JP2002076802A - Transmitter-receiver for microwave band and semiconductor amplifier used for it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmitter-receiver that suppresses a loop gain even for one cell of a semiconductor element of a multi-cell synthesis form being a component of a semiconductor amplifier so as to suppress oscillation of a frequency with a multiple of 1/2. SOLUTION: The transmitter-receiver is provided with an antenna 1 that sends/ receives a microwave, a transmission reception changeover switch 2 that is connected to the antenna to switch the transmission reception, a mixer 5 that is connected to the transmission reception changeover switch with a filter 4, a mixer 5 that mix the received signal with a local oscillation signal to convert the frequency of the received signal into an intermediate frequency signal, a signal processing circuit 8 that processes the intermediate frequency signal, a modulator 9 that modulates the signal, a phase shifter 11 that shifts the phase of the modulated signal, and a semiconductor amplifier 12 that gives the signal whose phase is shifted to the antenna via the transmission reception changeover switch. The semiconductor amplifier 12 is configured to have the multi-cell synthesis form, a matching circuit 141A that is connected to this semiconductor element, and a stub 14b that is provided on the matching circuit to suppress oscillation of a frequency with a multiple of 1/2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitting / receiving device for a microwave band and a semiconductor amplifier for use in the transmitting / receiving device, and more particularly to a semiconductor amplifier for use therein.
The present invention relates to a transmission / reception device capable of suppressing harmonic oscillation and a semiconductor amplifier used therein.

[0002]

2. Description of the Related Art FIG. 5 shows a basic block diagram of a conventional transmitting / receiving apparatus used in a microwave band. In this figure, 1 is an antenna, 2 is a transmission / reception switch connected to the antenna, 3 is a preamplifier to which a received signal is input, 4 is a filter for removing a signal in a predetermined frequency range from an output of the preamplifier, Reference numeral 5 denotes a mixer that mixes the output of the filter 4 and a signal from the local oscillator 6 to generate an intermediate frequency signal, 7 denotes an amplifier for the intermediate frequency signal, and 8 denotes a signal processing circuit. 9 is a modulator for modulating a signal to be transmitted, 10 is a driver amplifier, 11 is a phase shifter provided when an array antenna or the like is used, 12 is a semiconductor amplifier for amplifying a transmission signal and inputting it to the antenna 1. It is well known as a high power internally matched transistor.

FIG. 6 is a block diagram showing an example of a schematic configuration of the semiconductor amplifier 12. As shown in FIG. In this drawing, reference numeral 13 denotes a semiconductor element having a number of cells corresponding to the number of gate pads, and these cells are combined to form one semiconductor element. 131 is a gate pad and 132 is a drain pad, each of which is provided with 12 pads, and each pad is further divided into 4 groups each having 3 as a group. 1
Reference numeral 4 denotes a first circuit board for forming a circuit connected to the gate pad 131, which is made of, for example, barium titanate and has four T-shaped matching circuits 141 to 1 on its surface.
44 are formed. One of the matching circuits 141 is connected as shown to three gate pads constituting the first group of the gate pads 131 by wires 133 of copper or the like, and the other matching circuits 142 to 144 are similarly connected. They are respectively connected to three gate pads constituting the second to fourth groups.

Reference numeral 15 denotes a second circuit board which constitutes an input side matching circuit together with each matching circuit of the first circuit board 14, and is formed of, for example, alumina, and has two C-shaped matching circuits 151, 152 on its surface. And a matching circuit 153 connecting the respective matching circuits 151 and 152 are formed. 154 is C
-Shaped matching circuit 151 and T-shaped matching circuits 141 and 142
And 155 are also C-shaped matching circuits 1
Wires 156 connecting the T. 52 and the T-type matching circuits 143 and 144 are input terminals. Reference numeral 16 denotes a third circuit board for forming a circuit connected to the drain pad 132, which is made of, for example, barium titanate.
On its surface, four T-shaped matching circuits 161 to 164 are formed. One of the matching circuits 161 is a wire 1 made of copper or the like.
At 34, three drain pads 132 forming a first group of the drain pads 132 are connected as shown,
Similarly, the other matching circuits 162 to 164 are respectively connected to the three drain pads constituting the second to fourth groups.

Reference numeral 17 denotes a fourth circuit board which constitutes an output-side matching circuit together with each matching circuit of the third circuit board 16, and is formed of, for example, alumina and has two C-shaped matching circuits 171 and 172 on its surface. And a matching circuit 173 connecting the matching circuits 171 and 172 are formed. 174 is C
-Shaped matching circuit 171 and T-shaped matching circuits 161 and 162
175 is a C-shaped matching circuit 1
Wires 176 connecting the 72 and the T-type matching circuits 163 and 164 are output terminals. FIG. 7 shows an equivalent circuit of the semiconductor amplifier 12 shown in FIG.

