JP2022164302A - amplifier - Google Patents

Abstract

To provide a technique for suppressing unnecessary radiation from an amplification device using a carrier control method.SOLUTION: An amplification device includes an amplification circuit that amplifies an input signal, an amplitude limiting circuit that limits the amplitude of the input signal, a switching circuit that switches connection between a path via the amplification circuit and a path via the amplitude limiting circuit, and a switching control circuit that detects the input signal and controls the switching circuit to switch connection from a path via the amplitude limiting circuit to a path via the amplification circuit when the input signal is detected.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD The present invention relates to an amplifier, and more particularly to an amplifier used in wireless communication.

A wireless communication device with relatively low transmission power may be provided with an external amplifier that amplifies the transmission power. The amplification device amplifies the transmission signal output from the wireless communication device when the wireless communication device is transmitting with the amplifier circuit inside the amplification device and transmits it to the antenna, and when the wireless communication device is receiving, the received signal is received by the antenna. The signal must be transmitted to the radio through a roundabout circuit of the amplifier circuit. Therefore, it is necessary to switch the path in the amplifier in conjunction with the transmission and reception of the wireless communication device.

Using a power amplifier having a signal path switching function, the output level of the transmitter required at the time of transmission is a level that requires a power amplifier and a level that does not require a power amplifier. A technique is disclosed that also switches the power supply by the circuit. (See Patent Document 1). However, when an amplifier for amplifying transmission power is provided externally, a separate control line is required for switching paths within the amplifier in conjunction with transmission and reception of the wireless communication device. In addition, as a method of switching the path in the amplifier in conjunction with the transmission and reception of the wireless communication device, there is a method called carrier control in which the transmission signal from the wireless communication device is detected in the amplifier and the path in the amplifier is switched. exist from the past.

JP-A-11-308125

However, when changing the path in the amplifier device using the technique described in Patent Document 1, a separate control signal cable for controlling the amplifier device from the wireless communication device is required in addition to the coaxial cable for transmitting the wireless signal. . Further, in the carrier control method described above, when changing the path in the amplifier, the control signal cable for controlling the amplifier from the wireless communication device is not required. There is a problem that unnecessary radiation occurs due to momentary interruption of the signal before switching to transmission via the amplifier of the device.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a technique for suppressing unwanted radiation in an amplifier using a carrier control method.

In order to solve the above problems, an amplifier device according to one aspect of the present invention includes an amplifier circuit that amplifies an input signal, an amplitude limiting circuit that limits the amplitude of the input signal, a path through the amplifier circuit and the amplitude. a switching circuit that switches connection with a path through the amplitude limiting circuit; and a switching circuit that detects the input signal and, when the input signal is detected, switches the amplifier circuit from the path through the amplitude limiting circuit to the switching circuit. and a switching control circuit that controls switching of connection to a path through the network.

Any combination of the above constituent elements, and any conversion of expressions of the present invention into methods, devices, systems, recording media, computer programs, etc. are also effective as embodiments of the present invention.

According to the present invention, it is possible to provide a technique for suppressing unwanted radiation from an amplifier using a carrier control method.

1 is a schematic diagram of wireless communication equipment to which the amplifying device of the present invention is connected; FIG. 1 is a configuration diagram of a carrier control type amplifier circuit; FIG. 1 is a configuration diagram of an amplifier device of the present invention; FIG. 3 is a configuration diagram of an amplitude limiting circuit in the amplifying device of the present invention; FIG. 4 is a time chart of signals of each part of the amplifier device of the present invention; FIG. 2 is a configuration diagram of a second embodiment of the amplifying device of the present invention; FIG. 3 is a configuration diagram of Embodiment 3 of the amplifying device of the present invention; FIG. 10 is a configuration diagram of an amplitude limiting circuit in Embodiment 3 of the amplifying device of the present invention; FIG. 11 is a configuration diagram of a modification of the amplitude limiting circuit in Embodiment 3 of the amplifying device of the present invention;

The present invention will now be described with reference to the accompanying drawings. FIG. 1 is a schematic diagram of wireless communication equipment to which an amplifier is connected. A wireless communication device 100 includes a wireless communication device 1 , an amplifier device 2 , and an antenna 3 .

