JP2002076978A - Radio-interference eliminating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely adjust phase without deteriorating the suppression performance of the elimination of a radio interference even when the quantity of phase adjustment is altered largely by the change or the like in the environment. SOLUTION: The radio-interference eliminating device 30 branches a part of an output signal from a transmitter 1 as a canceling signal by a directional coupler 31, and inputs it to a directional coupler 32 on the reception side through a variable attenuator 34, a variable phase shifter 35 and a sub-phase shifter 36. A monitor receiver 38 monitors the radio interference and inputs it to a canceling control section 40. The canceling control section 40 controls the variable attenuator 34 and the variable phase shifter 35 so that a wraparound radio interference is minimized by the receiving signal of the monitor receiver 38. The canceling control section 40 outputs a control signal for an alarm to a sub-phase shifter control circuit 37 when phase swinging between antennas is deviated from the adjusting range of the variable phase shifter 35, and switches the quantity of the phase shifting of the sub-phase shifter 36. Accordingly, the range of phase adjustment can be widened, and the device can also deal with any phase shift.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication system in which a transmitting antenna and a receiving antenna are arranged in close proximity to each other to remove an interfering wave from a transmitter to a receiver via the transmitting antenna and the receiving antenna. Related to the device.

[0002]

2. Description of the Related Art Conventionally, in a wireless communication system in which a transmitting antenna and a receiving antenna are arranged close to each other, when the transmitting frequency and the receiving frequency are close to each other, the transmitting device transmits the signal to the receiving antenna via the receiving antenna. The sneaking radio waves interfere with the receiver such as sensitivity suppression and transmitter noise.

In order to remove such an interference wave, a conventional wireless communication system uses an interference wave removal device shown in FIG. In FIG. 7, 1 is a transmitter (Tx),
The transmission frequency is set to f1. A receiver (Rx) 2 receives a radio wave having a frequency close to the transmission frequency f1, for example, a frequency f2 which is an adjacent channel. As described above, when the transmission frequency and the reception frequency are close to each other, the interference wave removing device 10 is installed between the transmitter 1 and the transmission antenna 3 and between the receiver 2 and the reception antenna 4.

[0004] The interference wave removing apparatus 10 connects a directional coupler 11 between a transmitter 1 and a transmitting antenna 3 and also connects a directional coupler 1 between a receiving antenna 4 and a receiver 2.
2, 13 are connected in series. The directional coupler 11
Branches a part of the output signal of the transmitter 1, for example, a signal of about 1/100 as an interference wave canceling signal (cancellation interference wave), and connects the variable attenuator 14, the variable phase shifter 15, and the auxiliary phase shift cable 16. The signal is input to the directional coupler 12 through the directional coupler 12.

The directional coupler 13 is connected to the receiver 2
, A part of the signal, for example, about 1/100 is branched and input to the monitor receiver 17. The monitor receiver 17 monitors the signal of the frequency f1 from the received signal, and inputs the signal to the cancellation control unit 19 via the A / D converter 18. The cancellation control unit 19 is configured using, for example, a microprocessor, and includes the monitor receiver 1.
The amount of attenuation of the variable attenuator 14 and the amount of phase shift of the variable phase shifter 15 are controlled via D / A converters 20 and 21 based on the signal of the frequency f1 input from. That is, the cancellation control unit 19 controls the variable attenuator 14 and the variable phase shifter 15 so that the signal of the frequency f1 monitored by the monitor receiver 17 is minimized.

[0006]

In the above-described conventional interference wave removing apparatus 10, the variable phase shifter 15 has a phase variable width of about 240 °, and assists the adjustment position to be at the center of the phase variable width. The length of the phase shift cable 16 is adjusted.

The phase variable width of the variable phase shifter 15 is about 240 ° as described above, and it is difficult to provide a phase variable width greater than this.

For this reason, conventionally, the auxiliary phase shift cable 16 is provided in series with the variable phase shifter 15, and the auxiliary phase shift cable 1 is arranged so that the adjustment position of the variable phase shifter 15 is located at the center of the phase variable width.
6 is adjusted so that it can cope with a phase change between the transmitting antenna 3 and the receiving antenna 4.

However, even when the auxiliary phase shift cable 16 is provided so that the adjustment position of the variable phase shifter 15 is located at the center of the variable width, a large change in the environment surrounding the antenna, for example, due to a building or a tree. However, when the environment changes greatly due to the change of the antenna or the relocation of the antenna, the amount of phase adjustment greatly changes, and the phase shift amount falls outside the variable range of the variable phase shifter 15.

As described above, the amount of phase adjustment changes greatly,
Conventionally, when the deviation from the variable range of the variable phase shifter 15 is achieved, the auxiliary phase shift cable 16 is replaced.

By providing a plurality of variable phase shifters 15, it is possible to obtain a variable amount of 360 ° or more, but the variable width per 1-bit control becomes large, and the canceling accuracy is reduced. There is a problem that the suppression performance of the interference wave removal is deteriorated.

Also, when an auxiliary attenuator (not shown) is provided for the variable attenuator 14, it is necessary to readjust the auxiliary attenuator as in the case of the variable phase shifter 15. In the case where the variable width of the variable attenuator 14 is set to be large, there is a problem that the suppression performance of the interference wave removal is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem. Even when the phase adjustment amount changes significantly due to a change in the environment or the like, the suppression performance of the interference wave removal is not deteriorated. An object of the present invention is to provide an interference wave removing device capable of performing phase adjustment reliably.

