JPH0653743A - Injection synchronization type multiple oscillator - Google Patents

Abstract

PURPOSE:To realize a high efficiency oscillator for a high frequency band reducing the need for a band pass filter connecting to an output of the oscillator or eliminating the need for the filter with respect to the injection synchronization type multiple oscillator employed for various high frequency application radio equipment or the like. CONSTITUTION:The oscillator is provided with a frequency synthesizer 8, a broad band harmonic generator 9 comprising active element such as a transistor(TR), a split ring resonator 10 deciding the oscillating frequency of a push-push oscillator 12 and a push-push oscillator 12 comprising two negative resistance active circuits connecting to the resonator 10. Then the high efficiency oscillator for a high frequency band reducing the need for a band pass filter connecting to an output of the oscillator or eliminating the need for the filter is realized by using an in-phase synthesis circuit 13 to apply in-phase synthesis to outputs of the active circuit (oscillator 12) thereby extracting a double wave output.

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 multiplication oscillator used 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 systems using the quasi-microwave band which is a new applicable frequency resource have been developed.

A conventional high frequency band oscillator will be described below. FIG. 3 shows an entire circuit configuration of a conventional high frequency band oscillator. In FIG. 3, 1 is a resonator, 2
Are oscillators equipped with an oscillation circuit such as a Colpitts oscillation circuit, 3 and 5 are frequency multipliers, 4 and 6 are band pass filters, and 7 is a high frequency output terminal.

The operation of the high-frequency band oscillator configured as described above will be described below.

First, the oscillator 2 is determined by the resonator 1.
Fundamental resonance frequency f₀Oscillates at. And the next frequency
2f output 2f by the multiplier 3₀Get along with the heart
Frequency is 2f₀The bandpass filter 4 which is
Fundamental frequency f that is the wave number component ₀To attenuate. In the same way
2f output 4f by frequency multiplier 5₀And get
The center frequency is 4f₀To the bandpass filter 6 which is
2f, which is an unnecessary frequency component₀To attenuate the high frequency
External output from the power terminal 7 4f₀To get

[0006]

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, since the number of filter stages increases, it is not possible to realize miniaturization, and the external output (4f ₀ ) level is low.

The present invention solves the above-mentioned problems of the prior art, and an object of the present invention is to obtain a highly efficient high frequency band oscillator output while downsizing or eliminating a filter connected to the oscillator output.

[0008]

In order to achieve this object, the present invention provides a frequency synthesizer that changes an output frequency according to frequency setting information, and a wideband harmonic that generates a harmonic component from an output signal of the frequency synthesizer. A wave generator, a coupling circuit for injecting the output of the broadband harmonic generator into a resonator that determines an oscillation frequency, and a push-push oscillator including two negative resistance active circuits connected to the resonator, An in-phase combining circuit that combines the two outputs of the push-push oscillator in phase is provided.

[0009]

According to the present invention, the frequency synthesizer (f₀) Connect to output
Consisting of a transistor etc. as a continuous broadband harmonic generator
Low power consumption and efficient
Multiply output (N × f₀) Is taken out and the multiplied output is resonated.
Frequency N × f₀From the negative resistance active circuit through the resonator of
Pushing by inputting into the push-push oscillator
Oscillation frequency of push oscillator N × f₀Injection synchronized to negative
Output of active resistance active circuit side is combined by in-phase combining circuit
By doing so, the second harmonic output (2N × f ₀) Get
Together with the fundamental wave component (N × f₀) Can be suppressed
And a small bandpass filter connected to the oscillator output.
It can be shaped or deleted.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An 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 multiplication oscillator in one embodiment of the present invention. In FIG. 1, 8 is a frequency synthesizer which changes the output frequency according to the frequency setting information. Reference numeral 9 is a broadband harmonic generator, which has a resistance R
_{1 to} R ₄ , a transistor Tr, and a capacitor C ₂ . The front and rear C ₁ and C ₃ are capacitors for blocking DC components. Reference numeral 10 is a split ring resonator, 11 is a parallel coupling line with a resonator for injecting a broadband harmonic generator output into the split ring resonator 10, 12 is a push-push oscillator composed of two negative resistance active circuits, and 13 is a push-push oscillator. Reference numeral 14 denotes a high-frequency output terminal, which is an in-phase combining circuit composed of a 0 ° hybrid circuit for combining two outputs of the push oscillator in phase.

The operation of the injection-locked multiplication oscillator configured as above will be described. First, the output (f ₀ ) of the frequency synthesizer 8 is input to the broadband harmonic generator 9. By configuring the wideband harmonic generator 9 with an active element such as a transistor, a multiplied output (N × f ₀ ) can be efficiently taken out with a simple circuit and low current consumption. In addition, here, the doubled output (2f ₀ ) of the wideband harmonic generator 9 is taken out so that the operation can be easily understood.