In the wireless communication equipment 100, the transmission/reception connector of the wireless communication device 1 and the connector (input terminal) of the amplifier device 2 are connected with a coaxial cable, and the connector (output terminal) of the amplifier device 2 and the connector of the antenna 3 are connected with a coaxial cable. It is In addition to this, it has a power supply section (not shown), which supplies necessary power to the wireless communication device 1 and the amplifier device 2 . It should be noted that the notations of input and output such as input terminals and output terminals are definitions for the directions of transmission signals.

The wireless communication device 1 is a transceiver that transmits and receives radio frequency waves to communicate various information such as voice, images, and positional information. Although the figure shows a portable transceiver, it may be a vehicle-mounted transceiver or an indoor transceiver.

The amplifier device 2 is a device for increasing the transmission output of the wireless communication equipment 100 to be greater than the transmission output of the wireless communication device 1 alone. Specifically, the amplifier 2 is a device that amplifies the transmission signal of the wireless communication device 1 and supplies it to the antenna 3 . Further, the amplifier device 2 has a function of transmitting a received signal transmitted from the antenna 3 to the wireless communication device 1 . Further, the amplifier device 2 may have a function of supplying the transmission signal of the wireless communication device 1 to the antenna 3 without amplifying it.

The antenna 3 outputs the transmission signal supplied from the amplifier 2 as radio waves. Also, the antenna 3 converts the received radio wave into a received signal.

The amplifier device 2 will be described with reference to FIG. FIG. 2 is a block diagram of the amplifier 2. As shown in FIG. The amplifier device 2 includes an amplifier circuit 20 , a detour circuit 21 , a switching circuit 22 ( 221 and 222 ), and a switching control circuit 23 . The amplifier circuit 20 is an amplifier for amplifying the transmission output signal of the wireless communication device 1 to make the transmission output greater than the transmission output of the wireless communication device 1 . For example, if the transmission output of the wireless communication device 1 is 5W, the amplifier circuit 20 amplifies the transmission signal of the wireless communication device 1 to 20W.

The bypass circuit 21 is a path for transmitting the signal received from the antenna 3 to the wireless communication device 1 . In addition, the detour circuit 21 may be a path that bypasses the amplifier when the transmission signal is not required to be amplified by the amplifier circuit 20 of the amplifier device 2, that is, when the transmission output of the wireless communication device 1 is output from the antenna 3. .

The switching circuit 22 includes an input-side switching circuit 221 for switching between the amplifier circuit 20 and the bypass circuit 21 for the input terminal C1, and an output-side switching circuit 221 for switching between the amplifier circuit 20 and the bypass circuit 21 for the output terminal C2. and a switching circuit 222 . The switching circuit 221 on the input side switches between supplying the transmission signal output from the wireless communication device 1 to the amplifier circuit 20 and the detour circuit 21 . The switching circuit 222 on the output side switches between supplying the transmission signal amplified by the amplifier circuit 20 to the antenna and transmitting the transmission signal of the wireless communication device 1 transmitted via the detour circuit 21 to the antenna 3. . In addition, the input side switching circuit 221 and the output side switching circuit 222 connect the wireless communication device 1 and the antenna 3 via the detour circuit 21 when transmitting the signal received from the antenna 3 to the wireless communication device 1. . Hereinafter, the switching destination of the switching circuit 22 will be referred to as the amplifier circuit side or the detour circuit side.

The switching control unit 23 detects a transmission signal output from the wireless communication device 10, and switches the switching circuit 22 to the amplifier circuit side when the transmission signal is detected. That is, the amplifier 2 switches between transmission and reception in the amplifier 2 by a carrier control method. In the above description, "detection of transmission signal" is used. However, since it is meaningless to carry only a carrier wave (carrier) in the transmission signal during the time required for signal detection, it is sometimes described as "detection of carrier" hereinafter. They have the same meaning. "Receiving" means a state of receiving a signal, and strictly speaking, a state of not receiving a signal is "standby", but unless otherwise specified, "receiving" is used.

