JPS6024001Y2 - microwave integrated circuit - Google Patents

Description

[Detailed Description of the Invention] (1) Technical Field of the Invention The present invention relates to microwave integrated circuits, and particularly to RF (Radio) circuits that supply DC power or low frequency signals.

Frequency) Concerning what forms a choke.

(2) Prior art and problems In the conventional oscillator in a microwave integrated circuit, for example, as shown in Fig. 1, a conductor 1 for a strip line is formed on a dielectric substrate, and one side of the conductor 1 oscillates. A Gunn diode 2, which is an element, is connected, and the conductor 3 of the line of λ/4 (λ is the wavelength of the required frequency) is branched, and the other end of the conductor 3 is connected with the line of input/2 centered at the other end. A conductor 4 is provided,
The conductor 3 and the conductor 4 form an RF choke that blocks a signal having a wavelength of λ, and a DC power supply 10 is applied from the RF choke to prevent the signal from being sucked into the power supply side.

Further, a notch 5 is provided in the middle of the conductor 1, and a directional coupler 6 is provided therein, and a dummy load resistor is installed at one end of the conductor 1 and the conductor 7 of the directional coupler 6 to prevent reflection. The membranes 8 and 9 are in contact with each other in a tapered manner, so that the microwave signal generated by the oscillation of the Gunn diode 2 is obtained from the end of the conductor 7 where there is no dummy load.

By the way, a Gunn diode with a large current has a limit in increasing the line impedance of the RF choke (in other words, making the conductor 3 thinner), and since the Gunn diode has negative resistance over a wide band, it is difficult to stabilize oscillation. In order to achieve this, it is necessary to suppress the influence of RF choke actance and make the band as wide as possible.

In the case of an oscillator like the one mentioned above, in order to avoid unnecessary oscillations, it is sufficient to see only the broadband dummy load (as is), but since the RF choke is an input/4 line, when viewed from the main line, the wavelength is The frequency f that becomes λ.

Since it does not appear to be completely open except for this, it appears to be parallel resonance.

The equivalent circuit of the load is as shown in FIG. 2, and the value of Q is Q□=Z0·BB=(ωC-7) from the capacitance C of the parallel resonance, the inductance L1, and the impedance 4 of the dummy load.

If Q is large (narrow band), the stabilizing resistance becomes small at frequencies other than fo, making it easier to oscillate at frequencies other than fo.

(3) Purpose of the invention The present invention was developed in view of the above circumstances.When forming an RF choke that supplies a DC power source or a low frequency signal, it is possible to form an RF choke over a wide band.
It is an object of the present invention to provide an improved microwave integrated circuit that reduces the influence of RF choke impedance over a wide band.

(4) Structure of the invention To distantly relate to the above object, the present invention provides a method for transmitting DC power or low frequency signals to a stripline conductor connected to an oscillation element on a dielectric substrate through an RF choke that blocks high frequency components. In a microwave integrated circuit configured to supply a dummy load, a conductor for the strip line is branched from a portion where the strip line is in contact with a resistive film serving as a dummy load in a tapered or step shape to form a front F choke. are doing.

(5) Embodiment of the invention Hereinafter, an embodiment of the invention will be described in detail with reference to the drawings.As shown in FIG. 3, a Gunn diode 2,
The conductor 3' of the input/4 line is branched from the part of the conductor 1 having the directional coupler 6 that is in tapered contact with the resistive film 8, and the conductor 3' of the input line 3' is branched off from the part of the conductor 1 having the directional coupler 6 that is in tapered contact with the resistive film 8. An RF choke is formed by the conductor 3 and the conductor 4, and a DC power source 10' is applied from the RF choke.

In this way, DC power is supplied from a location where the RF signal is attenuated by the resistive film, so even at a location far away from the frequency, there are few reflected components due to the RF choke, and the dummy load can be clearly seen.

Furthermore, according to the present invention, since the RF choke is formed from the middle of the dummy load, a resistance component is introduced before the RF choke, resulting in an equivalent circuit as shown in FIG.

In this), the resistance on the side of the directional coupler from the midpoint where the RF choke is connected is R1, the resistance after the midpoint of the RF choke is R2, and K '' R1/R2, at the resonant frequency of the pressure. If we set 4=R□+R2 as a matching condition, then R22 Q=R2+K(BH3)2+t)''.

For example, in the case of Fig. 2, let Q be Q engineering and set the condition as K =
Let IB=IZO=1.

Also, assuming Q in the case of Fig. 4 as Q2, R1=R2=0.
58 = IZo = 1, then Q2/Qi =
0.222, and the value of Q is lower in the present invention.

It can be seen that this results in a wide band as shown by the solid line in FIG.

Therefore, the influence of the impedance of the RF choke is reduced over a wide band.

Another embodiment of the invention is shown in FIG.

In FIG. 6, a resistive film 8' is formed stepwise in the axial direction of the strip line 1 in units of length λ4 to form a dummy load.

(6) Effects of the invention As described above, according to the invention, the influence of the impedance of the RF choke is reduced over a wide band, making it possible to obtain stable micro-oscillation signals and the like.

The present invention can also be applied to supplies of low frequency signals other than oscillators, and the resistive film may be brought into contact with the conductor of the strip line in a stepped manner.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing a conventional oscillator, Fig. 2 is its equivalent circuit diagram, Fig. 3 is a circuit diagram showing an embodiment of the present invention, and Fig. 4 is a circuit diagram showing a conventional oscillator.
The figure is an equivalent circuit diagram, FIG. 5 is a diagram showing the relationship between frequency and standing wave ratio, and FIG. 6 is a diagram showing another embodiment. 1... Conductor for strip line, 2...
Gunn diode, 3, 3', 4, 4'...RF
Blocking circuit conductor, 5... Notch, 6...
・Directional coupler, 7... Curved conductor, 8, 9... Resistive film, 10, 10'... DC power supply, 11...
...Stripline resonator.

Claims (1)

[Scope of utility model registration request] In a microwave integrated circuit in which a DC power supply or a low frequency signal is supplied to a strip line conductor connected to an oscillation element on a dielectric substrate through an RF choke that blocks high frequency components, the strip line is a dummy conductor. RF
A microwave integrated circuit characterized by its shape as a choke.