Further, according to the present invention, even when the amount of attenuation adjustment greatly changes due to a change in the environment, etc., the interference can be reliably adjusted without deteriorating the suppression performance of the interference wave removal. It is an object to provide a wave removing device.

[0015]

According to a first aspect of the present invention, there is provided an interfering wave removing apparatus for removing an interfering wave from a transmitter via a transmitting antenna and a receiving antenna disposed in close proximity to the receiver. Signal extracting means for extracting a part of the transmission signal sent to the antenna as an interference wave canceling signal, a variable attenuator for adjusting the level of the canceling signal extracted by the extracting means, and a variable shifter for adjusting the phase of the canceling signal. A phase shifter, at least one sub phase shifter including a fixed phase shifter and a bypass provided in series with the variable phase shifter, and adjustment by the variable attenuator, the variable phase shifter, and the sub phase shifter Combining means for combining the canceled signal with the received signal of the receiving antenna, and canceling an interference wave circulating from the transmitting antenna to the receiving antenna; A monitor receiver for monitoring the loop interference in the signal input to the receiver, and an attenuation amount of the variable attenuator and a shift of the variable phase shifter according to the loop interference monitored by the monitor receiver. A cancellation control unit for controlling the amount of phase, a phase change deviation detecting means for detecting a state in which a phase change between the transmitting antenna and the receiving antenna deviates from an adjustment range of the variable phase shifter, and a phase change deviation detecting unit. And a sub phase shifter control means for switching between a fixed phase shifter and a bypass in the sub phase shifter according to a deviation detection signal output from the means.

According to a second aspect of the present invention, there is provided an interfering wave removing apparatus for removing an interfering wave from a transmitter via a transmitting antenna and a closely arranged receiving antenna, the transmitting signal being transmitted from the transmitter to the transmitting antenna. , A variable attenuator for adjusting the level of the cancellation signal extracted by the extraction means, a variable phase shifter for adjusting the phase of the cancellation signal, and the variable Receiving at least one sub-attenuator comprising a fixed attenuator and a bypass provided in series with the attenuator, and a cancellation signal adjusted by the variable attenuator, the sub-attenuator, and the variable phase shifter; Coupling means for combining with a signal and canceling out an interference wave circulating from the transmitting antenna to the receiving antenna; and the receiver via the coupling means A monitor receiver for monitoring the loop interference in the input signal; and controlling the attenuation of the variable attenuator and the phase shift of the variable phase shifter in accordance with the loop interference monitored by the monitor receiver. A canceling control unit, an attenuation departure detecting means for detecting a state where the coupling attenuation between the transmitting antenna and the receiving antenna deviates from the adjustment range of the variable attenuator, and an output from the attenuation deviating detecting means. A sub-attenuator control means for switching between a fixed attenuator and a bypass in the sub-attenuator according to a deviation detection signal.

According to a third aspect of the present invention, there is provided an interfering wave removing apparatus for removing an interfering wave from a transmitter via a transmitting antenna and a closely arranged receiving antenna, the transmitting signal being transmitted from the transmitter to the transmitting antenna. , A variable attenuator that adjusts the level of the cancellation signal extracted by the extraction means, a variable phase shifter that adjusts the phase of the cancellation signal, and a variable phase shifter that adjusts the phase of the cancellation signal. At least one sub-phase shifter comprising a fixed phase shifter and a bypass provided in series with the phase shifter, and at least one sub-phase shifter comprising a fixed attenuator and a bypass provided in series with the variable attenuator; A sub-attenuator, combining the cancellation signal adjusted by the variable attenuator, the variable phase shifter, and the sub-phase shifter with the reception signal of the reception antenna; A coupling means for canceling an interference wave wrapping around from the antenna to the receiving antenna, a monitor receiver for monitoring the wraparound interference wave in a signal inputted to the receiver via the coupling means, and a monitor monitored by the monitor receiver. A cancellation control unit that controls the amount of attenuation of the variable attenuator and the amount of phase shift of the variable phase shifter in accordance with the sneaking wave, and that the phase change between the transmission antenna and the reception antenna adjusts the variable phase shifter. Phase change deviation detecting means for detecting a state deviating from a range, and a sub phase shifter control for switching between a fixed phase shifter and a bypass in the sub phase shifter according to a deviation detection signal output from the phase change deviation detecting means. Means for detecting a state in which the amount of coupling attenuation between the transmitting antenna and the receiving antenna deviates from the adjustment range of the variable attenuator; Deviation detection signal output from the characterized by comprising a sub-attenuator control means for switching the fixed attenuator and the side path in the sub attenuator.

According to a fourth aspect of the present invention, in the interference wave removing apparatus according to the first or third aspect, the sub phase shifter is provided by dividing a fixed phase shifter into a plurality.

According to a fifth aspect of the present invention, in the interference wave removing apparatus according to the first, second, or third aspect, the phase change deviation detecting means is provided in the canceling control unit.

According to a sixth aspect of the present invention, in the interfering wave removing apparatus according to the first, second or third aspect, the departure detecting means is provided in the cancellation control unit.

According to a seventh aspect of the present invention, in the interference wave removing apparatus according to the first, second or third aspect, the phase change deviation detecting means sets an upper limit of a control voltage supplied from the cancellation control unit to the variable phase shifter. It is characterized by comprising a window comparator for outputting a deviation detection signal in comparison with the set voltage and the lower limit set voltage.