In the carrier control method, the carrier of the wireless communication device 1 is used to switch the path of the amplifier device 2 from the detour circuit side to the amplifier circuit side. Specifically, the carrier control method detects and rectifies part of the carrier transmitted from the wireless communication device 1 to obtain a DC voltage corresponding to the level of the carrier. Furthermore, the carrier control method switches the switching circuit 21 to the amplifier circuit side when the obtained DC voltage exceeds a predetermined value. Note that the carrier control method is a well-known technology.

The carrier control method does not require a control signal cable for controlling the amplification device 2 from the wireless communication device 1 when changing the path or operation corresponding to transmission and reception in the amplification device 2, but as follows. phenomenon occurs.

(1) The transmission signal is supplied to the antenna via the detour circuit 21 that bypasses the amplifier circuit 20 during the time until the transmission signal from the wireless communication device 1 is detected,
(2) Furthermore, while the transmission signal from the wireless communication device 1 is being supplied to the antenna 3 via the detour circuit 21, the switching control circuit 23 detects the transmission signal and the switching circuit 22 operates. Once the path of the transmission signal is released from the detour circuit 21,
(3) After that, the switching operation of the switching circuit 22 is completed, the transmission signal from the wireless communication device 1 is supplied to the amplification circuit 20, and the transmission signal amplified by the amplification circuit 20 is routed to the antenna 3. Because of the switching, the transmission signal supplied to the antenna 3 is interrupted while the switching circuit 22 switches from the detour circuit 21 to the amplifier circuit 20 . That is, the transmission signal is momentarily interrupted in the process of starting transmission.

As a result, the transmission signal is momentarily interrupted during the period from when the wireless communication device 1 starts transmission until it switches to transmission via the amplifier circuit of the amplifier device 2, and unnecessary radiation is generated due to the momentary interruption of the transmission signal. I had a problem.

The unnecessary radiation described above occurs over a wide band due to the unnecessary radiation caused by the momentary interruption of the signal. Further, the level of unwanted radiation increases as the power supplied to the antenna 3 immediately before and after the momentary interruption increases. Therefore, in order to suppress unnecessary radiation at the start of transmission, it is necessary to reduce the power supplied to the antenna 3 before and after the instantaneous interruption. Techniques for suppressing unnecessary radiation in switching by the carrier control method will be described below according to a plurality of embodiments.

(Embodiment 1)
An amplifier device 20 according to Embodiment 1 of the present invention will be described with reference to FIG. FIG. 3 is a configuration diagram of the amplifier device 20. As shown in FIG. In contrast to the amplifier 20 described above with reference to FIG. Prepare.

The amplifying device 2 switches between a transmission state and a standby state by a carrier control method. A carrier from the wireless communication device 1 is detected, and the path in the amplifier 2 is switched to a transmission path for amplifying the transmission signal by the amplification circuit 20 and outputting it. That is, the switching control circuit 23 detects the carrier, and the switching control circuit 23 outputs to the switching circuit 22 a path switching signal for switching the path from the amplitude limiting circuit 24 (detour path) to the amplifier circuit 20 (amplification path). The amplifying device 20 shifts to the transmission operation from the rise of the path switching signal. When the output of the path switching signal is started, the amplification device 2 controls the amplification degree of the amplification circuit 20 by the amplification control circuit 25, and then gradually increases the amplification degree of the amplification circuit 20 by the amplification control circuit 25 to reach a predetermined level. A transmission signal is output while controlling the amplification to reach a normal level over time.

The amplitude limiting circuit 24 is a bypass path for the amplifier circuit 20 and limits the amplitude of the signal transmitted between the input side switching circuit 221 and the output side switching circuit 222 . Specifically, the amplitude limiting circuit 24 includes an amplitude limiting element that limits the amplitude of the signal transmitted to the transmission path as shown in FIG. The amplitude limiting element is, for example, a bidirectional diode, interposed between the bidirectional diode and the ground potential. The voltage swing of the transmitted signal is thus limited by the forward voltage of the diode. The amplitude limiting element may be arranged by changing the direction of the two diodes, and it is desirable that the characteristics are the same. Further, the amplitude limiting circuit 24 transmits the reception signal received by the antenna 3 to the wireless communication device 1 when the wireless communication device 1 is in the reception state. Since the voltage amplitude of the received signal is much smaller than the amplitude voltage limited by the amplitude limiting circuit 24 of the amplitude limiting circuit 24, there is no problem for the wireless communication device 1 to perform reception via the amplitude limiting circuit 24.

