JP3459395B2 - CS broadcast dual antenna reception level measurement method and measurement device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for measuring the reception level of a CS broadcast dual antenna.

[0002]

2. Description of the Related Art In recent years, the number of satellite broadcasts such as BS broadcasts and CS broadcasts has been increasing. Further, in CS broadcasting (CS digital broadcasting), JC-SAT No. 3 and JC-S at very narrow intervals on the same orbit, for example, at an angle of 4 °.
The satellite of AT4 has been launched. Above JC-SA
CS transmitted from T3 and JC-SAT4 satellites
Broadcasts can be received with dedicated parabolic antennas, but recently, one receiving antenna has two C channels.
A CS broadcast dual antenna capable of receiving S broadcast has been put into practical use. This CS broadcast dual antenna has two converters for one parabolic reflector, namely, a JC-SAT3 broadcast receiving converter and a JC.
-A converter for receiving broadcast of SAT4 is provided.

[0003]

The above-mentioned CS broadcast dual antenna is very convenient because one antenna can receive two CS broadcasts. However, when the CS broadcast dual antenna is installed, its position must be adjusted so as to correspond to the two satellites, which is very troublesome to adjust. Generally, the direction of the antenna is adjusted while checking the television received image, but it is difficult for one person to adjust the direction of the antenna because the television receiver is installed away from the antenna. For this reason, a level meter has been put into practical use, which can confirm the level of the received signal of the antenna at or near the place where the antenna is installed.

The above-mentioned conventional level meter outputs JC-SAT3 broadcast and JC-SAT output from two converters.
Each of the SAT No. 4 broadcasts is received and the level of the received signal is displayed by a meter. In the adjustment, if the direction of the antenna is roughly aligned with the direction of the satellite and then the antenna is moved left and right, the deflection of the meter increases when the direction of the antenna coincides with the direction of the satellite. However, since broadcast radio waves are being output from two satellites, JC-SAT3 and JC-SAT4 are compatible.
The maximum value of the meter will appear in two places that match the number, and it is not possible to confirm which is the optimum place. In addition, both radio wave of each other to effect deflection of the meter by receiving broadcast waves from two satellites changes complicated, it is difficult to any point for this is to check whether the optimum direction.

Further, since the conventional level meter is constructed so as to take out the intermediate frequency signal output from the internal tuner and measure the signal level thereof, the frequency of the signal to be handled is high and the construction of the measuring circuit. However, there is a problem in that it becomes complicated and the cost becomes high.

The present invention has been made to solve the above problems, and when adjusting the direction of the antenna, the maximum value of the meter can be set to one position, and the direction can be adjusted reliably and easily. An object of the present invention is to provide a method and apparatus for measuring the reception level of a CS broadcast dual antenna that can reduce the cost.

[0007]

According to a first aspect of the present invention, a tuner receives an output signal of a CS broadcasting dual antenna equipped with two converters corresponding to two satellites, and the antenna uses the AGC signal output from the tuner. In the method for measuring the reception level of a CS broadcast dual antenna for measuring the reception level of the above, the reception channel of the tuner is set to the broadcast channel of the frequency used by only one of the two satellites, and the level of the reception radio wave is set. Characterized by measuring.

A CS broadcast dual antenna reception level measuring apparatus according to a second aspect of the present invention includes a tuner for receiving an output signal of the CS broadcast dual antenna provided with two converters corresponding to two satellites, and a tuner for outputting the output signal. A
A current amplifier for amplifying a GC signal, a meter driven by an output signal of the current amplifier, and channel setting means for setting a receiving channel of the tuner are provided, and the channel setting means sets the receiving channel of the tuner. It is characterized in that the broadcast channel is set to the frequency used by only one of the two satellites.

