^44 57 2 1 五、發明說明α) 發明之背景 1. 發明之領域 本發明係關於一種壓控振盪器自由振盪時之直流偏壓電 源雜訊抑制方法，尤其是關於一種在壓控振盪器自由振盪 時用以抑制一供應給壓控振盪器之直流偏壓電源所耦合的 交流雜訊的直流偏壓電源雜訊抑制方法。 2. 先前技藝之說明 目前在量測壓控振盪器自由振盪時之輸出信號的相位雜 訊之方法大多是直接使用直流電源供應器來提供直流偏壓 電源"藉由該直流偏壓電源之輸入，在壓控振盪器内部之 可調變電容器二極體的電極板間，將產生一直流電場偏 壓，使得該可調變電容器二極體產生相對應的電容值，進 而於壓控振盪器之輸出端輸出一依該電容值而定的振盪信 號。 但是，直流電澈供應器所提供之直流偏壓電源往往伴隨 著耦合的交流雜訊，該交流雜訊會使得壓控振盪器内部之 可調變電容器二極體的電極板間，產生不穩定的交流電場 偏壓，進而使該可調變電容器二極體的電容值不穩定。結 果，如圖1所示，壓控振盪器自由振盪時之輸出信號將發 生頻率擾動的現象，這是因為此時所量測出的壓控振盪器 自由振盪時之輸出信號的相位雜訊，含混著直流電源供應 器所提供的交流雜訊之故。 因此，為了獲得壓控振盪器在自由振盪時之一較準確的 輸出信號相位雜訊，大多是使用乾電池或蓄電池作為直流^ 44 57 2 1 V. Description of the invention α) Background of the invention 1. Field of the invention The present invention relates to a method for suppressing noise of a DC bias power supply when a voltage controlled oscillator is freely oscillating, and more particularly to a voltage controlled oscillator A DC bias power source noise suppression method for suppressing AC noise coupled to a DC bias power source supplied to a voltage controlled oscillator during free oscillation. 2. Description of the prior art At present, most methods for measuring the phase noise of the output signal when the voltage-controlled oscillator is freely oscillating are mostly directly using a DC power supply to provide a DC bias power supply. The input, between the electrode plates of the adjustable capacitor diode inside the voltage-controlled oscillator, will generate a DC electric field bias voltage, so that the adjustable capacitor diode will have a corresponding capacitance value, which will further affect the voltage-controlled oscillation. The output terminal of the device outputs an oscillating signal determined by the capacitance value. However, the DC bias power provided by the DC power supply is often accompanied by coupled AC noise. This AC noise will cause unstable voltage between the electrode plates of the adjustable capacitor diodes inside the voltage controlled oscillator. The AC electric field bias causes the capacitance of the tunable capacitor diode to become unstable. As a result, as shown in FIG. 1, the frequency disturbance of the output signal of the voltage-controlled oscillator during free oscillation will occur. This is because the phase noise of the output signal of the voltage-controlled oscillator during free oscillation measured at this time, Contains AC noise from a DC power supply. Therefore, in order to obtain a more accurate phase noise of the output signal when the voltage-controlled oscillator is in free oscillation, most of them use dry batteries or batteries as DC.