Next, the operation of the semiconductor amplifier, in particular, the occurrence of 1 / 2f0 oscillation with respect to the frequency f0 of the input signal will be described. The cell constituting the semiconductor element 13 is composed of FETs as shown in the equivalent circuit of FIG. 7, but for simplicity of description, attention is paid to two FETs connected by a T-type matching circuit. When the input signal power to the semiconductor amplifier increases, the FET operates in a non-linear manner, as is well known. Assuming that the frequency of the input signal is f0, a signal component having a frequency f0 / 2 of a noise component existing in a closed loop including two FETs and a T-type matching circuit connected thereto is F0.
The signal is fed back by the reflection characteristics of the ET, mixed with the input signal f0, and a signal component of f0 / 2 is generated again in the closed loop.

When the input signal power is small, the mixing effect with f0 / 2 is small, but when the input signal power is large, the mixing effect with f0 / 2 is large. In that case,
The S parameter which is a four-terminal parameter for f0 / 2 is f0
May vary depending on the amplitude and phase (relative phase with respect to f0 / 2) of the input signal, and may satisfy the loop oscillation condition with respect to f0 / 2. Since the phase of the noise signal of f0 / 2 occurs randomly and the initial phase can take an arbitrary value, if any of the initial phases satisfies the condition of loop oscillation, loop oscillation occurs there. When the f0 / 2 oscillation occurs, the power of f0 is consumed by f0 / 2, and as a result, the output characteristics deteriorate as shown by A in FIG.

[0008]

As described above, in a conventional transmitting / receiving device used in the microwave band, particularly in a semiconductor amplifier thereof, output degradation occurs due to gate mixer operation and loop gain (loop oscillation). Therefore, as shown by R in FIGS. 6 and 7, an isolation resistor is inserted on the circuit loop to suppress the f0 / 2 oscillation. That is, in the semiconductor amplifier shown in FIG.
Since a combined matching circuit is configured, there are three types of closed loops L1, L2, and L3 as shown by a dashed line in FIG. Loop L1 includes matching circuits 153 and 173,
The loop L2 includes the C-type matching circuits 151, 152 and 171, 172.
And T-type matching circuits 141, 142, 161, and 162, and C-type matching circuits 152, 172 and T-type matching circuits 143, 144, 163, and 164.
The loop L3 includes T-type matching circuits 141 to 144 and 161-1.
64 and one adjacent two cells. Since there are two loops L3 between one of the T-type matching circuits 141 to 144 and one of the corresponding T-type matching circuits 161 to 164, there are a total of eight loops. Only one loop is shown.

As shown in FIGS. 6 and 7, when an isolation resistor R is inserted into these loops, an effective isolation resistor is inserted into the matching circuits for the loops L1 and L2. Therefore, it is possible to stabilize the loop and to suppress the loop gain. However, since there is no place to mount an isolation resistor for the loop L3, a loop using the isolation resistor is provided for this loop. There is a problem that the gain cannot be suppressed. That is, it is possible to take measures against oscillation by suppressing the loop gain for a loop extending over two or more cells of the semiconductor element, but it is not possible to take measures against oscillation for one cell. .

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems in the conventional device, and a microwave transmission / reception device capable of taking effective oscillation countermeasures even for one cell, and a transmission / reception device therefor. It is an object to provide a semiconductor amplifier to be used.

[0011]

A microwave transmission / reception apparatus according to the present invention includes an antenna for transmitting / receiving a microwave, a transmission / reception switch connected to the antenna for switching between transmission and reception, and a transmission / reception switch. A mixer that is connected via a filter and mixes a received signal with a local oscillation signal and converts the signal into an intermediate frequency signal, a signal processing circuit that processes the intermediate frequency signal, and a modulator that modulates the signal;
In a transmission / reception device having a phase shifter that shifts a phase of a modulated signal and a semiconductor amplifier that inputs the phase-shifted signal to an antenna via a transmission / reception switch, the semiconductor amplifier includes:
The semiconductor device includes a multi-cell composite type semiconductor element, a matching circuit connected to the semiconductor element, and a stub provided on the matching circuit for suppressing 1/2 harmonic oscillation.

A semiconductor amplifier used in a microwave band transmitting / receiving apparatus according to the present invention is a multi-cell combined semiconductor device, a matching circuit connected to the semiconductor device, and a semiconductor device provided on the matching circuit. And a λ / 2 open stub of a fundamental wave connected to the cell.

A semiconductor amplifier used in a microwave band transmitting / receiving apparatus according to the present invention further includes a multi-cell combined type semiconductor element and a matching circuit board having a multilayer structure. / 2 open stub.

The semiconductor amplifier used in the transmitting / receiving device for microwave band according to the present invention is characterized in that it is a high-output internal matching transistor.