A receiving level measuring apparatus for a CS broadcasting dual antenna according to a third aspect of the present invention includes a tuner for receiving an output signal of the CS broadcasting dual antenna provided with two converters corresponding to two satellites, and an output signal from this tuner. A
A current amplifier for amplifying a GC signal, a meter driven by an output signal of the current amplifier, a channel setting means for outputting a plurality of channel setting signals for the tuner, and a channel setting signal output from the channel setting means are provided. The channel setting means outputs a plurality of channel setting signals corresponding to a broadcasting channel of a frequency used by only one of the two satellites. It is characterized by

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit configuration diagram of a reception level measuring device for a CS broadcast dual antenna according to an embodiment of the present invention. In the figure, 10 is a CS broadcasting dual antenna, and one parabolic reflector 11 has JC
-First converter 1 for SAT3 broadcast (PerfecTV)
2 and a second converter 13 for JC-SAT No. 4 broadcasting (JSkyB). The output signals of the first converter 12 and the second converter 13 are mixed by the mixer 14, and output from the coaxial connector 15 provided in the mixer 14. CS broadcasting dual antenna 1
As 0, those having a local oscillation frequency of “11.2 GHz” and those having a local oscillation frequency of “10.678 GHz” have been generally used conventionally.

When the television receiver receives the CS broadcast, it is connected from the coaxial connector 15 of the mixer 14 to a CS tuner (not shown) via a coaxial cable, but the CS broadcast dual antenna 10 is received. When measuring the level, use the coaxial connector 15 to the coaxial cable 1
It is connected to the reception level measuring device (level meter) 20 of the CS broadcast dual antenna via 6. In addition, the above CS
The broadcast dual antenna 10 is a television receiver C.
It operates by an S tuner or a DC power supply supplied from the reception level measuring device 20.

The reception level measuring device 20 includes a tuner 21 for receiving a CS broadcast. The tuner 21
Includes an antenna input terminal 22 and a tuner output terminal 23.
And the antenna input terminal 22 is connected to the coaxial connector 15 of the mixer 14 via the coaxial cable 16.
Connected to. The tuner 21 has an antenna input terminal 22.
Tuner input terminal 23 by branching the received signal input to
Output to. A CS tuner of a television receiver is connected to the tuner output terminal 23 by a coaxial cable, if necessary.

In the tuner 21, a plurality of channel setting signals output from the channel setting circuit 24 are selected by the tuning switch 25 and input to the TUV terminal. The channel setting circuit 24 is a JC-SAT3.
No. or JC-SAT4 so that the channel transmitted by only one of them can be received, for example, JC-SAT
Broadcast channel JD25 (Transmission frequency 1
2.428 GHz). The tuning switch 25 operates according to the type of the CS broadcast dual antenna 10, that is, the CS broadcast dual antenna 10.
The channel setting signal of the channel setting circuit 24 is selected according to the local oscillation frequency used by the tuner 2
Input to the 1 TUV terminal. In this case, tuning switch 2
For example, the selected channel of # 1 according to 5 is a dual antenna having a local oscillation frequency of “11.2 GHz”, and the selected channel of # 2 has a local oscillation frequency of “10.678 GH”.
It is compatible with the "z" dual antenna.

In FIG. 1, the channel setting circuit 24
In addition to the channels # 1 and # 2, the channels # 3 to # 6 can be selected by the tuning switch 25, which is dedicated to receiving the radio waves of other CS satellites and BS satellites. When an antenna is installed, the reception level of the corresponding satellite radio wave can be measured.

An operating voltage of, for example, 12 V is input to the LNB terminal of the tuner 21 from the DC power source 26 via the power source switch 27a, a protection circuit 28, which will be described in detail later, and a power source line 29. As the DC power supply 26, for example, eight 1.5 V batteries are used, and a total voltage of 12 V is obtained.

The tuner 21 has a tuner output terminal 2
When the CS tuner of the television receiver is connected to 3, the power supplied from the CS tuner is, for example, 12V.
And outputs the DC voltage to the antenna input terminal 22 and the LNB terminal. In this case, the DC voltage output from the LNB terminal to the power supply line 29 is prevented from affecting the DC power supply 26 by the protection circuit 28. An LED 31 is connected via a resistor 32 between the power supply line 29 and the ground line GND.