According to an eighth aspect of the present invention, in the interference wave removing apparatus according to the first, second, or third aspect, the attenuation deviation detecting means sets an upper limit of the control voltage supplied from the cancellation control unit to the variable attenuator. A window comparator that outputs a deviation detection signal in comparison with the voltage and the lower limit setting voltage.

According to a ninth invention, in the interference wave canceling apparatus according to the first, second or third invention, the sub phase shifter control means comprises:
A pulse oscillator whose operation is controlled by a departure detection signal output from the phase change departure detection means, a flip-flop that inverts by a pulse signal output from the pulse oscillator, and the sub-transfer based on the output signal of the flip-flop A switching control means for switching between a fixed phase shifter of the phase shifter and a bypass is provided.

According to a tenth aspect, in the interference wave removing apparatus according to the first, second, or third aspect, the operation of the sub-attenuator control means is controlled by a departure detection signal output from the attenuation departure detection means. A pulse oscillator, a flip-flop that inverts by a pulse signal output from the pulse oscillator, and switching control means for switching between the fixed attenuator and the bypass of the sub-attenuator based on the output signal of the flip-flop. It is characterized by having.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a block diagram showing a configuration of an interference wave removing apparatus according to a first embodiment of the present invention. In the interference wave removing apparatus according to the first embodiment, a phase adjustment that satisfies the phase cancellation condition can be set in a wide range by providing a sub phase shifter for the variable phase shifter.

In FIG. 1, reference numeral 1 denotes a transmitter (Tx) whose transmission frequency is set to f1. A receiver (Rx) 2 receives a radio wave having a frequency close to the transmission frequency f1, for example, a frequency f2 which is an adjacent channel. Reference numeral 30 denotes an interference wave removing device provided between the transmitter 1 and the transmitting antenna 3 and between the receiver 2 and the receiving antenna 4.

The interference wave removing device 30 connects the directional coupler 31 between the transmitter 1 and the transmitting antenna 3 and also connects the directional coupler 3 between the receiving antenna 4 and the receiver 2.
2, 33 are connected in series. The directional coupler 31
Splits a part of the output signal of the transmitter 1, for example, a signal of about 1/100 as an interference wave canceling signal (cancelling interference wave), and switches the variable attenuator 34, the variable phase shifter 35 and the sub phase shifter 36. The signal is input to the directional coupler 32 through the directional coupler 32. The variable attenuator 34 is capable of varying the amount of attenuation in a range of, for example, 0 to 15 dB.
The phase shift amount is set to be variable within a range of 240 °. The sub phase shifter 36 basically has, for example, 1
It comprises an 80 ° fixed phase shifter and a bypass for bypassing the fixed phase shifter, and the auxiliary phase shifter control circuit 37 switches between the fixed phase shifter and the bypass. The details of the sub phase shifter 36 will be described later.

The directional coupler 33 branches a part of the signal input to the receiver 2, for example, a signal of about 1/100, and inputs the signal to the monitor receiver 38. This monitor receiver 3
8 monitors the signal of the frequency f1 from among the received signals,
The signal is input to the cancellation control unit 40 via the A / D converter 39. The cancellation control unit 40 is configured using, for example, a microprocessor, and calculates the amount of attenuation of the variable attenuator 34 and the amount of phase shift of the variable phase shifter 35 based on the signal of the frequency f1 input from the monitor receiver 38. / A converters 41 and 42
Control through.

That is, the cancellation control section 40 controls the variable attenuator 34 and the variable phase shifter 35 so that the signal of the frequency f1 monitored by the monitor receiver 38 is minimized, and furthermore, the transmission antenna 3 and the reception antenna 4 is within the adjustment range of the variable phase shifter 35 (about 0 ° to 240 °).
If you deviate, the cancellation condition will not be satisfied,
An alarm control signal (alarm signal) is output to the sub phase shifter control circuit 37. The sub phase shifter control circuit 37 alternately switches the phase circuit and the bypass of the sub phase shifter 36 every time a control signal (alarm signal) is given from the cancellation control unit 40. The phase variable width of the variable phase shifter 35 is about 0 ° to 240 °.
°, and the sub phase shifter 36 switches the phase shift function between 0 ° and 180 °, so that the total phase variable width is about 0 ° to 42 °.
It can be 0 °.

Next, details of the sub phase shifter 36 and the sub phase shifter control circuit 37 will be described with reference to FIG. The sub phase shifter 36 has a switch 51 at an input terminal and a switch 51 at an output terminal.
A fixed phase shifter 53 and a bypass 54 are provided between the switches 51 and 52. That is, the switch 5
The fixed phase shifter 53 is connected between the first contact a1 and the contact a2 of the switch 52, and the bypass 54 is connected between the contact b1 of the switch 51 and the contact b2 of the switch 52. The switches 51 and 52 operate in synchronization with a signal from the sub phase shifter control circuit 37, and alternately switch and connect the fixed phase shifter 53 and the bypass 54 between the input terminal and the output terminal.

For example, a high-frequency cable having a length L is used as the bypass 54, and a high-frequency cable having a length L + λ / 2 is used as the fixed phase shifter 53, for example. That is, the fixed phase shifter 53 uses a high-frequency cable that is longer by a half wavelength than the side path 54, and is set so that the input signal is delayed by 180 electrical degrees compared to the side path 54.

