JPH05218745A - Injection synchronization type push-push multiple oscillator - Google Patents

Abstract

PURPOSE:To eliminate the need for the connection of a band pass filter to an output of a high frequency band oscillator such as various radio equipments. CONSTITUTION:In the push-push oscillator 8 comprising a split ring resonator 5 and two negative resistance active circuits 8a, 8b whose characteristic is identical to each other connecting to the resonator, a fundamental wave is injected to the split ring resonator 5 via a coupling line 6 arranged in parallel with the split ring resonator 5 and outputs of the negative resistance active circuits 8a, 8b are synthesized by an in-phase synthesis circuit 9. Thus, a twice harmonic wave output is obtained at a high frequency output terminal 10, the fundamental wave component is suppressed and the band pass filter connecting to an output of the oscillator is made small or eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection-locking type push-push multiplication oscillator for various radio equipment for high frequency, communication equipment and the like.

[0002]

2. Description of the Related Art In recent years, the demand for mobile communication has rapidly increased, and a system using the quasi-microwave band has been developed as a new applicable frequency resource.

A conventional high frequency band oscillator will be described below. FIG. 3 shows the entire circuit configuration of a conventional high frequency band oscillator. In FIG. 3, 1 is a resonator section, 2 is an oscillator section having an oscillation circuit such as a Colpitts oscillation circuit, 3 is a frequency multiplier, and 4 is a band pass filter.

The operation of the high frequency band oscillator configured as described above will be described below. First, the oscillator 2 has a fundamental resonance frequency f ₀ determined by the resonator 1.
Oscillates at. Then, the doubled output 2f ₀ is obtained by the frequency multiplier 3 of the next stage, and the fundamental frequency f ₀ which is an unnecessary frequency component is attenuated by the bandpass filter 4 having a center frequency of 2f ₀ .

[0005]

However, in the above-mentioned conventional structure, the output of the normal fundamental wave component is much larger than the output of the second harmonic wave. Therefore, it is necessary to secure a large amount of attenuation of the filter at the fundamental frequency. However, there is a problem in that the filter cannot be downsized.

The present invention solves the above-mentioned problems of the prior art, and an object of the present invention is to provide a high frequency injection-locked push-push multiplication oscillator capable of downsizing or eliminating a filter connected to an oscillator output. To do.

[0007]

In order to achieve this object, the present invention provides a push-push oscillator comprising a resonator and two negative resistance active circuits having the same characteristic connected to the resonator. It has a configuration in which waves are injected and the outputs on the active circuit side are subjected to in-phase synthesis to take out a doubled wave.

[0008]

The present invention takes advantage of the fact that the two outputs of the push-push oscillator are the fundamental wave output in opposite phase and the second harmonic output in phase, and the outputs on the active circuit side are combined in phase to synthesize the second harmonic wave. It is possible to obtain the output and suppress the fundamental wave component, and it is possible to downsize or eliminate the bandpass filter connected to the oscillator output.

[0009]

(Embodiment 1) A first embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall configuration diagram of an injection locking type push-push multiplication oscillator in a first embodiment of the present invention. In FIG. 1, 5 is a split ring resonator, 6 is a parallel coupling line with the split ring resonator 5 that injects the fundamental wave f ₀ into the split ring resonator 5, 7 is a high frequency input terminal, and 8 is two identical characteristics. Negative resistance active circuit 8
A push-push oscillator composed of a and 8b, and 9 is a negative resistance active circuit 8a and 8b of the push-push oscillator 8.
A 0 ° hybrid circuit for in-phase combining two outputs is a high frequency output terminal.

The operation of the injection-locked push-push multiplier oscillator configured as described above will be described.

First, the parallel coupling line 6 is arranged such that the electrical length is equal to the left and right with respect to the high frequency grounding point of the split ring resonator 5, one end of the line is grounded, and the other end is the high frequency input terminal 7. .. Then, by applying the same high frequency signal as the basic resonance frequency f _{0 of the} resonator 5 to the input terminal 7, the push-push oscillator 8 is injection-locked to the oscillation frequency f ₀ via the resonator 5. At this time, since the split ring resonator is used as the resonator 5, the two outputs of the push-push oscillator 8 are in antiphase with the fundamental wave f ₀ and in phase with the second harmonic wave 2f ₀ , and the 0 ° hybrid combining circuit 9 Accordingly, only the second harmonic wave 2f ₀ is output to the high frequency output terminal 10, and the fundamental wave component f ₀ can be suppressed.