Further, 1 supplied to the power supply line 29
The voltage of 2V is supplied to the channel setting circuit 24, converted into a voltage of 5V by the voltage conversion circuit 33, and supplied to the tuner 21 as an operating voltage.

Then, the AGC signal output from the tuner 21 is amplified by the current amplifier 34, and is then metered by the meter 35.
To drive. Details of the current amplifier 34 will be described later. The meter 35 is, for example, 200 μA,
One end is connected to the power supply line 29, and the other end is connected to the output end of the current amplifier 34 via the power switch 27b. The current amplifier 34 is provided with a sensitivity adjusting volume 36 for adjusting the shake state of the needle of the meter 35.

The power switches 27a and 27b operate in conjunction with each other, and are configured so that the three terminals a, b and c are switched by the movable contact d. The terminal a of the power switch 27a is power OFF, the terminal b is power ON, the terminal c is a terminal for power check (CHECK), the terminal a is open, the terminals b and c are connected to the + terminal of the DC power supply 26,
The common contact d is connected to the protection circuit 28. The terminals a and b of the power switch 27b are connected to the output terminal of the current amplifier 34, the terminal c is connected to the ground line GND via the variable resistor 37 and the resistor 38, and the movable contact d is the meter 35.
Connected to.

FIG. 2 shows a circuit configuration of the protection circuit 28. The input terminal T1 of the protection circuit 28 is connected to the emitter of, for example, a PNP transistor 41 via a resistor 40, and its collector is connected to the output terminal T2 via a diode 42 in the forward direction. A resistor 43 and a large-capacity capacitor 44 are connected in parallel to the resistor 40. Further, the resistor 45 is connected between the emitter and the base of the transistor 41, and the collector-base resistor 46 is connected. Further, the input terminal T1 is connected to, for example, the emitter of a PNP type transistor 47,
Its base is connected to the base of the transistor 41. The collector of the transistor 47 is connected to the base of the transistor 41 and also connected to the ground line GND via the resistor 48. The protection circuit 28 is
As shown in FIG. 1, the DC power supply 26 is a power switch 27a.
Is supplied to the input terminal T1 through the output terminal T2, and the output terminal T2 is connected to the power supply line 29.

The protection circuit 28 includes a power switch 27.
When a and 27b are turned on, the DC power supply 26 is connected to the input terminal T
1, so that the transistor 41 is turned on. Therefore, the DC power supply 26 supplied to the input terminal T1
Is output to the power supply line 29 via the diode 42 and the output terminal T2.

In the above state, when a larger current than a preset value flows through the load circuit of the protection circuit 28, the voltage drop due to the resistors 40 and 43 increases, the base voltage of the transistor 47 decreases, and the transistor 47 turns on.
Then, a reverse bias voltage is applied to the base of the transistor 41. Therefore, the transistor 41 is turned off to protect the load circuit. The above state is held by the charging voltage of the large-capacity capacitor 44.

When the load circuit is cut off by the protection circuit 28 as described above, the power switches 27a and 27b are turned off.
After FF and the load circuit returns to normal, the power switches 27a and 27b are turned on again. The power switch 27
When a and 27b are once turned off, the electric charge charged in the capacitor 44 is discharged through the resistors 40 and 43 and returns to the initial state. Therefore, when the power switches 27a and 27b are turned on again, the transistor 41 is turned on and the power line The DC power supply 26 is supplied to 29. Further, the diode 42 has a voltage supplied from the CS tuner of the television receiver,
It has a function of cutting off the DC power supply 26.