第4頁 ^44 57 2 1 五、發明說明（2) 電壓源裝置，俾提供一比直流電源供應器較為純淨且穩定 的直流偏壓電源，進而在壓控振盪器内部可調變電容器二 極體的電極板間，產生一穩定直流電場偏壓，以使該可調 變電容器二極體產生相對應的穩定電容值，俾自由振盪出 一具穩定頻率的信號》其結果如圖2所示，可看到其輸出 頻率穩定多了 。又，此時所量測出之有關壓控振盪器在自 由振盪時之輸出信號的相位雜訊即為壓控振盪器自由振盪 時的本質相位雜訊。 然而，使用乾電池或蓄電池作為直流電壓源裝置有很大 的缺點，此一方面是因為乾電池或蓄電池的輸出直流電壓 固定而無法提供任意電壓值的直流電壓；另一方面是因為 在量測壓控振盈器自由振盪時之輸出信號的相位雜訊時， 不同廠牌型號的壓控振盪器需要不同的直流偏壓電源，以 調整壓控振盪器自由振盪時之輸出信號的頻率，而乾電池 或蓄電池之輸出直流電壓值固定的特性，反而造成量測壓 控振盪器自由振盪時輸出信號相位雜訊的不便利，甚至於 無法量測。 發明之概述 本發明之一目的在於提供一種可以簡單地在壓控振盪器 自由振盪時抑制一供電給壓控振盪器之直流偏壓電源所耦 合的交流雜訊的方法，藉以改善壓控振盪器在自由振盪時 之輸出訊號的相位雜訊。 本發明之另一目的在於增進壓控振盪器進行品質測試.時之 準確性。Page 4 ^ 44 57 2 1 V. Description of the invention (2) The voltage source device provides a purer and more stable DC bias power supply than a DC power supply, which can then adjust the capacitor pole in the voltage-controlled oscillator. A stable DC electric field bias is generated between the electrode plates of the body, so that the tunable capacitor diode has a corresponding stable capacitance value, and freely oscillates a signal with a stable frequency. The result is shown in Figure 2. , You can see that its output frequency is much more stable. In addition, the phase noise of the output signal of the voltage-controlled oscillator during free oscillation measured at this time is the essential phase noise of the voltage-controlled oscillator during free oscillation. However, the use of dry batteries or accumulators as a DC voltage source device has great disadvantages. On the one hand, this is because the output DC voltage of the dry batteries or accumulators is fixed and cannot provide a DC voltage of any voltage value. When the phase noise of the output signal when the oscillator is freely oscillating, different brands of voltage-controlled oscillators require different DC bias power sources to adjust the frequency of the output signal when the voltage-controlled oscillator is freely oscillating. The characteristic that the output DC voltage value of the battery is fixed, instead, it is inconvenient to measure the phase noise of the output signal when the voltage-controlled oscillator is free to oscillate, and it is even impossible to measure. SUMMARY OF THE INVENTION An object of the present invention is to provide a method for improving the voltage-controlled oscillator by simply suppressing AC noise coupled to a DC bias power supply to the voltage-controlled oscillator when the voltage-controlled oscillator is freely oscillating. Phase noise of the output signal during free oscillation. Another object of the present invention is to improve the accuracy of the voltage-controlled oscillator for quality testing.
^ 44 57 2 1 五、發明說明（3) 為達成上述目的，本發明所揭之壓控振盪器自由振盪時 直流偏壓電源雜訊抑制方法具特徵在於：在一用以供應直 流偏壓電源的直流電壓源裝置之輸出端，與該壓控振盪器 之一可受該直流偏壓電源控制的可調變電容器二極體之 間，串接一電阻。 藉·由上述方法，將可以抑制直流電壓源裝置於輸出直流 偏壓電源時所伴隨耦合之交流雜訊，而明顯改善壓控振盪 器在自由振盪時之輸出信號的相位雜訊，進而提升壓控振 盪器之測試準喊性。 圖式之簡單說明 圖1為一習知直接使用直流電源供應器提供直流偏壓電 源時在壓控振.盪器自由振盪時所量測得之輸出信號的相位 雜訊圖。 圖2為一習知直接使用乾電池提供直流偏壓電源時在壓 控振盪器自由振盪時所量測得之輸出信號的相位雜訊圖。 圖3為一根據本發明而成之雜訊抑制方法之實施態樣示 意圖。 圖4為一依圖3所示實施態樣且直流電壓源裝置為電源供 應器而所串接電阻之電阻值為10歐姆時在壓控振盪器所量 測得之輸出信號的相位雜訊圖。 圖5為一依圖3所示實施態樣且直流電壓源裝置為電源供 應器而所串接電阻之電阻值為100歐姆時¥壓控振盪器所 量測得之輸出信號的相位雜訊圖。 