The amplification control circuit 25 controls the amplification degree of the amplification circuit 20 for a predetermined time from the start of transmission. Therefore, the amplifier circuit 20 has a gain control function that can change the degree of amplification according to a predetermined signal. The amplification control circuit 25 outputs an amplification degree control signal for changing the amplification degree to the amplification circuit 20 .

In describing in detail the operation of the amplifier 20 according to the first embodiment of the present invention for suppressing unnecessary radiation in switching by the carrier control method, FIG. Explain signal changes. FIG. 5 is a time chart with the rising edge of the transmission signal output at the start of transmission of the wireless communication device 1 as a reference "t0". Changes in the detection signal, changes in the path switching signal by the switching control circuit 23, changes in the state of the switching circuit 22, changes in the amplification degree control signal output from the amplification control circuit 25, and changes in the transmission signal output from the amplifier 2 showing.

The wireless communication device 1 starts transmission. A transmission signal output from the wireless communication device 1 is input to the amplifying device 2 by starting transmission of the wireless communication device 1 . A transmission signal is transmitted to the antenna 3 by the switching circuit 22 via the amplitude limiting circuit 24 . A part of the transmission signal is also input to the switching control circuit 23 . As shown in FIG. 5, the amplitude level of the carrier of the transmission signal of the wireless communication device 1 gradually increases from "t0" when transmission is started.

The switching control circuit 23 detects and rectifies the carrier of the transmission signal, and converts it into a detection signal that is a DC voltage corresponding to the amplitude level of the carrier. In the detection signal shown in "switching control circuit/detection signal" in FIG. 5, the amplitude level of the carrier increases with the lapse of time, so the voltage value rises. Further, the switching control circuit 23 compares the voltage value of the detection signal with a predetermined voltage value, and outputs the path switching signal when the voltage value of the detection signal is equal to or higher than the predetermined voltage value. It is desirable that the time required for the amplifier 2 to enter the transmission state is short, and it is desirable that the transmission output of the wireless communication device 1 required to bring the amplifier 2 into the transmission state is low. It is desirable to set it low enough not to be affected by noise. Also, the predetermined voltage value is set lower than the detection signal generated by the amplitude level of the carrier whose amplitude level is limited by the amplitude limiting circuit 24, which will be described later.

The timing at which the switching control circuit 23 outputs the path switching signal is assumed to be "t1". As described above, the amplifying device 2 starts shifting to the transmission state at the timing of "t1". The path switching signal is transmitted to the switching circuit 22 and the amplification control circuit 25 .

The switching circuit 221 switches the transmission signal transmitted to the connector C1 from the amplitude limiting circuit 24 to the amplifying circuit 20 according to the path switching signal. Also, the switching circuit 222 switches the signal transmitted to the connector C2 from the signal transmitted from the amplitude limiting circuit 24 to the signal transmitted from the amplifier circuit. However, since the switching circuit 22 is not instantaneously switched by the path switching signal, the connection state (receiving state) between the connector C1 side and the amplitude limiting circuit 24 side indicated as "receiving" in the "switching circuit" of FIG. A period T1, a period T2 in which the connector C1 side described as "released" is released and not connected to any of the paths on the side of the amplitude limiting circuit 24 and the side of the amplifier circuit 20, these two periods T1 and T2. After a lapse of time, the switching circuit 221 switches to a connection state (transmission state) with the amplifier device 20 side. Similarly, the switching circuit 222 switches from the connector C2 side to the amplifier circuit 20 side after the periods T1 and T2.