On the other hand, the sub phase shifter control circuit 37 includes a pulse oscillator 56, a flip-flop (bistable multivibrator) 57, and first and second switch driving circuits 58 and 59.
The control signal (alarm signal) provided from the cancellation control unit 40 is input to the pulse oscillator 56. The pulse oscillator 56 is an oscillator having a low frequency of, for example, 0.1 to several Hz and oscillates only while a control signal (alarm signal) is given from the cancellation control unit 40. Input to the trigger terminal T. The flip-flop 57 performs an inversion operation every time a pulse signal is supplied from the pulse oscillator 56, and alternately outputs a “1” signal from a Q-side terminal and a Q′-side terminal (an inversion terminal of Q). The switch driving circuits 58 and 59 switch the switches 51 and 52 each time the flip-flop 57 performs the inverting operation, and select the fixed phase shifter 53 or the bypass 54.

FIG. 3 shows a specific circuit configuration example of the sub phase shifter 36. The input terminal t1 of the sub phase shifter 36 is connected to the cathodes of the diodes D1 and D3 constituting the switch 51 via the capacitor C1, and is further grounded via the resistor R1. The diode D1
The drive current I1 is supplied from the first switch drive circuit 58 via the high-frequency coil L1 to the anodes. The drive current I1 is supplied to the diode D via the fixed phase shifter 53.
2 is also supplied.

The anodes of the diodes D1 and D3 are connected to the anodes of the diodes D2 and D4 constituting the switch 52 via a fixed phase shifter 53 and a bypass 54, respectively. The drive current I2 is supplied to the anode of the diode D4 from the second switch drive circuit 59 via the high-frequency coil L2. This drive current I2 is
4 is also supplied to the diode D3. The cathodes of the diodes D2 and D4 are grounded via a resistor R2, and further connected to an output terminal t2 via a capacitor C2.

The sub phase shifter 36 configured as described above is
When a "1" signal is output from the Q-side output terminal of the flip-flop 57 of the sub-phase shifter control circuit 37 shown in FIG. 2, the drive current I1 is supplied from the first switch drive circuit 58, and the diode D1 D2 is biased in the forward direction and becomes conductive.

On the other hand, the second switch drive circuit 59 receives the "0" signal from the flip-flop 57 and enters a non-operating state, sets the drive current I2 to "0" and holds it at the ground level. At this time, the current flowing from the diodes D1 and D2 to the resistors R1 and R2 causes the resistors R1 and R2 to change.
2 causes a voltage drop and applies a reverse bias to the diodes D3 and D4, so that these diodes D3 and D4 are turned off. As a result, the fixed phase shifter 53 is connected between the input terminals t1 and t2, and the bypass 54 is disconnected.

Next, the flip-flop 57 is inverted and Q
When a “0” signal is output from the output terminal on the side and a “1” signal is output from the output terminal on the Q ′ side, the first switch drive circuit 58 is in a non-operation state, and the second switch drive circuit 59 is in an operation state. As a result, the drive current I2 is output from the second switch drive circuit 59.
Is supplied, and the diodes D3 and D4 are biased in the forward direction and become conductive.

On the other hand, the first switch drive circuit 58 becomes inactive as described above, and the drive current I1 is set to "0".
And hold at the ground level. At this time, the current flowing from the diodes D3 and D4 to the resistors R1 and R2 causes a voltage drop in the resistors R1 and R2, and the diode D3
Since a reverse bias is applied to D1 and D2, these diodes D1 and D2 are turned off. As a result, the input terminal t
The bypass 54 is connected between 1 and t2, and the fixed phase shifter 53 is in a disconnected state. As described above, each time the flip-flop 57 performs the inverting operation, the fixed phase shifter 53 and the bypass 54 are alternately selected.

Next, the overall operation of the interference wave removing device 30 will be described. In FIG. 1, a signal of frequency f1 output from a transmitter 1 is sent to a transmission antenna 3 via a directional coupler 31 of an interference wave canceller 30, and is transmitted from the transmission antenna 3 to the outside. The radio wave transmitted from the outside is received by the receiving antenna 4 and is supplied to the directional coupler 32.
The signal is input to the receiver 2 via the directional coupler 33.
The receiver 2 receives a radio wave having a frequency close to the transmission frequency f1, for example, a frequency f2 which is an adjacent channel. At this time, a part of the radio wave transmitted from the transmission antenna 3 goes around to the reception antenna 4 and becomes an interference wave for the reception wave of the frequency f2.

On the other hand, the interference wave removing device 30 branches a part of the output signal of the transmitter 1 as a canceling signal by the directional coupler 31, and the variable attenuator 34, the variable phase shifter 35 and the sub phase shifter 36 Is input to the directional coupler 32 on the receiving side.
At this time, the monitor receiver 38 monitors the sneak interference wave of the frequency f1, and when the sneak interference wave is detected,
The detection signal is input to the cancellation control unit 40 via the A / D converter 39.

The cancellation control unit 40 controls the attenuation of the variable attenuator 34 and the variable phase shifter 35 in accordance with the level and the phase of the sneaking wave monitored by the monitor receiver 38.
Is controlled so that the sneak interference signal monitored by the monitor receiver 38 is minimized. That is,
The cancellation control unit 40 receives the directional coupler 32 from the directional coupler 31 via the variable attenuator 34, the variable phase shifter 35, and the sub-phase shifter 36, for the interfering wave going from the transmission antenna 3 to the reception antenna 4. The variable attenuator 34 and the variable phase shifter 35 are controlled so that the levels of the canceling signals input to are the same and the phases are different by 180 °, and the sneaking interference wave is removed.

