JPH06276019A - Monolithic microwave oscillator - Google Patents

Abstract

PURPOSE:To provide a microwave signal source which is high in frequency stability, and is small in size, inexpensive, and reducible in power consumption. CONSTITUTION:This monolithic microwave oscillator is equipped with an FET 2 formed on a semi-insulating GaAs substrate 1, a matching circuit 4, feedback circuits 6 and 9, a transmission line 8 connected to the feedback circuit 9, a resistance 11, a dielectric resonator 15, bias lines 26 and 27, and terminals 3, 5, 10, 16, and 17. For frequency stabilization, a dielectric resonator 15 of specific size is coupled with the transmission line 8 of the feedback circuit formed on the GaAs substrate 1 where an oscillator circuit is formed. Consequently, the oscillation circuit is reduced in size, lowered in price, and shortened in development period.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stabilized monolithic microwave oscillator used in satellite communication and the like.

[0002]

2. Description of the Related Art In recent years, with the progress of technologies such as satellite broadcasting, microwave communication, and microwave measurement, broadband, low power consumption,
In addition, the demand for small-sized stabilized microwave oscillators is increasing. A dielectric resonator is used as one means for stabilizing the frequency of a microwave oscillator. Previously, C.Tsironics et al; IEEE Trans.on Micr
As disclosed in Owave Theory and Techniques, MTT-31,3,312 (1983)), an oscillator with a dielectric resonator having a chip structure shown in FIG. 2 has been reported. In the oscillator of FIG. 2, the FET 2 is formed on the semi-insulating GaAs substrate 1, the matching circuit 4 is formed between the drain terminal 21 of the FET 2 and the output terminal 3, and the source terminal 22 of the FET 2 is connected as shown in FIG. First, a monolithic oscillator was realized by connecting the first feedback circuit 6 between the ground terminals 5 and forming the second feedback circuit 9 between the gate terminal 23 of the FET 2 and the bonding pad 13. Next, the ceramic substrate 7 is separately prepared, the transmission line 8, the ground terminal 10 and the resistor 11 are formed on the ceramic substrate 7, and the bonding wire 1
2 is used to electrically connect the bonding pad 13 on the GaAs substrate 1 to one end of the transmission line 8 on the ceramic substrate 7, and to couple the dielectric resonator 15 to the transmission line 8 to connect the oscillator. It was trying to stabilize the frequency.

[0003]

[Problems to be Solved by the Invention] As described above,
In the past, in order to stabilize the frequency of a monolithic oscillator, it was necessary to separately design a monolithic oscillator chip and a ceramic substrate for dielectric resonator coupling, prototype them, and connect them by soldering and wire bonding work. . Therefore, there are drawbacks that the development period of the stabilized oscillator is long, the size is large, and the price is high. As described above, the conventional microwave oscillator has problems to be solved in terms of development period, size, and price.

An object of the present invention is to solve the above problems and to provide a stabilized monolithic microwave oscillator which is easy to reduce in size and cost and development period.

[0005]

According to the present invention, a FET is formed on a semi-insulating GaAs substrate, and a matching circuit is formed between the drain terminal and the output terminal of the FET.
First end of the source terminal is connected to the ground terminal
An oscillator in which the other end of the feedback circuit is connected to the gate terminal of the FET and the other end of the second feedback circuit is connected to the ground terminal through the resistor formed on the substrate, A dielectric resonator having predetermined electric characteristics is provided on the GaAs substrate, and the dielectric resonator is coupled to a transmission line provided between the second feedback circuit and the resistor. A characteristic monolithic microwave oscillator is obtained.

Further, according to the present invention, semi-insulating GaA
Heterojunction bipolar transistor, HEMT on s substrate
Alternatively, any one of the other transistors may be formed, a matching circuit may be formed between the collector terminal and the output terminal of the transistor, and the other end of the first feedback circuit whose one end is connected to the ground terminal may be An oscillator in which a second feedback circuit connected to an emitter terminal of a transistor and having one end connected to a ground terminal through a resistor formed on the substrate is connected to a base terminal of the transistor A dielectric resonator having the electrical characteristics of 1. is provided on the GaAs substrate, and the dielectric resonator is coupled to a transmission line provided between the second feedback circuit and the resistor. A monolithic microwave oscillator is obtained.

[0007]

According to the present invention, the transmission line for connecting the second feedback circuit and the resistor is formed on the GaAs substrate, and the dielectric resonator for stabilizing the oscillation frequency is provided on the GaAs substrate. It is connected to the track. Traditionally,
As shown in FIG. 2, the ceramic substrate 7 is provided separately from the GaAs substrate 1 and the dielectric resonator is provided on the ceramic substrate 7, whereas in the present invention, one Ga is provided as described above.
Since all the constituent elements are mounted on the As substrate and integrated into one chip, the design and trial manufacturing process can be performed only once. Further, in the production of the conventional microwave oscillator shown in FIG. 2, the work of soldering and wire bonding was required to electrically connect the ceramic substrate 7 and the GaAs substrate 1, but the microwave oscillator of the present invention has There is no need for that work in production.