As shown in FIG. 5, the timing at which the amplitude level of the carrier of the "wireless communication device/transmission signal" starts to be limited by the amplitude limiting element of the amplitude limiting circuit 24 is "t2". Also, the end timing of the period T1 (the start timing of the period T2) is assumed to be "t3". Furthermore, the end timing of the period T2 is assumed to be "t4". As described above, the transmission signal output from the wireless communication device 1 is supplied to the antenna 3 via the amplitude limiting circuit 24 since the switching circuit 22 is in the receiving state from "t0" to "t3". "Amplifying device/transmission signal" in FIG. 5 indicates changes in the amplitude level of the power supplied to the antenna 3 and changes in the amplitude level of the power output from the connector C2. The "amplifier/transmission signal" shown in FIG. less than the amplitude level of the transmission output. A dashed line in FIG. 5 indicates the case where the amplitude limiting function of the amplitude limiting circuit 24 does not limit the amplitude. Therefore, the amplitude level can be reduced until just before the switching circuit 22 is released at the timing of "t3".

The path switching signal is also transmitted to the amplification control circuit 25 . The amplification control circuit 25 outputs an amplification degree control signal for setting the amplification degree (gain) of the amplification circuit 20 to the amplification circuit 20 . As shown in FIG. 5, the amplification control circuit 25 increases the gain of the amplifier circuit 20 over a predetermined period of time from the transition of the timing "t1" of the path switching signal. The initial value of the gain set in the amplifier circuit 20 by the amplification control circuit 25 and the characteristics such as the slope and curve of the gain versus time are matters of design. However, at the timing of "t4" when the switching circuit 22 is in the transmission state, the gain set by the amplification control circuit 25 to the amplifier circuit 2 is in the process of increasing the gain, and after the predetermined time "t4" has passed, Gain should be maximized. It is desirable that the gain set in the amplifier circuit 2 by the amplification control circuit 25 starts increasing from the minimum gain state within the period T2.

On the other hand, as shown in FIG. 5, the switching circuit 22 is released at "t3" for the "radio communication device/transmission output", so that the amplitude limitation circuit 24 no longer limits the amplitude, and the radio communication device 1 returns to the original amplitude level at the start of transmission, and increases toward the transmission output set in the wireless communication device 1.

The amplitude level of the "amplifier/transmission signal" immediately after "t4" is obtained by amplifying the amplitude level of the transmission output of the wireless communication device 1 at "t4" by the amplifier circuit 20 based on the gain setting set by the amplification control circuit 25. amplitude level. The amplification control circuit 25 sets an appropriate gain for the amplifier circuit 20 so that the amplitude level of the transmission signal immediately after "t4" is equal to or lower than the amplitude level of the transmission signal immediately before "t3".

As described above, unnecessary radiation can be suppressed by lowering the amplitude level of the transmission output before and after the momentary interruption, that is, the amplitude level of the transmission output immediately before "t3" and the amplitude level of the transmission output immediately after "t4". . In the amplifying device 2 according to the first embodiment of the present invention, the amplitude level of the transmission output immediately before "t3" is limited by the amplitude limiting function (amplitude limiting circuit 24) of the amplitude limiting circuit 24, and the amplitude of the transmission output immediately after "t4" is By limiting the level by the amplification degree control signal of the amplification control circuit 25, it is possible to reduce the transmission output before and after the momentary interruption due to switching between transmission and reception of the carrier control system, and suppress unnecessary radiation.

(Embodiment 2)
In general, it is desirable for wireless communication to transmit with the minimum transmission power required for the communication. Therefore, it may not be necessary to increase the transmission output of the amplifying device 2 without changing the configuration of the wireless communication equipment 100 . Specifically, when the amplification device 2 does not need to increase the transmission output of the amplification device 2, it is necessary to stop the switching operation by carrier control and bypass the transmission signal from the wireless communication device 1 to supply it to the antenna 3. be. However, in Embodiment 1 of the present invention, since the detour path has an amplitude limiting function, even if the switching operation by carrier control is stopped while the amplifier device 2 is connected, the transmission signal of the wireless communication device 1 is transmitted from the antenna 3. cannot output.

FIG. 6 shows the configuration of an amplifier 2A according to Embodiment 2 of the present invention. An amplifier device 2A according to the second embodiment includes a second switching circuit 32 (321, 322), a bypass circuit 31, a filter circuit 30 and a second switching control circuit 33 in addition to the configuration of the first embodiment. The switching circuit in the first embodiment is the first switching circuit 22 (221, 222) in the second embodiment, and the switching control circuit 23 in the first embodiment is the first switching circuit 23 in the second embodiment. do.