In the above-described control operation, the cancellation control section 40 determines that the phase change between the transmitting antenna 3 and the receiving antenna 4 is within the adjustment range of the variable phase shifter 35 (about 0 ° to 240 °).
, The cancellation condition is no longer satisfied, and a control signal (alarm signal) is output to the sub phase shifter control circuit 37. That is, the canceling control unit 40 controls the variable attenuator 34
No matter how the variable phase shifter 35 is adjusted, it is determined that the output of the monitor receiver 38 does not drop below a predetermined value, and a control signal (alarm signal) is output to the sub phase shifter control circuit 37. I do.

When a control signal (alarm signal) is given from the cancellation control unit 40, the sub-phase shifter control circuit 37 operates the pulse oscillator 56 to generate a pulse signal as described above, and inverts the flip-flop 57. Let it. As a result, the switch driving circuits 58 and 59 operate to operate the switch 5.
1 and 52 are switched, and either the fixed phase shifter 53 or the bypass 54 is selected.

Since the phase between the input and output terminals changes by 180 ° when the fixed phase shifter 53 or the bypass 54 is selected, the sub phase shifter 36 adjusts the adjustable range of the variable phase shifter 35 (approximately (0 ° to 240 °), the phase of 0 ° to 400 ° or more can be adjusted, and any phase change can be handled.

Therefore, when the switches 51 and 52 of the sub phase shifter 36 are switched via the sub phase shifter control circuit 37 by the control signal (alarm signal) output from the cancellation control unit 40, the phase condition is always changed. Since the satisfaction is satisfied, the cancellation control by the cancellation control unit 40 is established before the next pulse signal is output from the pulse oscillator 56. As a result, the control signal (alarm signal) from the cancellation control unit 40 is output.
Is no longer output, so that the sub phase shifter 36 maintains its state.

According to the first embodiment, even if the amount of phase adjustment changes significantly due to a change in environment, etc.
By switching the phase shift amount of the sub phase shifter 36, the phase adjustment can be reliably performed without deteriorating the suppression performance of the interference wave removal.

In the first embodiment, the sub phase shifter 3
6 shows a case in which one fixed phase shifter having a phase shift of 180 ° is provided, but a plurality of fixed phase shifters may be provided to finely switch the phase shift. In this case, the amount of adjustment of the variable phase shifter 35 is small, and the matching can be performed more accurately. Further, in the above-described embodiment, the case where one sub phase shifter 36 is provided has been described, but a plurality of sub phase shifters 36 may be provided for switching.

(Second Embodiment) Next, a second embodiment of the present invention will be described. In the second embodiment, the sub-attenuator 61 and the sub-attenuator 61 shown in FIG. 4 are used instead of the sub-phase shifter 36 and the sub-phase shifter control circuit 37 in the interference wave canceling device according to the first embodiment shown in FIG. An attenuator control circuit 62 is provided. Since other configurations are the same as those of the first embodiment shown in FIG. 1, the sub-attenuator 61 and the sub-attenuator control circuit 62 will be described. In the second embodiment,
The variable phase shifter 35 has sufficient margin for phase adjustment. When the coupling attenuation between the transmitting antenna 3 and the receiving antenna 4 deviates from the adjustment range (0 to 15 dB) of the variable attenuator 34, the cancellation control unit 40 sub-attenuates the control signal (alarm signal). Output to the device control circuit 62.

The sub-attenuator 61 is provided with switches 71 and 72 at an input terminal and an output terminal, respectively.
A fixed attenuator 73 and a bypass 74 are provided between 72. That is, the contact a1 of the switch 71 and the contact a of the switch 72
2, a fixed attenuator 73 is connected, and a bypass 74 is connected between a contact b1 of the switch 71 and a contact b2 of the switch 72. The switches 71 and 72 operate in synchronization with a signal from the sub-attenuator control circuit 62, and alternately switch and connect the fixed attenuator 73 and the bypass 74 between the input terminal and the output terminal.

The fixed attenuator 73 is set to an attenuation of slightly less than 15 dB, for example, slightly smaller than the adjustment range of the variable attenuator 34. A high-frequency cable having a length D is used as the bypass 74, and its attenuation is zero. The length D of the high-frequency cable is set in accordance with the amount of phase change when a signal passes through the fixed attenuator 73, that is, the same amount of phase change occurs between the fixed attenuator 73 and the bypass 74.

On the other hand, the sub-attenuator control circuit 62 includes a pulse oscillator 76, a flip-flop (bistable multivibrator) 77, first and second switch driving circuits 78 and 79.
And a control signal (alarm signal) provided from the cancellation control unit 40 is input to the pulse oscillator 76. Each time a control signal (alarm signal) is supplied from the cancellation control unit 40, the sub-attenuator control circuit 62
Of the sub-phase shifter control circuit 37 in the first embodiment.

In the above configuration, the cancellation control unit 40
When the coupling attenuation between the transmitting antenna 3 and the receiving antenna 4 deviates from the adjustment range (0 to 15 dB) of the variable attenuator 34, the canceling condition is not satisfied, and the control signal (alarm signal) is transmitted to the sub-attenuator. Output to the control circuit 62.

When a control signal (alarm signal) is given from the cancellation control unit 40, the sub-attenuator control circuit 62 operates the pulse oscillator 76 to generate a pulse signal.
The flip-flop 77 is inverted. As a result, the switch drive circuits 78 and 79 operate to switch the switches 71 and 72, and select one of the fixed attenuator 73 and the bypass 74.