Next, the frequency 2f₀Split that resonates with
The right and left sides of the ring resonator 10 are even
Arrange the parallel coupled line 11 so as to be patient and
Ground one end and input the output of the broadband harmonic generator 9 to the other end.
By pushing, push and push through the resonator 10
Oscillator 12 has oscillation frequency 2f₀Injection synchronized to. Injection in Figure 2
An example of the synchronization characteristics will be described. Output of frequency synthesizer 8
Force (f₀) 2f when the level is 0 dBm₀Sync range is about 8M
Both Hz and wideband characteristics can be obtained. On the other hand, a broadband harmonic generator
F included in the output of 9₀Since it does not resonate with the component,
From the push oscillator 12 f₀Is not output. this
At this time, the resonator 10 is a split ring type resonator 10.
By using two of the push-push oscillator 12
Output is 2f ₀Reverse phase, 2nd harmonic 4f₀It becomes the same phase at 0 °
High-frequency output terminal 1 by the in-phase in-phase synthesis circuit 13
4th double wave 4f₀Only output, 2f₀Can be suppressed
It In addition, the second harmonic 4f₀Is an in-phase combined output,
A double output level is obtained compared to the conventional frequency multiplier output.
Be done.

When a deviation occurs between the output frequency of the broadband harmonic generator 9 and the resonance frequency of the split ring type resonator 10, the injection locking characteristic deteriorates, as is apparent from FIG. It is possible to improve the characteristics by connecting a capacitor to the open end of the resonator 10 and finely adjusting the resonance frequency of the resonator. Furthermore, by making the capacitance connected to the open end of the split ring resonator a variable capacitance and having a voltage control configuration, it becomes possible to adjust the resonance frequency of the resonator by a control voltage from the outside.

By adopting the above configuration, the oscillator of the high frequency band of 2 × N times that of the frequency synthesizer can be miniaturized,
It can be realized with high efficiency and low power consumption.

As described above, according to the present embodiment, the frequency synthesizer 8 that changes the output frequency according to the frequency setting information, and the wideband harmonic generator 9 that receives the frequency synthesizer output signal as an input and generates the harmonic component are provided. Resonator 10 for determining the oscillation frequency of push-push oscillator 12
A parallel coupled line 11 for injecting the output of the broadband harmonic generator 9 into the resonator 10, and a push-push oscillator 12 including two negative resistance active circuits connected to the resonator 10.
And an in-phase combiner circuit 13 for in-phase combine the two outputs of the push-push oscillator 12, and by combining the outputs on the active circuit side in-phase to take out the second harmonic, a band pass filter is not required and high efficiency is achieved. It is possible to realize a high frequency band oscillator with a small size and low power consumption.

Although the multiplied output of the broadband harmonic generator 9 is doubled in the embodiment, it is not limited to this and a harmonic output of any order can be used. Further, although the resonator 10 is a split ring resonator, it goes without saying that it may be a normal half-wave resonator.

[0018]

As described above, according to the present invention, the frequency synthesizer for changing the output frequency according to the frequency setting information, the broadband harmonic generator for generating the harmonic component from the output signal of the frequency synthesizer, and the broadband A coupling circuit for injecting the output of the harmonic generator into a resonator that determines the oscillation frequency, a push-push oscillator including two negative resistance active circuits connected to the resonator, and a push-push oscillator. By providing an in-phase combining circuit for in-phase combining the outputs, the outputs on the active circuit side are combined in-phase to take out the second harmonic, so that it is highly efficient and can reduce or eliminate the band pass filter. It is possible to realize an oscillator.

[Brief description of drawings]

FIG. 1 is an overall block diagram of an injection-locked type multiplication oscillator according to an embodiment of the present invention.

FIG. 2 is an injection locking characteristic diagram of the injection locking type multiplication oscillator in the embodiment.

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

[Explanation of symbols]

 8 Frequency Synthesizer 9 Broadband Harmonic Generator 10 Resonator 11 Parallel Coupling Line 12 Push-Push Oscillator 13 In-Phase Synthesis Circuit 14 High-Frequency Output Terminal

Claims (5)

[Claims] 1. A frequency synthesizer for changing an output frequency according to frequency setting information, a wideband harmonic generator for generating a harmonic component from an output signal of the frequency synthesizer, and an output of the wideband harmonic generator, A coupling circuit for injecting into the resonator for determining the oscillation frequency, a push-push oscillator including two negative resistance active circuits connected to the resonator, and an in-phase combining circuit for in-phase combining the two outputs of the push-push oscillator. And an injection-locked multiplication oscillator. 2. The injection-locked multiplier oscillator according to claim 1, wherein the broadband harmonic generator has a circuit configuration using active elements. 3. A split ring resonator or a ½ wavelength resonator is used as the resonator, and a push-push oscillator composed of a negative resistance active circuit is provided at the two open ends of the resonator. Injection-locked multiplication oscillator. 4. The injection-locked multiplier oscillator according to claim 3, wherein a capacitance is connected to the open end of the resonator to finely adjust the resonance frequency of the resonator. 5. The injection-locked multiplier oscillator according to claim 3, wherein a voltage-controlled variable capacitor is connected to the open end of the resonator to control the voltage.