圖6為一依圖3所示實施態樣且直流電壓源裝置為電源供^ 44 57 2 1 V. Description of the invention (3) In order to achieve the above object, the method for suppressing noise of a DC bias power supply during free oscillation of the voltage controlled oscillator disclosed in the present invention is characterized by: A resistor is connected in series between the output terminal of the direct-current voltage source device and one of the voltage-controlled oscillator's adjustable capacitor diodes which can be controlled by the direct-current bias power supply. By the method described above, the AC noise coupled with the DC voltage source device when outputting a DC bias power supply can be suppressed, and the phase noise of the output signal of the voltage controlled oscillator during free oscillation is significantly improved, thereby increasing the voltage. Controlled oscillator test accuracy. Brief Description of the Drawings Figure 1 is a phase noise figure of an output signal measured when a voltage-controlled oscillator is freely oscillated when a direct-current DC power supply is used to provide DC bias power. FIG. 2 is a phase noise diagram of an output signal measured when a voltage-controlled oscillator is freely oscillating when a conventional dry battery is used to provide a DC bias power. Fig. 3 is a schematic diagram showing an implementation of a noise suppression method according to the present invention. 4 is a phase noise figure of an output signal measured by a voltage-controlled oscillator when the DC voltage source device is a power supply and the resistance value of the series resistor is 10 ohms according to the implementation shown in FIG. 3 . FIG. 5 is a phase noise figure of an output signal measured when a voltage-controlled oscillator is used when a DC voltage source device is a power supply and the resistance value of the series resistor is 100 ohms according to the implementation shown in FIG. . FIG. 6 shows an embodiment according to FIG. 3 and the DC voltage source device is a power supply.
445721 五、發明說明（4) 應器而所串接電阻之電阻值為lk歐姆時在壓控振盪器所量 測得之輸出信號的相位雜訊圖。 圖7為一依圖3所示實施態樣且直流電壓源裝置為乾電池 而所串接電阻之電阻值為1 〇 〇歐姆時在壓控振盪器所量測 得之輸出信號的相位雜訊圖。 圖式符號之說明 1壓控振盪器 .2直流電壓源裝置 3電阻 12可調變電容二極體 發明之詳細說明 圖3顯示一根據本發明而成之雜訊抑制方法之實施態樣 示意圖。如圖3所示，本發明所揭之雜訊抑制方法適用於 一接受一直流電壓源裝置2之直流偏壓電源而輸出一相對 應之振盪信號輸出的壓控振盪器1 ;其中，該壓控振盪器1 具有一可調變電容二極體12，該可調變電容二極體12具有 一對電極板；該直流電壓源裝置2可為一電池或一直流電 源供應器，其輸出一直流偏壓電源，並使其經該依據本發 明而設之電阻3後，才送給該可調變電容二極體12之電極 板，俾使該可調變電容二極體1 2受到偏壓而產生相對應的 穩定電容值，進而使壓控振盪器1依該電容值輸出一對應 之振盪信號° 藉由上述構成，由於可調變電容二極體12可以導通交流 電，因而直流電壓源裝置2，尤其是電源供應器，所輸出 之直流偏壓電源所耦合之交流雜訊會通過電阻3，且其能 量會被電阻3所損耗，使得該壓控振盪器1中之可調變電容445721 V. Description of the invention (4) Phase noise figure of the output signal measured by the voltage-controlled oscillator when the resistance value of the resistor connected in series is lk ohm. FIG. 7 is a phase noise diagram of an output signal measured by a voltage-controlled oscillator when the DC voltage source device is a dry battery and the resistance value of the series resistor is 100 ohms according to the embodiment shown in FIG. 3. . Explanation of figure symbols 1 Voltage-controlled oscillator. 