In the sub-attenuator 61, when the fixed attenuator 73 or the bypass 74 is selected, the amount of attenuation between the input and output ends changes slightly less than 15 dB. Therefore, the adjustment range of the variable attenuator 34 (about 15 dB). When combined with, the attenuation amount of approximately 30 dB can be adjusted, and the adjustment range can be greatly expanded.

According to the second embodiment, even if the amount of attenuation adjustment changes significantly due to a change in environment, etc.,
By switching the attenuation amount of the sub-attenuator 61, the attenuation amount can be surely adjusted without deteriorating the suppression performance of the interference wave removal.

In the second embodiment, the sub-attenuator 6
Although the case where one fixed attenuator 73 is provided as 1 has been described, a plurality of fixed attenuators may be provided to switch finely. Further, in the second embodiment, the case where one sub-attenuator 61 is provided is described, but a plurality of sub-attenuators 61 may be provided for switching.

(Third Embodiment) Next, a third embodiment of the present invention will be described. In the third embodiment, an interference wave removing device is configured by combining the first embodiment and the second embodiment. That is, the third embodiment is different from the first embodiment in that the sub phase shifter 3 shown in FIG.
The sub-attenuator 61 and the sub-attenuator control circuit 62 are provided after the sub-attenuator 6 and the sub-phase shifter control circuit 37. This third
In the embodiment, the cancellation control unit 40 includes the transmitting antenna 3
When the phase change between the transmission antenna 3 and the reception antenna 4 deviates from the adjustment range (about 0 ° to 240 °) of the variable phase shifter 35, and the coupling attenuation between the transmission antenna 3 and the reception antenna 4 is variable attenuation When it deviates from the adjustment range (approximately 0 to 15 dB) of the shifter 34, it outputs a control signal (alarm signal) to the sub phase shifter control circuit 37.

The sub phase shifter 36 and the sub attenuator 61 have the same configuration as those shown in the first and second embodiments.
On the other hand, the sub phase shifter control circuit 37 and the sub attenuator control circuit 62 are provided with a pulse oscillator 56 only in the sub phase shifter control circuit 37, for example. It is input to the trigger terminal T of the flip-flop 77 of the attenuator control circuit 62. In other words, the two flip-flops 57 and 77 generate two-bit 2 bits.
And a flip-flop 77 each time a pulse signal is output from the Q-side terminal of the flip-flop 57.
Operates in reverse. Therefore, there are four possible states of this binary counter, "00, 01, 10, 11", and accordingly, the switches 51 and 52 of the sub-phase shifter 36 and the switches 71 and 52 of the sub-attenuator 61, 72 is switched. By switching the switches 51, 52, 71 and 72, the fixed phase shifter 53 and the bypass 54 of the sub phase shifter 36 and the fixed attenuator 73 and the bypass 74 of the sub attenuator 61 are selected in the following combinations. You.

(1) Fixed phase shifter 53 and side path 74 (2) Side path 54 and side path 74 (3) Fixed phase shifter 53 and fixed attenuator 73 (4) Side path 54 and fixed attenuator 73 The phase shifter 36 and the sub-attenuator 61
Each time a control signal (alarm signal) is output from, the fixed phase shifter 53 and the fixed attenuator 73 are selectively controlled in the above-described order to adjust the phase and the amount of attenuation. The phase can correspond to all of “0 ° to 360 °”, and the attenuation can be adjusted to about 5.5 times the conventional adjustment width.

Therefore, according to the third embodiment, even if the amount of phase adjustment and the amount of attenuation adjustment change significantly due to a change in the environment or the like, the suppression performance of interference wave removal is not deteriorated, Adjustment and adjustment of the amount of attenuation can be reliably performed.

In the third embodiment, the sub phase shifter 3
6 shows the case where the sub-attenuator 61 is provided at the subsequent stage, but the same effect can be obtained even if the positions of the sub-phase shifter 36 and the sub-attenuator 61 are exchanged.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described. This fourth embodiment uses the control voltage of the variable phase shifter 35 instead of the control signal (alarm signal) output from the cancellation control unit 40 as shown in FIG. Is performed. That is, the control voltage supplied from the cancellation control unit 40 to the variable phase shifter 35 via the D / A converter 42 is input to the window comparator 81. Further, an upper limit setting voltage indicating the upper limit of the control voltage and a lower limit setting voltage indicating the lower limit of the control voltage in the variable phase shifter 35 are supplied to the window comparator 81 from a control unit (not shown).

The window comparator 81 has a D / A
It monitors whether the control voltage of the variable phase shifter 35 output from the converter 42 is within the range of the upper limit set voltage and the lower limit set voltage, and when the control voltage is out of the range of the upper limit set voltage and the lower limit set voltage, This state is detected, and a detection signal is output to the sub phase shifter control circuit 37. The sub phase shifter control circuit 37
When a detection signal is given from the window comparator 81, the pulse oscillator 56 operates and outputs a pulse signal,
The switches 51 and 52 of the sub phase shifter 36 are switched by inverting the flip-flop 57.

Hereinafter, similarly, the window comparator 8
1 each time a detection signal is output from the sub phase shifter control circuit 37
The switches 51 and 52 of the sub phase shifter 36 are changed over, and the fixed phase shifter 53 and the bypass 54 are alternately selected. Therefore, no matter how the phase between the transmitting antenna 3 and the receiving antenna 4 changes, it is possible to reliably cope with the same as in the above-described embodiments.

