generation circuit 19 becomes a low voltage (11 V), and then proceeds to S180.

As described above, the presence / absence of a tone signal and the magnitude of the power supply voltage are set in accordance with the designation of the satellite and the polarization in the set contents, and power is supplied to the converter 30 of the receiving antenna 2. Is supplied with an RF signal obtained by receiving radio waves of a designated polarization from a designated satellite.

At S180, based on the setting contents read at S110, a signal of a designated channel is selected from the RF signals by the tuning circuit 13 and converted into an IF signal. Ss is set, and the following S19
At 0, the voltage level of the demodulated signal obtained by demodulating the IF signal from the tuning circuit 13 by the demodulation circuit 14 is read from the A / D converter 15, and at S200, the read voltage level ("reception" Is converted to a value of the determined unit (dBμ), and displayed on the display device 17 together with the setting content read in S110, and this processing ends. The contents displayed on the display device 17 are as follows:
00 is held until it is executed, and is updated every time S200 is executed.

Next, the display control executed in the comparison mode will be described with reference to the flowchart shown in FIG. Note that, as in the individual mode, before this processing is started,
It is assumed that the type of satellite, the type of polarization, and the channel whose reception status is to be displayed are set via the operation unit 16, and the set contents are stored in a predetermined area of the RAM.

As shown in FIG. 6, when this processing is started, first in S210, as in S110, R
The setting contents stored in the AM are read. However, in the comparison mode, the type of satellite is ignored, and only the type of polarization and the channel are read. In subsequent S220, S21
Based on the setting contents read at 0, it is determined whether or not horizontal polarization is designated as the type of polarization. If the determination is affirmative, the process proceeds to S230 and the voltage generation circuit 19
After the polarization switching signal Sv is set so that the power supply voltage from is high (15 V), the process proceeds to S250. On the other hand, S22
If a negative determination is made at 0, the process proceeds to S240,
After setting the polarization switching signal Sv so that the power supply voltage from the voltage generation circuit 19 becomes a low voltage (11 V), the process proceeds to S250.

In S250, the satellite switching signal St is set so that the tone signal is output from the tone signal generation circuit 20, that is, the radio signal from the satellite A is received.
In steps S60 and S270, the setting of the channel selection signal Ss and the reading of the voltage level (that is, the reception level) LV1 of the demodulated signal are performed in exactly the same manner as in steps S180 and S190.

In the following S280, the tone signal generating circuit 2
The satellite switching signal St is set so that a tone signal is not output from 0, that is, a radio wave from the satellite B is received, and in subsequent S290 and S300, the tuning signal Ss is set just like S180 and S190. Then, the voltage level (ie, reception level) LV2 of the demodulated signal is read. Then, in S310, the reception levels LV1 and LV2 read in S270 and S300 are converted into the determined unit (dB).
μ), and further calculates the display level LVD according to the following equation (2).

LVD = | LV1 + LV2 | − | LV1-LV2 | (2) That is, from the sum | LV1 + LV2 |
The display level LVD is obtained by subtracting the difference | LV1-LV2 | between the two reception levels. In subsequent S320, S31
The display level LVD calculated at 0 is displayed on the display device 17 together with the setting contents read at S210, and the process ends. The contents displayed on the display device 17 are held until the next execution of S310, and are updated each time S310 is executed.

Since the display level LVD is different from the original signal level, the user may have anxiety about whether or not the radio waves from the satellites A and B are actually received. Therefore, the display level LVD may be applied only to the bar display, and one of the reception levels LV1 and LV2 may be numerically displayed.

As described above, according to the reception state display device 10 of the present embodiment, by operating in the individual mode, not only can the reception level of the desired polarization of the desired artificial satellite be individually displayed, but also the comparison can be made. By operating in the mode, the reception levels LV1, LV of both satellites A, B
2, the display level LVD can be displayed such that the larger the two reception levels LV1 and LV2 are, and the smaller the difference between the two reception levels LV1 and LV2 is, the larger the value becomes.

For this reason, if the reception state display device 10 of the present embodiment is used in the comparison mode, the direction and the polarization plane of the reception antenna 2 that receives orthogonally polarized waves from the two satellites A and B can be adjusted. The following procedure can be used. procedure. First, the mounting angle of the converter 30 corresponding to the receiving area is determined according to a preset chart, and the converter 30 is temporarily fixed to the support arm 8 according to the determined mounting angle.

Procedure. The elevation angle of the reception antenna 2 (reflecting mirror 4) corresponding to the reception area is determined according to a chart set in advance, and the reception antenna 2 is temporarily fixed with the support so as to have the determined elevation angle. procedure. The operation unit 16 of the reception state display device 10 is used to set the operation mode (comparison mode), the polarization for displaying the reception state, and the channel, start the display control, and display the display level LVD of the specified channel. It is displayed on the device 17.

Thereafter, when the receiving antenna 2 is rotated about the support 6 to change the azimuth, the receiving state changes with this rotation, and the value of the display level LVD of the display device 17 also changes. procedure. While confirming the display level LVD displayed on the display device 17, the azimuth of the receiving antenna 2 is adjusted so that the level becomes the maximum (peak), and the receiving antenna 2 is fixed by the support.