FIG. 3 shows a circuit configuration of the current amplifier 34. A diode 52 and a semi-fixed resistor 53 are provided in series between the AGC signal input terminal 51 and the ground line GND, and a capacitor 54 is provided in parallel with the semi-fixed resistor 53. The sliding terminal of the semi-fixed resistor 53 is connected to the base of, for example, an NPN transistor 57 via a resistor 55, and is also connected to the emitter via a resistor 56. This emitter and ground line GV
The sensitivity adjusting potentiometer 36 is provided between it and D. The collector of the transistor 57 is connected to the meter 35 via the power switch 27b.

In the above structure, the signal level of the AGC signal input from the tuner 21 to the current amplifier 34 is adjusted by the semi-fixed resistor 53 and the transistor 57 is adjusted.
Entered in. The transistor 57 is the input AGC
The signal is current-amplified and the meter 35 is driven. in this case,
The deflection of the needle in the meter 35 is adjusted by the sensitivity adjusting volume 36.

In FIG. 4, in the current amplifier 34, the value of the semi-fixed resistor 53 is [100 KΩ], the value of the resistor 55 is [160 KΩ], the value of the resistor 56 is [33 KΩ], and the value of the sensitivity adjusting potentiometer 36. [0Ω], [1.2K
3 shows the relationship between the input current and the output current when variably set to [Ω], [2.5 KΩ], and [5 KΩ].

FIG. 5 shows an external configuration of the reception level measuring device (level meter) 20. Case 6
An antenna input terminal 22 and a tuner output terminal 23 are provided on the upper side of 0. Further, on the front surface of the case 60, the meter 35 is provided on the upper side and the LED is provided in the vicinity thereof.
31 is arranged. Further, on the front surface of the case 60, the local oscillation frequency is, for example, [1. Sky Perfec 11.2 GHz], [2. Sky Perf
ec 10.678 GHz], and a power switch 27 (27a, 27b) is provided. In the vicinity of the power switch 27, "OFF", "ON", "CHECK" corresponding to the position of the operation knob.
Is printed. A sensitivity adjusting volume 36 and a tuning switch 25 are provided on the right side of the case 60.

Next, an operation procedure for adjusting the direction using the reception level measuring device 20 when the CS broadcasting dual antenna 10 is installed will be described. First, the CS satellite which receives the dual antenna 10, in this case, the JC-SAT3 and JC-SAT4 are installed according to the general directions. Then, as shown in FIG. 1, the coaxial connector 15 of the dual antenna 10 and the antenna input terminal 22 of the reception level measuring device 20 are connected by a coaxial cable 16, and the tuning switch 25 is set to the type of the dual antenna 10, that is, , Set according to the local oscillation frequency. That is, if the dual antenna 10 is "11.
If you are using a local oscillation frequency of 2 GHz,
When the channel # 1 is selected by the channel selection switch 25 and the dual antenna 10 uses the local oscillation frequency of “10.678 GHz”, the channel # 2 is selected by the channel selection switch 25. When the converters 12 and 13 are operated by the power supply of the reception level measuring device 20, nothing is connected to the tuner output terminal 23.

Then, the sensitivity adjusting potentiometer 36 is set to the intermediate position and the power switch 27 is turned on. The ON state of the power switch 27 can be confirmed by lighting the LED 31. When the power switch 27 is turned on,
The DC power supply 26 is connected to the L of the tuner 21 via the protection circuit 28.
It is input to the NB terminal, and the mixer 14 and the converters 12 and 1 from the antenna input terminal 22 through the coaxial cable 16.
3 is supplied. As a result, converters 12 and 13 start the receiving operation. In this case, the tuner 21 is JC-
To be able to receive the channel transmitted by only one of SAT3 and JC-SAT4, that is,
In this embodiment, the broadcast channel JD25 (transmission frequency 12.428 GHz) in JC-SAT3 is set to be received.