2 DC voltage source device 3 Resistance 12 Adjustable variable capacitor diode Detailed description of the invention FIG. 3 shows a schematic diagram of an embodiment of a noise suppression method according to the present invention. As shown in FIG. 3, the noise suppression method disclosed in the present invention is applicable to a voltage-controlled oscillator 1 that receives a DC bias power source of a DC voltage source device 2 and outputs a corresponding oscillating signal output; The controlled oscillator 1 has an adjustable variable capacitance diode 12 having a pair of electrode plates. The DC voltage source device 2 can be a battery or a DC power supply, and its output is always After biasing the power supply and passing it through the resistor 3 provided according to the present invention, it is sent to the electrode plate of the variable capacitance capacitor 12 to bias the variable capacitance capacitor 12 Voltage to generate a corresponding stable capacitance value, so that the voltage-controlled oscillator 1 outputs a corresponding oscillating signal according to the capacitance value. With the above configuration, since the variable-capacitance diode 12 can conduct AC power, a DC voltage source Device 2, especially the power supply, the AC noise coupled by the output DC bias power will pass through the resistor 3, and its energy will be lost by the resistor 3, so that the adjustable capacitance in the voltage controlled oscillator 1
445721 五、發明說明（5) 二極體1 2的電極板間因該交流雜訊而產生不穩定的交流電 場偏壓會受到抑制，進而使該可調變電容二極體1 2之電容 值可以維持穩定；結果，壓控振盪器1在自由振盥時所輸 出之振盪信號即不受所耦合之交流雜訊的影響而具有相當 穩定之頻率，進而達到抑制直流電源供應器所輸出之直流 偏壓電源所伴隨耦合的交流雜訊的目的。此時所量測出壓 控振盪器之輸出信號的相位雜訊乃是壓控振盪器自由振盪 時之本質相位雜訊。 又，對於直流偏壓電源本身而言，由於可調變電容二極 體1 2形同斷路，因而不會有直流電流流經電阻3，亦即電 阻3對於直流偏壓電源不會造成電壓降，因而電阻3之串接 對於所欲供電之直流偏壓電源不會有不良影響。 圖4為一依上述實施態樣，且直流電壓源裝置2為電源供應 器，而其輸出電壓為1.48伏特且所串接電阻之電阻值為10 歐姆時，在壓控振盪器之輸出端所量測得之壓控振盪器自 由振盪時之輸出信號的相位雜訊圖。由圖4所示可以發 現，當所串接之電阻值只有1 0歐姆時，其輸出信號的相位 雜訊在低頻部分，仍有明顯的擾動現象，但在高頻部分則 改善良多。 圖5為一依上述實施態樣且直流電壓源裝置2為電源供應 器而所串接電阻之電阻值為100歐姆時之壓控振盪器自由 振盪時之輸出信號的相位雜訊圖。由圖5所示可以發現， 當所串接之電阻值為1 0 0歐姆時，其輸出信號的相位雜訊 不管是在低頻部分或高頻部分 > 都改善良多。這是因為直445721 V. Description of the invention (5) The unstable AC electric field bias voltage generated between the electrode plates of the diode 12 due to the AC noise will be suppressed, thereby making the capacitance value of the adjustable capacitor diode 12 It can maintain stability; as a result, the oscillating signal output by the voltage-controlled oscillator 1 during free vibration is not affected by the coupled AC noise and has a fairly stable frequency, thereby suppressing the DC output from the DC power supply. The purpose of AC noise coupled with bias power. The phase noise of the output signal of the voltage-controlled oscillator measured at this time is the essential phase noise when the voltage-controlled oscillator oscillates freely. In addition, for the DC bias power supply itself, since the adjustable capacitor diode 12 is shaped like an open circuit, no DC current flows through the resistor 3, that is, the resistor 3 does not cause a voltage drop to the DC bias power supply. Therefore, the series connection of resistor 3 will not have an adverse effect on the DC bias power supply to be supplied. FIG. 4 shows a state according to the above embodiment, and the DC voltage source device 2 is a power supply, and its output voltage is 1.48 volts and the resistance value of the series resistor is 10 ohms. Phase noise figure of the measured output signal of the voltage-controlled oscillator during free oscillation. As shown in Figure 4, it can be found that when the resistance value connected in series is only 10 ohms, the phase noise of the output signal is still