According to the fourth embodiment, even if the cancellation control unit 40 does not have a function of outputting a control signal (alarm signal), the cancellation control unit 40
The switching control of the sub phase shifter 36 can be performed using the control voltage of the variable phase shifter 35 output via the / A converter 42.

In the fourth embodiment, the sub phase shifter 3
6 has been described, the sub-attenuator 6
In the case where the switching control is performed, the canceling controller 4
By monitoring the control voltage supplied from 0 to the variable attenuator 34 via the D / A converter 41 with a window comparator, the present invention can be similarly implemented.

In the case where both the sub-phase shifter 36 and the sub-attenuator 61 are provided as shown in the third embodiment, the variable attenuation is provided from the cancellation controller 40 via the D / A converters 41 and 42. By monitoring the control voltages supplied to the phase shifter 34 and the variable phase shifter 35 with window comparators, respectively, the present embodiment can be implemented in the same manner as in the fourth embodiment. Further, the sub phase shifter control circuit 37 and the sub attenuator control circuit 62 in each of the above embodiments may be configured by a microcontroller simulating this.

[0068]

As described above in detail, according to the present invention, a variable attenuator and an antenna for adjusting a coupling attenuation amount between antennas in an interference wave elimination apparatus for removing a sneak interference wave from a transmitting antenna to a receiving antenna. A variable phase shifter for adjusting the phase change between the antennas, a sub phase shifter is provided, and the phase shift amount of the sub phase shifter is switched when the phase change between the antennas deviates from the adjustment range of the variable phase shifter. Therefore, the phase adjustment range can be widened, and even if the amount of phase adjustment changes significantly due to changes in the environment, etc., it is necessary to take measures without deteriorating the suppression performance of interference wave removal. Can be.

Further, according to the present invention, a sub-attenuator is provided together with the variable attenuator, and the attenuation of the sub-attenuator is switched when the coupling attenuation between the antennas is out of the adjustment range of the variable attenuator. Therefore, the adjustment range can be widened, and even if the coupling attenuation between antennas changes significantly due to changes in the environment, etc., the attenuation should be adjusted without deteriorating the suppression performance of interference wave removal. Can be.

The present invention further comprises a cancellation control unit for adjusting the variable attenuator and the variable phase shifter, and outputs a signal when the variable attenuator or the variable phase shifter deviates from the adjustment range from the cancellation control unit. Since the switching control of the sub phase shifter, the sub attenuator, and the like is performed using the control signal (alarm signal), the switching of the sub phase shifter and the sub attenuator can be reliably performed.

Further, according to the present invention, the control voltage output from the cancellation control section to the variable attenuator and the variable phase shifter is monitored, and the control voltage of the variable attenuator or the variable phase shifter is monitored. When the voltage exceeds the upper limit set voltage and the lower limit set voltage, the state is detected and the sub phase shifter and the sub attenuator are switched and controlled, so that the cancellation control unit outputs a control signal (alarm signal). , The switching between the sub phase shifter and the sub attenuator can be reliably performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of an interference wave removing apparatus according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram showing details of a sub phase shifter and a sub phase shifter control circuit in the embodiment.

FIG. 3 is a view showing a specific configuration example of a sub phase shifter in the embodiment.

FIG. 4 is a configuration diagram of a sub-attenuator and a sub-attenuator control circuit according to a second embodiment of the present invention.

FIG. 5 is a configuration diagram of a sub phase shifter and a sub attenuator according to a third embodiment of the present invention.

FIG. 6 is a diagram showing a main part of an interference wave removing apparatus according to a fourth embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a conventional interference wave removing device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 3 transmitting antenna 4 receiving antenna 30 interference wave canceller 31, 32, 33 directional coupler 34 variable attenuator 35 variable phase shifter 36 subphase shifter 37 subphase shifter control circuit 38 monitor receiver 39 A / D conversion Device 40 Cancellation control unit 41, 42 D / A converter 51, 52 Switch 53 Fixed phase shifter 54 Bypass 56 Pulse oscillator 57 Flip-flop 58 First switch drive circuit 59 Second switch drive circuit 61 Secondary attenuator 62 Sub attenuator control circuit 71, 72 Switch 73 Fixed attenuator 74 Bypass 76 Pulse oscillator 77 Flip-flop 78 First switch drive circuit 79 Second switch drive circuit 81 Window comparator

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Susumu Nakabayashi 4-72 Miyagaya Tower, Omiya City, Saitama Prefecture Inside Antena Giken Co., Ltd. (72) Inventor Tokoki Oba 4 Miyagaya Tower, Omiya City, Saitama Prefecture F-term (reference) at address Chome 72 Antenna Giken Co., Ltd.