A semiconductor amplifier used in a microwave band transmitting / receiving apparatus according to the present invention further includes a first matching circuit board.
The layer is a matching circuit, one surface of the second layer is a λ / 2 open stub of a fundamental wave, the other surface of the second layer is ground for the first layer,
The layer is a ground for the second layer.

The semiconductor amplifier used in the microwave transmitting / receiving apparatus according to the present invention further includes a first matching circuit board.
The layer is a λ / 2 open stub of the fundamental wave, the second layer is a matching circuit for the first layer, and the third layer is a ground for the second layer.

In the semiconductor amplifier used in the microwave transmitting / receiving device according to the present invention, the respective layers constituting the matching circuit board are electrically connected to each other by through holes.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. Embodiment 1
Is characterized by a semiconductor amplifier among the microwave band transmission / reception devices, and devices other than the semiconductor amplifier are the same as the conventional transmission / reception device shown in FIG.
The description of the entire transmitting / receiving apparatus is omitted. FIG. 1 is a circuit diagram showing a semiconductor amplifier 12 according to a first embodiment of the present invention.
FIG. 2 is a schematic diagram showing a partial configuration of the embodiment. In this figure, 1
Reference numeral 3 denotes a semiconductor element which is formed by combining a large number of cells and has the same number of gate pads 131 as in FIG. 6, but only three are shown in the figure.
14A is a circuit board for forming a circuit connected to the gate pad 131; 141A is a matching circuit formed on the circuit board 14A;
Is set to a size that can correspond to.

141B, 141C, 141D are stubs formed by metallizing on the matching circuit 141A, and are λ / 2 open stubs (1/2) with respect to the fundamental wave.
Short stub for harmonics). 133
B, 133C and 133D are stubs 141B and 141, respectively.
C, a copper wire connecting 141D and the gate pad 131. Although a plurality of circuit boards 14A are provided corresponding to the number of gate pads 131, only one is shown in this figure. FIG. 2 is an equivalent circuit of the semiconductor amplifier 12 including the configuration of FIG. In this figure, the same or corresponding parts as those in FIG. In the first embodiment, as described above,
A stub provided on the matching circuit and connected to each cell of the semiconductor device is connected to a λ / 2 open stub (1
(Short stub for the 1/2 harmonic), the stub is open in the used band, and the circuit is short-circuited for the 1/2 harmonic. Therefore, the gain of the 1/2 harmonic can be reduced for one cell, and
As a result, it is possible to effectively prevent the output characteristics from deteriorating.

Embodiment 2 Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a schematic diagram showing a partial configuration of a semiconductor amplifier, and FIG. 4 is a schematic diagram showing a connection relationship between a multilayered matching circuit board and a semiconductor element and a configuration of each layer of the matching circuit board. In these figures, 2
Reference numeral 0 denotes a substrate constituting a package, and 13 denotes a semiconductor element mounted on the substrate 20, which is formed by synthesizing a large number of cells as in FIG. 6, and provided with the same number of gate pads 131 as the cells. However, FIG. 4 shows only three. Reference numeral 21 denotes a matching circuit board corresponding to the first circuit board 14 in FIG. 6, which has a three-layer structure as described below. That is, 211 is a matching circuit layer constituting the first layer,
As shown in FIG. 3, while being mounted on the substrate 20,
As shown in FIG. 4, a matching circuit 211A is formed.

Numeral 212 denotes a λ / 2 open stub layer constituting a second layer, which is mounted on the upper surface of the matching circuit layer 211 as shown in FIG. 3 and has a basic surface as shown in FIG. The number of the λ / 2 open stubs 212A for the waves is equal to the number of the gate pads 131. Note that λ / 2
On the other surface of the open stub layer 212, a ground (not shown) for the first-layer matching circuit 211A is formed. Reference numeral 213 denotes a ground layer constituting a third layer.
A ground 213A for the λ / 2 open stub 212A of the layer is formed. Reference numeral 214 denotes through-holes extending from the third-layer ground layer 213 to the first-layer matching circuit 211A. The through-holes are formed in the same number as the gate pads 131. It is connected. In addition, since each layer is formed of a ceramic substrate, the adhesion between the layers is performed by baking under pressure or the like. With such a configuration, the gain of the 1/2 harmonic can be reduced for one cell, as in the first embodiment.
It is possible to suppress harmonic oscillation and prevent deterioration of output characteristics.

[0022]

According to the transmission / reception apparatus for microwave band according to the present invention, the semiconductor amplifier comprises: a multi-cell composite type semiconductor element;
Since the matching circuit is provided with the matching circuit connected to the semiconductor element and the stub provided on the matching circuit and suppressing the half-wave oscillation, it is possible to effectively prevent the output characteristics from deteriorating.