The second switching control circuit 33 selects the path (detour path) connecting the wireless communication device 1 and the antenna 3 via the detour circuit 31 for the second switching circuit 32, or selects the amplifier circuit 20 or the amplitude limiting circuit 24. to select a path (amplification path) connecting the wireless communication device 1 and the antenna 3 via any one of . Further, the second switching control circuit 33 may stop supplying power to the amplifier circuit 20, the first switching circuit 22, the first switching control circuit 23, and the amplification control circuit 25 when selecting the detour path. . The second switching control circuit 33 outputs a detour selection signal when selecting a detour path, and outputs an amplification selection signal when selecting an amplification path.

In the second switching circuit 32, the second switching circuit 321 is arranged on the input side (connector C1 side), and the second switching circuit 322 is arranged on the output side (connector C2 side). The second switching circuit 32 switches the route connecting the wireless communication device 1 and the antenna 3 according to the detour selection signal or amplification selection signal output from the second switching control circuit 33 .

The detour circuit 31 is a circuit that connects the wireless communication device 1 and the antenna 3 when the second switching control circuit 33 outputs a detour selection signal and the second switching circuit 32 selects the detour route. Although the detour circuit 31 does not require any particular circuit components, it must be a path with little transmission loss because a high-frequency transmission signal or reception signal passes through it. The bypass circuit 31 may use a component such as a coaxial cable as needed.

The filter circuit 30 suppresses harmonics generated by the amplifier circuit 20 . The filter circuit 30 is, for example, a low-pass filter whose cutoff frequency is set so as to suppress harmonics in a frequency band that can be amplified by the amplifier circuit 20 . The filter circuit 30 is arranged on the output side of the amplifier circuit 20 in the amplification path. Specifically, the filter circuit 30 is arranged between the switching circuit 222 and the switching circuit 322 . That is, the filter circuit 30 does not intervene in the path of the second bypass circuit. Therefore, the detour path is capable of transmitting signals outside the frequency band that can be amplified by the amplifier circuit 20 . For example, when the transmission frequency of the wireless communication device 1 has a frequency band other than the frequency band that can be amplified by the amplifier circuit 20, and the transmission frequency of the wireless communication device 1 is other than the frequency band that can be amplified by the amplifier circuit 20 When performing communication in the frequency band of , the amplifier device 20A can perform communication via the second detour. If the wireless communication device 1 cannot communicate in a frequency band outside the frequency band that can be amplified by the amplifier circuit 20, the filter circuit 30 may be arranged between the second switching circuit 322 and the connector C2.

The filter circuit 30 also suppresses harmonics generated by the amplitude limiting circuit 24 limiting the amplitude. The amplitude limiting circuit 24 distorts the passing signal in order to limit the original amplitude so that it does not exceed a certain amplitude level. Since this distortion occurs over a wide band, it also contains harmonic components. The periods of “t2” and “t3” shown in FIG. 4 of the first embodiment are periods during which the amplitude level of the transmission signal from the wireless communication device 1 is suppressed by the amplitude limiting circuit 24 . During this period, although the amplitude level is limited, a broadband signal that should not be output is generated. Therefore, the filter circuit 30 is arranged between the switching circuit 222 and the switching circuit 322 so as not to supply part of the wideband signal generated by the amplitude limiting circuit 24 to the antenna.

The amplifier 2A according to the second embodiment of the present invention does not show the configuration of the operation unit operated by the worker who uses the wireless communication equipment 100, but the power switch and the bypass circuit are used or amplified. An operation unit may be provided for receiving an operation for selecting whether to use the circuit. When the power switch of the amplifying device 2A is off, that is, in the initial state, the bypass circuit is selected. In the amplifier 2A according to the second embodiment, when the power switch is on and the detour circuit is selected, no input signal is transmitted to the first switching control circuit, so switching between transmission and reception by the carrier control method does not occur. However, since there is no point in supplying power to circuits such as the amplifier circuit 20, the amplification control circuit 25, and the first switching control circuit 23, the second control circuit does not supply power to these circuits when the detour circuit is selected. supply may be stopped.