Procedure. The operation unit 16 is operated to switch the designation of the polarization and the channel, the inclination of the converter 30 is adjusted so that a good signal level is obtained for both polarizations, and the converter 30 is fixed to the support arm 8. As described above, if the reception status display device 10 of the present embodiment is used, the display device 17
By simply adjusting the direction of the receiving antenna 2 so that the display level LVD displayed at the peak becomes the peak, it is possible to easily find the direction in which both the radio waves from the satellites A and B are in a good reception state.

FIG. 7 is a graph showing the measured signal level and the display level LVD obtained from the measured value when operating in the comparison mode. However, here, the receiving antenna 2 is JCSAT3 and JCSAT.
The elevation angle was set so that the radio wave from No. 4 was received, and the measurement was performed while changing the azimuth angle. As shown in the figure, the display level LVD has a peak at a point (at an angle of 0 ° in the figure) that is larger than the noise level (about 60 dBμ) and the reception levels from both artificial satellites are equal.

In this graph, the peak of the display level LVD appears even when the azimuth is in the vicinity of −30 °, which is caused by other artificial satellites (here, Superbird C and JCS).
AT1). However, this display level LVD is smaller than the peak based on the radio wave from the target artificial satellite, and has an azimuth of about 30 degrees.
Since the angles are also different, the possibility of misalignment during actual adjustment is extremely low.

In this embodiment, the voltage generation circuit 19, the signal superposition circuit 21 and S250 and S280 are selection signal generation means, and the channel selection circuits 13 and S180 are channel selection means.
A / D converter 15 and S270 and S300 are level detecting means, S310 is display level calculating means, and display device 1
7. The display control circuit 18 and S320 correspond to a display unit.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.
It can be implemented in various ways. For example, in the above embodiment, in the comparison mode, only the display level calculated from the actual measured value of the signal level is displayed. However, the actual measured value of the signal level is also displayed simultaneously with the display level or by performing a switching operation. You may comprise so that it may display.

In the above-described embodiment, the display device 17 incorporated in the reception status display device 10 is used, but the information of the reception status is converted into image information to generate a video signal. The video signal may be input to an external television receiver or the like and displayed.

Further, in the above-described embodiment, the display level LVD is displayed only for one of the polarized waves during the operation in the comparison mode. However, in the display control, the switching of the satellite (tone signal) is performed. Not only that, the polarization (power supply voltage) may be switched automatically, and the display levels LVD of both polarizations may be displayed simultaneously.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an entire reception state display device according to an embodiment.

FIG. 2 is a block diagram illustrating a schematic configuration of a converter.

FIG. 3 is a graph showing an output waveform of a signal superposition circuit.

FIG. 4 is an explanatory diagram showing display contents on a display device.

FIG. 5 is a flowchart illustrating processing contents of display control (individual mode).

FIG. 6 is a flowchart illustrating processing contents of display control (comparison mode).

FIG. 7 is a graph showing measured signal levels and display levels determined from the measured values.

[Explanation of symbols]

2 receiving antenna, 4 reflecting mirror, 6 support, 7 fixing stand, 8 support arm, 9 transmission line, 10 reception status display device, 11 42 input / output terminal, 12 power supply separation filter, 13 channel selection circuit, 14 demodulation circuit, 15 A / D converter, 16 operation unit, 17 display device, 18 display control circuit, 19 voltage generation circuit, 20 tone signal generation circuit, 21 signal Superimposition circuit, 22 control circuit, 23 variable amplifier, 30 converter, 32, 33 circular waveguide, 34 first receiving part, 35 second receiving part, 36 mixing circuit, 37 high frequency Amplifying circuit, 38 local oscillation circuit, 3
9: mixer, 40: intermediate frequency amplifying circuit, 41: capacitor, 43: low-pass filter, 44: constant voltage circuit, 45
... Positive power supply circuit, 46 ... Negative power supply circuit, 47 ... Polarization switching control circuit, 48 ... Satellite switching control circuit, P1 to P4 ...
Probe, R1 to R4 ... resistance, TR1, TR2 ... transistor

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) GG26 GG44 HH08

Claims (2)

[Claims] 1. A satellite selection signal for designating an artificial satellite is supplied to a receiving antenna that receives radio waves from two artificial satellites at the same time and outputs a received signal for a designated artificial satellite. A reception state display device for displaying the reception state of the reception signal supplied from the reception antenna, wherein a channel selection means for extracting a signal of a preset designated channel from a reception signal input from the reception antenna; Level detection means for detecting the signal level of the signal extracted by the station means; selection signal generation means for generating the satellite selection signal so that the designation of the artificial satellite is alternately switched; and detection by the level detection means A display that calculates a display level by subtracting the difference between the two signal levels from the sum of the two signal levels based on the signal levels of the two artificial satellites And Bell calculating means, the display of the display level calculated by the level calculation means, display means for displaying a reception state of the received signal, the reception state display apparatus comprising: a. 2. The radio wave received by the receiving antenna from the artificial satellite is composed of two orthogonal polarizations, and the selection signal generating means also generates a polarization selection signal for specifying polarization according to an external designation. The reception status display device according to claim 1, wherein the reception status display is performed.