With the above configuration, it is possible to realize an oscillator in a high frequency band which does not require a bandpass filter which is conventionally required for an oscillator-multiplied output.

As described above, according to this embodiment, in the push-push oscillator 8 including the split ring resonator and the two negative resistance active circuits 8a and 8b connected to the split ring resonator, the resonator 5 is basically used. To realize a high-frequency band oscillator that does not require a band-pass filter by injecting waves and in-phase combining the outputs of the negative resistance active circuits 8a and 8b in the in-phase combining circuit 9 to extract a doubled wave. You can

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 shows a block connection diagram of a multiplication chain in the second embodiment of the present invention. In FIG. 2, 1
Reference numerals 1, 12, and 13 denote injection-locked push-push multiplier oscillators shown in the embodiment of FIG.

The operation of the multiplication chain configured as described above will be described below. First, a split ring resonator having a resonance frequency of f ₀ is used as a resonator forming the injection-locked push-push oscillator 11, and the fundamental wave f ₀ is suppressed by injecting the fundamental wave f ₀ through a parallel coupling line. Therefore, the output of only the second harmonic wave 2f ₀ can be taken out. Next, a split ring resonator having a resonance frequency of 2f ₀ is used as a resonator forming the injection-locked push-push oscillator 12, and the high-frequency output 2f ₀ of the oscillator 11 at the preceding stage is injected via the parallel coupled line, 2f ₀ is suppressed, and the output of only the second harmonic 4f ₀ can be extracted. Further, a split ring resonator having a resonance frequency of 4f ₀ is used as a resonator forming the injection-locked push-push oscillator 13, and the high-frequency output 4f ₀ of the oscillator 12 at the preceding stage is injected through the parallel coupled line to obtain 4f. ₀ is suppressed, and the output of only the second harmonic wave 8f ₀ can be taken out.

As described above, by connecting the injection-locked push-push oscillators in cascade, it is possible to realize a high-performance multiplication chain that does not require a filter.

[0019]

As described above, according to the present invention, in a push-push oscillator including a split ring resonator and two negative resistance active circuits connected to the split ring resonator, a fundamental wave is injected into the resonance circuit to activate the active circuit. By in-phase combining the outputs on the circuit side and extracting the second harmonic, an excellent injection-frequency-type push-push multiplier oscillator in a high frequency band that can reduce the band pass filter can be realized.

[Brief description of drawings]

FIG. 1 is a block connection diagram of an injection locking type push-push multiplication oscillator according to a first embodiment of the present invention.

FIG. 2 is a block connection diagram of a multiplication chain according to a second embodiment of the present invention.

FIG. 3 is a block diagram of a conventional high frequency band oscillator.

[Explanation of symbols]

 1 Resonator 2 Oscillation Circuit 3 Frequency Multiplier 4 Band Pass Filter 5 Split Ring Resonator 6 Coupling Line 7 High Frequency Input Terminal 8 Push-Push Oscillator 9 In-Phase Synthesis Circuit 10 High-Frequency Output Terminal 11 Injection-Locked Push-Push Multiply Oscillator 12 Injection-Locked Push-push multiplication oscillator 13 Injection-locked push-push multiplication oscillator

Claims (5)

[Claims] 1. A resonator, two negative resistance active circuits having the same characteristics, which are connected to the resonator, and a fundamental wave are injected into the resonator, and outputs of the active circuit side are combined in phase. Injection-push type push-push multiplication oscillator having an in-phase synthesizing circuit for extracting a second harmonic wave. 2. The injection-locked push-push multiplier oscillator according to claim 1, wherein a split ring resonator is used as the resonator, and an active circuit is provided at the two open ends of the split ring resonator. 3. The injection-locked push-push multiplier oscillator according to claim 2, wherein a capacitance is connected to the open end of the split ring resonator to finely adjust the frequency. 4. The injection locked push-push multiplier oscillator according to claim 2, wherein a variable capacitance is connected to the open end of the split ring resonator to form a wide band multiplier. 5. A multiplication chain is constructed by connecting push-push multiplication oscillators in cascade.
Injection-locked push-push multiplier oscillator described.