Claims (10)

[Claims] An interfering wave removing apparatus for removing an interfering wave from a transmitter via a transmitting antenna and a receiving antenna disposed close to the transmitting antenna, the transmitting signal transmitted from the transmitter to the transmitting antenna being partially transmitted. Signal extracting means for extracting as an interference wave canceling signal, a variable attenuator for adjusting the level of the canceling signal extracted by the extracting means, a variable phase shifter for adjusting the phase of the canceling signal, and a variable phase shifter And at least one sub-phase shifter comprising a fixed phase shifter and a bypass provided in series with the variable attenuator, the variable phase shifter, and the cancellation signal adjusted by the sub-phase shifter. Coupling means for combining with a signal and canceling out an interference wave circulating from the transmitting antenna to the receiving antenna, and a signal input to the receiver via the coupling means A monitor receiver that monitors the sneak interference wave, and a cancellation control unit that controls the amount of attenuation of the variable attenuator and the amount of phase shift of the variable phase shifter according to the sneak interference wave monitored by the monitor receiver. A phase change deviation detecting means for detecting a state in which a phase change between the transmitting antenna and the receiving antenna deviates from the adjustment range of the variable phase shifter, and a deviation detecting signal output from the phase change deviation detecting means. An interfering wave removing apparatus comprising: a sub phase shifter control means for switching between a fixed phase shifter and a bypass in the sub phase shifter. 2. An interfering wave removing apparatus for removing an interfering wave from a transmitter via a transmitting antenna and a receiving antenna arranged in close proximity to the receiver, wherein a part of a transmitting signal sent from the transmitter to the transmitting antenna is removed. Signal extracting means for extracting as an interference wave canceling signal, a variable attenuator for adjusting the level of the canceling signal extracted by the extracting means, a variable phase shifter for adjusting the phase of the canceling signal, and a variable attenuator. And at least one sub-attenuator comprising a fixed attenuator and a bypass provided in series with the variable attenuator, the sub-attenuator, and the cancellation signal adjusted by the variable phase shifter are combined with the reception signal of the reception antenna. Coupling means for canceling an interfering wave from the transmitting antenna to the receiving antenna, and a signal inputted to the receiver via the coupling means. A monitor receiver for monitoring the sneak interference in the signal, and a canceling control for controlling the attenuation of the variable attenuator and the phase shift of the variable phase shifter in accordance with the sneak interference monitored by the monitor receiver. Unit, an attenuation departure detecting means for detecting a state in which a coupling attenuation amount between the transmitting antenna and the receiving antenna deviates from the adjustment range of the variable attenuator, and a departure detection output from the attenuation deviating detecting means. An interfering wave removing device comprising: a sub-attenuator control means for switching between a fixed attenuator and a bypass in the sub-attenuator according to a signal. 3. An interfering wave removing apparatus for removing an interfering wave from a transmitter via a transmitting antenna and a receiving antenna arranged close to the transmitting antenna, wherein a part of a transmitting signal transmitted from the transmitter to the transmitting antenna is removed. Signal extracting means for extracting as an interference wave canceling signal, a variable attenuator for adjusting the level of the canceling signal extracted by the extracting means, a variable phase shifter for adjusting the phase of the canceling signal, and a variable phase shifter At least one sub-phase shifter comprising a fixed phase shifter and a side path provided in series with respect to the variable attenuator; and at least one sub-attenuator comprising a fixed attenuator and a side path provided in series with the variable attenuator. Combining the cancellation signal adjusted by the variable attenuator, the variable phase shifter, and the sub-phase shifter with the reception signal of the reception antenna, and receiving the reception signal from the transmission antenna. Coupling means for canceling an interfering wave wrapping around the antenna, a monitor receiver for monitoring the sneaking interference wave in a signal input to the receiver via the coupling means, and a sneaking interference wave monitored by the monitor receiver And a cancellation control unit that controls the amount of attenuation of the variable attenuator and the amount of phase shift of the variable phase shifter according to the phase change between the transmission antenna and the reception antenna deviates from the adjustment range of the variable phase shifter. Phase change deviation detection means for detecting the state of the phase change deviation detection means, a sub phase shifter control means for switching between the fixed phase shifter and the bypass in the sub phase shifter by a deviation detection signal output from the phase change deviation detection means,
Attenuation departure detection means for detecting a state in which the coupling attenuation between the transmission antenna and the reception antenna deviates from the adjustment range of the variable attenuator, and a departure detection signal output from the attenuation departure detection means. An interfering wave removing apparatus, comprising: a sub-attenuator control means for switching between a fixed attenuator and a side path in the sub-attenuator. 4. The apparatus according to claim 1, wherein the sub phase shifter comprises a fixed phase shifter divided into a plurality of parts. 5. The apparatus according to claim 1, wherein the phase change deviation detecting means is provided in a cancellation control unit. 6. The apparatus according to claim 1, wherein the attenuation deviation detecting means is provided in a cancellation control unit. 7. The phase change deviation detecting means comprises a window comparator that compares a control voltage supplied from the cancellation control unit to the variable phase shifter with an upper limit set voltage and a lower limit set voltage and outputs a departure detection signal. The interference wave canceling device according to claim 1, 2, or 3. 8. The attenuation amount deviation detecting means is configured by a window comparator that compares a control voltage supplied from the cancellation control unit to the variable attenuator with an upper limit setting voltage and a lower limit setting voltage and outputs a deviation detection signal. The interference wave removing apparatus according to claim 1, 2, or 3. 9. The sub-phase shifter control means includes: a pulse oscillator whose operation is controlled by a deviation detection signal output from the phase change deviation detection means; and a flip-flop that inverts operation by a pulse signal output from the pulse oscillator. 4. An interfering wave according to claim 1, further comprising switching control means for switching between a fixed phase shifter and a bypass of said sub phase shifter based on an output signal of said flip-flop. Removal device. 10. The sub-attenuator control means includes a pulse oscillator whose operation is controlled by a departure detection signal output from the attenuation departure detection means, and a flip-flop that inverts operation by a pulse signal output from the pulse oscillator. 4. The apparatus according to claim 1, further comprising switching control means for switching between a fixed attenuator and a bypass of the sub-attenuator based on an output signal of the flip-flop.