A semiconductor amplifier used in a microwave band transceiver according to the present invention is a multi-cell combined semiconductor device, a matching circuit connected to the semiconductor device, and a semiconductor device provided on the matching circuit. Λ / 2 open stub of the fundamental wave connected to each of the cells, the gain of the 倍 harmonic can be reduced even for one cell, and the oscillation of the 倍 harmonic can be suppressed. As a result, deterioration of the output characteristics can be prevented.

Further, the semiconductor amplifier used in the transmitting / receiving device for microwave band according to the present invention further comprises a multi-cell composite type semiconductor element and a matching circuit board having a multilayer structure, and the matching circuit board has a fundamental wave. Λ / 2 open stub layer, which suppresses 1/2 harmonic oscillation to prevent deterioration of output characteristics and facilitates arrangement and connection of λ / 2 open stub. It is.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a partial configuration of a semiconductor amplifier according to a first embodiment of the present invention;

FIG. 2 is an equivalent circuit diagram of the semiconductor amplifier shown in FIG.

FIG. 3 is a schematic diagram illustrating a partial configuration of a semiconductor amplifier according to a second embodiment of the present invention;

FIG. 4 is a schematic diagram showing a configuration of each layer of a multilayered matching circuit board.

FIG. 5 is a block diagram showing a basic configuration of a conventional microwave band transmitting / receiving device.

FIG. 6 is a block diagram illustrating a schematic configuration of a semiconductor amplifier in a conventional transmitting / receiving device.

FIG. 7 is an equivalent circuit diagram of the semiconductor amplifier shown in FIG. 6;

FIG. 8 is an output characteristic diagram of a conventional semiconductor amplifier.

[Explanation of symbols]

Reference Signs List 1 antenna, 2 transmission / reception switch, 4 filter, 5 mixer, 8 signal processing circuit, 9 modulator, 11
Phase shifter, 12 semiconductor amplifier, 13 semiconductor device, 1
4, 15 input side matching circuit, 16, 17 output side matching circuit, 21 matching circuit board, 131 gate pad, 13
3 wire, 141A matching circuit, 141B, 141
C, 141D λ / 2 open stub, 211 matching circuit layer, 212λ / 2 open stub layer, 213 ground layer, 214 through hole.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5J067 AA04 AA21 AA41 CA54 FA20 HA38 KA16 KA29 KA32 KA41 KA53 KA66 KA68 KS11 QA03 QA04 SA13 TA01 TA02 5J069 AA04 AA21 AA41 CA54 FA20 HA38 KA16 KA29 KA31 KA29 TA02 5J091 AA04 AA21 AA41 CA54 FA20 HA38 KA16 KA29 KA32 KA41 KA53 KA66 KA68 QA03 QA04 SA13 TA01 TA02 5K011 DA22 DA25 KA13

Claims (7)

[Claims] An antenna for transmitting and receiving microwaves, a transmission / reception switch connected to the antenna for switching between transmission and reception, and connected to the transmission / reception switch via a filter to mix a received signal with a local oscillation signal. A mixer that converts the signal into an intermediate frequency signal; a signal processing circuit that processes the intermediate frequency signal; a modulator that modulates the signal; a phase shifter that shifts the phase of the modulated signal; In a transmission / reception device having a semiconductor amplifier inputting to an antenna via a transmission / reception changeover switch, the semiconductor amplifier is provided on a semiconductor element of a multi-cell composite type, a matching circuit connected to the semiconductor element, and the matching circuit. , 1
And a stub that suppresses half-wave oscillation. 2. A semiconductor amplifier, comprising: a multi-cell composite semiconductor element; a matching circuit connected to the semiconductor element; and a fundamental wave provided on the matching circuit and connected to each cell of the semiconductor element. 2. The semiconductor amplifier according to claim 1, further comprising a λ / 2 open stub. 3. A semiconductor amplifier comprising a multi-cell composite type semiconductor element and a matching circuit board having a multilayer structure, wherein the matching circuit board includes a λ / 2 open stub layer of a fundamental wave. A semiconductor amplifier used for the microwave band transmitting / receiving device according to claim 1. 4. The semiconductor amplifier according to claim 1, wherein the semiconductor amplifier is a high-output internal matching transistor. 5. A matching circuit board, wherein the first layer is a matching circuit, one surface of the second layer is a λ / 2 open stub of a fundamental wave, the other surface of the second layer is a ground for the first layer, and the third layer is a ground of the first layer. 4. The semiconductor amplifier used for a microwave band transmitting / receiving device according to claim 3, wherein a ground is provided for the two layers. 6. The matching circuit board according to claim 1, wherein the first layer has a wavelength of λ /
2 open stubs, the second layer is a matching circuit for the first layer,
4. The semiconductor amplifier according to claim 3, wherein the third layer is a ground for the second layer. 7. The semiconductor amplifier used in a microwave band transmitting / receiving device according to claim 5, wherein each layer constituting the matching circuit board is electrically connected to each other by a through hole.