The amplifying device 2A according to the second embodiment of the present invention has the configuration described above.
(1) When an amplification path is selected, as in the first embodiment, it is possible to reduce the transmission output before and after the momentary interruption caused by switching between transmission and reception in the carrier control system, thereby suppressing unnecessary radiation. again,
(2) When the detour route is selected, power supply to the amplifier circuit 20, the first switching circuit 22, the switching control circuit 23, and the amplification control circuit 25 is stopped, thereby reducing the power consumption of the amplifier device 2. can do. Furthermore,
(3) When the wireless communication device 1 can transmit and receive a frequency band other than the frequency band that can be transmitted by the amplifier device 2, the signal in the frequency band other than the frequency band that can be transmitted by the amplifier device 2 is The wireless communication device 1 and the antenna 3 can be connected without passing through the filter circuit 30 .

(Embodiment 3)
FIG. 7 shows the configuration of an amplifier 2B according to Embodiment 3 of the present invention. The amplifying device 2B according to the third embodiment of the present invention is characterized in that by stopping the amplitude limiting function of the amplitude limiting circuit 24 in the first embodiment, a bypass path is substantially provided. The detour route connects the wireless communication device 1 and the antenna 3 without the amplification circuit 20 when the transmission output of the wireless communication device 1 is not increased by the amplification device 20 .

The amplifier device 2 according to the third embodiment of the present invention includes a filter circuit 40 and a control circuit 43 in addition to the configuration of the first embodiment. The amplitude limiting circuit 44 in the third embodiment is different from the amplitude limiting circuit 24 in the first embodiment. The control circuit 43 controls to stop or operate the amplitude limiting function of the amplitude limiting circuit 44 . The filter circuit 40 is a low-pass filter that mainly suppresses the frequency band of harmonics of the amplifier circuit 20, as in the second embodiment.

Details of the amplitude limiting circuit 41 of the amplifying device 2 according to the third embodiment of the present invention will be described with reference to FIG. The amplitude limiting circuit 44 shown in FIG. 8 includes a transmission circuit 441 , a switch 442 and an amplitude limiting element 443 . The transmission circuit 441 is a path that is connected to the switching circuit 221 and the switching circuit 222 and transmits a transmission signal (input signal) output from the wireless communication device 1 to the antenna 3 . The switch 442 is a switch that connects or disconnects the amplitude limiting element 443 to or from the transmission circuit 441 according to a control signal output from the control circuit 43 . In other words, the switch 442 is an amplitude limit release circuit that releases the amplitude limit of the amplitude limit circuit 44 . Amplitude limiting element 443 limits the amplitude of the signal transmitted to transmission circuit 441 to a predetermined amplitude level while being connected to transmission circuit 441 via switch 442 . Also, since the connection to the transmission circuit 441 is released when the switch 442 is released, the amplitude limiting element 443 does not limit the amplitude of the signal transmitted to the transmission circuit 441 .

The control circuit 43 of the amplifier device 2 according to the third embodiment of the present invention outputs a signal for controlling the switch 442 in the amplitude limiting circuit 44 . When the wireless communication device 1 performs communication via the amplification device 2 and performs communication by performing amplification by the amplification device 2, the control circuit 43 performs control to turn on the switch 442 to turn on the amplitude limiting circuit 44. Activate the amplitude limiting function. As described above, the amplifying device 2 according to the third embodiment of the present invention suppresses unnecessary radiation that occurs when the transmission signal is interrupted at the time of switching between transmission and reception by the carrier control method by the amplitude limiting function.

When the wireless communication device 1 performs communication via the amplifier 2 and performs communication without amplification by the amplifier 2, the control circuit 43 performs control to turn off the switch 442, thereby controlling the amplitude limiting circuit. 44 stops the operation of the amplitude limiting function. By turning off the amplitude limiting function of the amplitude limiting circuit 44 by the control circuit 43 , the amplitude limiting circuit 44 substantially becomes a detour path within the amplifying device 2 .