obvious in the low frequency part, but it is improved a lot in the high frequency part. Fig. 5 is a phase noise diagram of an output signal when the voltage-controlled oscillator is freely oscillating when the DC voltage source device 2 is a power supply and the resistance value of the series resistor is 100 ohms according to the above embodiment. It can be found from FIG. 5 that when the resistance value connected in series is 100 ohms, the phase noise of the output signal is improved a lot whether it is in the low frequency part or the high frequency part. This is because straight
44572 1 五、發明說明（6) 流偏壓電源所耦合之交流雜訊被抑制了 ，壓控振盪器在自 由振盪時所輸出之振盪信號的相位雜訊因而減少之故。進 而在直流電壓源裝置2所耦合之交流雜訊被抑制之下，將 能更準確地量測出壓控振盪器自由振盪時其本身輸出信號 的相位雜訊。 圖6為一依上述實施態樣且直流電壓源裝置2為電源供應 器而所串接電阻之電阻值為1000歐姆時之壓控振盪器自由 振盪時之輸出信號的相位雜訊圖。由圖6所示可以發現， 壓控振盪器自由振盪時之輸出信號的相位雜訊與圖5所示 者幾乎相同13 由上述情形可推得該電阻3確實具有特殊效果，尤其在 所串接之電阻在1〇〇歐姆以上時更具效果。 圖7為一依上述實施態樣且直流電壓源裝置2為乾電池而 所串接電阻之電阻值為100歐姆時之壓控振盪器自由振盪 時之輸出信號的相位雜訊圖。由圖7所示可以發現，雖然 習知使用乾電池已能獲得一相當穩定之信號輸出，但若亦 串接一電阻於壓控振盪器1與乾電池之間的話，亦能獲得 一更佳之輸出（少了高頻部分之一些偽波）；因此，不管該 直流電壓源裝置2係電源供應.器或乾電池或蓄電池，本發 明所揭技術思想都可適用" 惟，上述以及圖式所揭方法僅為一最佳實施例，各種熟 於此技藝人士在參照所揭内容下之任何不脫離所附申請專 利範圍所作之變形應皆在保護範圍内。44572 1 V. Description of the invention (6) The AC noise coupled with the current bias power is suppressed, and the phase noise of the oscillation signal output by the voltage controlled oscillator during free oscillation is reduced. Further, under the suppression of the AC noise coupled by the DC voltage source device 2, the phase noise of the output signal of the voltage controlled oscillator when it is freely oscillating can be measured more accurately. FIG. 6 is a phase noise diagram of an output signal when the voltage-controlled oscillator in the DC voltage source device 2 is a power supply and the resistance value of the series resistor is 1000 ohms in free oscillation according to the above embodiment. It can be found from Figure 6 that the phase noise of the output signal of the voltage-controlled oscillator during free oscillation is almost the same as that shown in Figure 5. 13 From the above situation, it can be concluded that the resistor 3 does have a special effect, especially when connected in series. When the resistance is more than 100 ohms, it is more effective. FIG. 7 is a phase noise diagram of an output signal when the voltage-controlled oscillator in the DC voltage source device 2 is a dry battery and the resistance value of the series resistor is 100 ohms according to the above embodiment when the voltage-controlled oscillator is freely oscillating. It can be found from FIG. 7 that although the conventional use of dry batteries has been able to obtain a fairly stable signal output, if a resistor is also connected in series between the voltage controlled oscillator 1 and the dry battery, a better output can also be obtained ( (There are some pseudo waves in the high-frequency part); therefore, regardless of the DC voltage source device 2 series power supply device or dry battery or accumulator, the technical idea disclosed in the present invention can be applied " It is only a preferred embodiment, and any deformation made by those skilled in the art with reference to the disclosed content without departing from the scope of the attached patent application shall be within the protection scope.