[0008]

1 is a chip configuration diagram of an embodiment of a monolithic microwave oscillator according to the present invention. As shown in the figure, the FET 2 is formed on the semi-insulating GaAs substrate 1, and F
The matching circuit 4 is formed between the drain terminal 21 of the ET2 and the output terminal 3, and the source terminal 22 and the ground terminal 5 of the FET2 are formed.
The first feedback circuit 6 is connected between the two, the second feedback circuit 9 is connected to the gate terminal 23 of the FET2, and the length (2K + 1) / 4 wavelength (where K is provided between the second feedback circuit 9 and the ground terminal 10). =
A transmission line 8 having a characteristic impedance of 50Ω and a resistor 11 having a resistance of 50Ω are connected in series. On the other hand, for supplying the drain bias, the bias line 26 and the drain bias terminal 1 having a characteristic impedance of 200Ω
6, a bias line 27 having a characteristic impedance of 200Ω and a gate bias terminal 17 are used to supply the gate bias. Finally, a dielectric resonator 15 having a predetermined resonance frequency is coupled to a predetermined position of the transmission line 8 to obtain a frequency-stabilized monolithic microwave oscillator.
The lengths of the first feedback circuit 6 and the second feedback circuit 9 are set such that the drain terminal 21 to the FET 2 at a predetermined oscillation frequency.
The real part of the impedance when viewed is adjusted to be negative. Further, the matching circuit 4 is adjusted so that the oscillation signal at the load of 50Ω connected to the output terminal 3 becomes maximum at the oscillation frequency.

Although the FET is used as the amplifying element in the embodiment, the monolithic microwave oscillator of the present invention is
Heterojunction bipolar transistor (HBT), HEM
It can also be realized by using a transistor such as a T (High Electron Mobility Transistor) as an amplification element.

[0010]

In such a monolithic microwave oscillator of the present invention, in order to stabilize the frequency, the dielectric resonator is directly coupled to the transmission line on the GaAs substrate on which the oscillator circuit is formed. There is. Therefore, the necessity of the ceramic substrate, extra soldering and wire bonding work, or the design and trial production of the circuit formed on the ceramic substrate, which has been conventionally required, is eliminated. Therefore,
The present invention has the effects that the oscillator circuit can be downsized, the cost can be reduced, and the development period can be shortened.

[Brief description of drawings]

FIG. 1 is a chip configuration diagram of a stabilized monolithic microwave oscillator of the present invention.

FIG. 2 is a chip configuration diagram of a conventional stabilized monolithic microwave oscillator.

[Explanation of symbols]

 1 ... GaAs substrate 2 ... FET 3 ... Output terminal 4 ... Matching circuit 5, 10 ... Ground terminal 6 ... First feedback circuit 9 ... Second feedback circuit 7 ... Ceramic substrate 8 ... Transmission line 11 ... Resistor 12 ... Bonding wire 13 ... Bonding pad 15 ... Dielectric resonator 16 ... Drain bias terminal 17 ... Gate bias terminal 21 ... Drain 22 ... Source 23 ... Gate 26, 27 ... Bias line

Claims (2)

[Claims] 1. A FET is formed on a semi-insulating GaAs substrate,
A matching circuit is formed between the drain terminal and the output terminal of the FET, one end of which is connected to the ground terminal, the other end of which is connected to the source terminal of the FET, and one end of which is formed on the substrate. In the oscillator in which the other end of the second feedback circuit, which is connected to the ground terminal through the resistor being connected, is connected to the gate terminal of the FET, a dielectric resonator having predetermined electrical characteristics is provided on the GaAs substrate. A monolithic microwave oscillator, wherein the dielectric resonator is coupled to a transmission line provided between the second feedback circuit and the resistor. 2. A heterojunction bipolar transistor, a HEMT, or any other transistor is formed on a semi-insulating GaAs substrate, and a matching circuit is formed between the collector terminal and the output terminal of the transistor. A second feedback circuit in which the other end of the first feedback circuit connected to the ground terminal is connected to the emitter terminal of the transistor, and the one end of the terminal is connected to the ground terminal through a resistor formed on the substrate. In an oscillator in which the other end of the feedback circuit is connected to the base terminal of the transistor, a dielectric resonator having predetermined electric characteristics is provided on the GaAs substrate and provided between the second feedback circuit and the resistor. A monolithic microwave oscillator characterized in that the dielectric resonator is coupled to an existing transmission line.