The first converter 12 is a JC-SAT3.
When the signal of the channel JD25 (vertical polarization) with the frequency of 12.428 GHz transmitted from the signal is received, if the local oscillation frequency is "11.2 GHz", it is 1228 MHz.
Signal and the local oscillation frequency is "10.678GH
In the case of "z", it is converted into a signal of 1750 MHz and output. On the other hand, JC-SAT4 is the above-mentioned broadcasting channel J.
Since we are not broadcasting the frequency corresponding to D25,
From the second converter 13, the broadcast channel J
No signal having a frequency corresponding to D25 is output.

Therefore, the tuner 21 receives the "1228 MHz" signal output from the first converter 12 when the channel # 1 is selected, and the tuner 21 when the channel # 2 is selected. Is "1750 MH
z "signal is received.

In the above state, if the elevation angle and the polarization angle of the installed dual antenna 10 are temporarily fixed and the left and right sides are moved, for example, from the east side to the west side, when the reception signal is output from the first converter 12, the tuner 21 is output. An AGC signal is output from the meter 35, and the meter 35 swings according to its strength. Therefore, the meter 35 stops at the maximum swing. When the shake of the meter 35 is extremely small or large, the sensitivity adjusting volume 36 is used for adjustment.

Next, the dual antenna 10 is moved in the vertical direction and stopped at the position where the pointer of the meter 35 is maximized. The elevation angle and the polarization angle of the dual antenna 10 are adjusted as described above, and fixed at the position where the reception level is maximum.

When the direction of the dual antenna 10 is adjusted, the level of the received radio wave is measured by selecting the channel in which the radio wave is transmitted from only one satellite, that is, JC-SAT3, so that the level of the received radio wave is measured. There is only one maximum swing point, and JC-SAT3 and JC-S
Since the AT4 radio waves do not affect each other, the maximum point of the received radio waves can be surely and easily confirmed.

Further, if the direction for the first converter 12 that receives the transmission radio waves of JC-SAT3 is correctly adjusted, as a result, the direction for the second converter 13 that receives the transmission radio waves of JC-SAT4 is also correctly adjusted. To be done. Therefore, it is not necessary to adjust the direction of JC-SAT4 again.

Therefore, after the above adjustment operation is completed, the reception level measuring device 20 is removed from the dual antenna 10 and the CS tuner of the television receiver is connected, whereby the television receiver becomes JC-SAT3 and JC.
-It is possible to receive the CS broadcast radio waves transmitted from SAT No. 4 in the best condition. In addition, dual antenna 1
When an abnormality in the power supply system occurs on the 0 side and an excessive current flows, the protection circuit 28 operates to cut off the power supply to the power supply line 29 to protect the circuit.

The case where the power of the reception level measuring device 20 is supplied to the dual antenna 10 for level measurement has been described above. However, when the power from the CS tuner of the television receiver is supplied to the dual antenna 10. Turns on the power switch 27 of the reception level measuring device 20.
FF is performed, and the CS tuner of the television receiver is connected to the tuner output terminal 23 by a coaxial cable. When the CS tuner of the television receiver is connected to the tuner output terminal 23, the voltage supplied from the CS tuner is output to the converters 12 and 13 via the antenna input terminal 22, and the power line 2 is supplied from the LNB terminal of the tuner 21.
9 is output. Therefore, even when the power switch 27 is turned off, the reception level measuring device 20 operates normally by the power supply from the CS tuner.

Therefore, the elevation angle and the polarization angle of the dual antenna 10 can be adjusted in the same manner as when the power source of the reception level measuring device 20 is used as described above. Even if the power switch 27 is turned on in the state where the CS tuner is connected to the tuner output terminal 23 of the tuner 21, the diode 42 of the protection circuit 28 disconnects the DC power source 26 and the power source from the CS tuner. So there is no particular problem.

When checking the consumption state of the DC power supply 26, the power switch 27 is switched to the CHECK position. At this time, the DC power supply 26 is supplied to the meter 35 via the variable resistance 37 and the resistance 38, and the needle of the meter 35 swings according to the consumption state of the DC power supply 26, so that the quality of the DC power supply 26 can be confirmed.