FIG. 9 shows a modification of the amplitude limiting circuit 44 of the amplifying device 2 according to Embodiment 3 of the present invention. The switch 442 of the third embodiment only opens and closes, but in the modified example, a bidirectional contact is used to switch between the transmission path 441 and the path of the amplitude limiting element 443 . In the amplitude limiting circuit 44 of the third embodiment, since the switch 442 and the amplitude limiting element 443 are connected to the transmission path 441, the pattern of connection to the switch 442 may vary depending on the frequency of the signal transmitted through the transmission path 441. The length and electrical length inside the switch 442 may have an effect. On the other hand, in the configuration of the modification, since it is not affected by the length of the connection pattern to the switch 442, when the frequency at which communication is performed by the wireless communication equipment 100 is relatively high, for example, 1 GHz or higher, the modification is preferable.

In the amplifier device 2A according to the second embodiment of the present invention, when the power switch is in the ON state and the detour circuit is selected, the input signal is not transmitted to the first switching control circuit. do not have. However, in the third embodiment, even if the amplitude limiting function of the amplitude limiting circuit 44 is released and the circuit is substantially a detour circuit, the input signal is input to the switching control circuit 23, so switching between transmission and reception by the carrier control method does not occur. end up Therefore, the control circuit of the amplifier circuit 2B of the third embodiment cancels the amplitude limiting function of the amplitude limiting circuit 44 and performs control to stop at least the carrier detection operation of the switching control circuit 23 . Since there is no point in supplying power to circuits such as the amplifier circuit 20 and the amplification control circuit 25, the control circuit stops supplying power to these circuits when the amplitude limiting function of the amplitude limiting circuit 44 is cancelled. You can stop.

The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the gist of the present invention.

1 wireless communication device 2 amplifier device 3 antenna 100 wireless communication equipment 20 amplifier circuit 21 detour circuit 22 switching circuit (first switching circuit)
23 switching control circuit (first switching control circuit)
24 amplitude limiting circuit 241 transmission path 243 amplitude limiting element 25 amplification control circuit 30 filter circuit 32 second switching circuit 33 second switching control circuit 43 control circuit 44 amplitude limiting circuit 441 transmission circuit 442 switch 443 amplitude limiting element

Claims (5)

an amplifier circuit that amplifies an input signal;
an amplitude limiting circuit that limits the amplitude of the input signal;
a switching circuit that switches connection between a path via the amplifier circuit and a path via the amplitude limiting circuit;
a switching control circuit that detects the input signal and controls the switching circuit to switch connection from a path via the amplitude limiting circuit to a path via the amplifier circuit when the input signal is detected;
Amplification device with. An amplification control circuit for controlling the amplification degree of the amplification circuit,
In a non-connection period during which the switching circuit switches the connection between the path of the amplitude limiting circuit and the path of the amplifying circuit,
The amplification control circuit controls the amplification circuit to
setting to start amplification of the amplifier circuit from a first predetermined time within the non-connection period;
Furthermore, performing control to increase the amplification degree of the amplifier circuit over time,
The amplification device according to claim 1. a detour circuit that outputs the input signal without passing through the amplifier circuit or the amplitude limiter circuit;
a second switching circuit that switches connection between a path via the detour circuit and a path via the amplifier circuit or the amplitude limiting circuit;
a filter that suppresses frequencies corresponding to harmonics of an input signal in a path between a switching circuit on the output side of the amplifier circuit or the amplitude limiting circuit and a second switching circuit on the output side of the detour circuit;
a second switching control circuit that performs control to connect the second switching circuit to either a path via the detour circuit or a path via the amplifier circuit or the amplitude limiting circuit;
3. The amplifier circuit according to claim 2, wherein the second switching control circuit controls connection to the path via the detour circuit, and controls the switching control circuit to stop the operation of detecting the input signal. . The amplitude limiting circuit includes an amplitude limit canceling circuit that cancels amplitude limit,
a control circuit that outputs an amplitude limit release signal for releasing the amplitude limit to the amplitude limit release circuit and controls the switching control circuit to stop the operation of detecting the input signal;
3. The amplifier device according to claim 2. The amplitude limiting circuit is
a transmission circuit for transmitting a signal within the amplitude limiting circuit;
an amplitude limiting element that limits the amplitude of a signal transmitted to the transmission circuit;
with
The amplitude limit releasing circuit releases the amplitude limit by releasing the connection between the transmission circuit and the amplitude limiting element.
5. The amplifier device according to claim 4.

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