In the above embodiment, the channel setting circuit 24 outputs the channel setting signal corresponding to one broadcast channel of the frequency used by only one of the two satellites. In addition, a plurality of broadcast channels of the frequency used by only one satellite are set in the channel setting circuit 24, for example, JC-S.
In addition to the broadcast channel JD25 (transmission frequency 12.428 GHz) in AT3, the same polarization method as JD25, in this case, vertically polarized JD21 (transmission frequency 1
2.348 GHz), JD23 (transmission frequency 12.38)
8 GHz) and the like, and the channel setting signal is switched by the tuning switch 25 to select the tuner 21.
You may enter it in.

With the above configuration, the broadcasting channel of the frequency used by only one of the two satellites is preset even if the other satellite will be used in the future. It is possible to surely and easily adjust the direction of the dual antenna 10 by using the other broadcast channel.

[0042]

As described above in detail, according to the present invention, C
When adjusting the direction of the S-broadcast dual antenna, the channel of the frequency used by only one satellite is selected and the level of the received radio wave is measured, so the maximum point of the vibration of the meter should be one. Therefore, the direction in which the reception level becomes maximum can be surely and easily confirmed, and the directions of the dual antennas can be adjusted correctly.

Further, according to the present invention, since the level of the received radio wave is measured by using the AGC signal output from the tuner, the meter can be driven only by current amplifying the AGC signal. Therefore, the circuit configuration can be simplified and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of a reception level measuring device for a CS broadcast dual antenna according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a protection circuit in the same embodiment.

FIG. 3 is a configuration diagram of a current amplifier according to the same embodiment.

FIG. 4 is a diagram showing a relationship between an input current and an output current of the current amplifier according to the same embodiment.

FIG. 5 is an external configuration diagram of a reception level measuring device in the same embodiment.

[Explanation of symbols]

10 dual antenna 11 Parabolic reflector 12 First converter 13 Second converter 14 Mixer 15 coaxial connector 16 coaxial cable 20 Reception level measuring device (level meter) 21 tuner 22 Antenna input terminal 23 Tuner output terminal 24-channel setting circuit 25 tuning switch 26 DC power supply 27 Power switch 28 Protection circuit 29 Power line 31 LED 33 Voltage conversion circuit 34 Current amplifier 35 meters 36 Sensitivity adjustment volume

Claims (3)

(57) [Claims] 1. A CS broadcast dual antenna in which an output signal of a CS broadcast dual antenna provided with two converters corresponding to two satellites is received by a tuner and the reception level of the antenna is measured by an AGC signal output from the tuner. In the method for measuring the reception level of the above, the CS reception dual channel is characterized in that the reception channel of the tuner is set to a broadcast channel of a frequency used by only one of the two satellites and the level of the received radio wave is measured. Antenna reception level measurement method. 2. A tuner for receiving an output signal of a CS broadcast dual antenna provided with two converters corresponding to two satellites, a current amplifier for amplifying an AGC signal output from this tuner, and an output signal of this current amplifier. And a channel setting means for setting the receiving channel of the tuner, wherein the channel setting means uses the receiving channel of the tuner at a frequency used by only one of the two satellites. C which is set to the broadcast channel of
S broadcast dual antenna reception level measuring device. 3. A tuner for receiving an output signal of a CS broadcasting dual antenna provided with two converters corresponding to two satellites, a current amplifier for amplifying an AGC signal output from this tuner, and an output signal of this current amplifier. , A channel setting means for outputting a plurality of channel setting signals to the tuner, and a tuning switch for selecting a channel setting signal output from the channel setting means and inputting it to the tuner. A receiving level measuring apparatus for a CS broadcasting dual antenna, wherein the channel setting means outputs a plurality of channel setting signals corresponding to a broadcasting channel of a frequency used by only one of the two satellites.