TW519802B - Radio communication system for depressing mid-band false image interference - Google Patents
Radio communication system for depressing mid-band false image interference Download PDFInfo
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519802 五、發明說明（1) 發明領域： 本發明係有關於一種無線通訊系統，更詳而言之，係有 關於一種抑制中頻假像干擾之無線通訊系統，在VHF頻段 1 6 0 Mhz〜3 0 0 Mhz環境中，於操作時可有效地抑制中頻假像干 擾，具有較佳之頻率響應，而能有效地避免中頻假象干擾問 題0 發明背景： 一般習知的VHF接收系統，如第1圖中所示，接收系統2 之高頻調諧器3含有天線3 1、高頻放大器3 2、混波器3 3、 以及本地振盪器34。天線31負責接收VHF之無線電磁波訊 號，並將所接收到的感應訊號傳送到高頻放大器3 2以進行 ^波、放大處理。高頻放大器32通常使用在混%皮器33之 Ϊ，礙W改^\超高頻率接收系統之信號—雜訊比（S/N)。此 員 抑糸統主要將完成把希望接收 予以濾波及適當放大。 项手^ ”自，丹 弟2圖為第1圖中之v g卩夕古 / 譜圖。如圖中所示，假象 鬲頻接收系統的頻率響應頻 4Mhz，由頻譜展示可知只‘頻率和預期接收頻率差為21 · 接收系統而言，無法有^ : 87dbm，對習知的VHF頻段之 有較差之頻率響應問題 卩制頻率假象干擾問題，以及具 乃疋待解決的。 發明概述與目 本發明之主要目的便 於提供一種抑制中頻假像干519802 V. Description of the invention (1) Field of the invention: The present invention relates to a wireless communication system, and more specifically, to a wireless communication system for suppressing intermediate frequency artifacts, in the VHF band 16 0 Mhz ~ In 3 0 0 Mhz environment, it can effectively suppress IF artifact interference during operation, have better frequency response, and effectively avoid the problem of IF artifact interference. 0 BACKGROUND OF THE INVENTION: Generally known VHF receiving systems, such as As shown in FIG. 1, the high-frequency tuner 3 of the receiving system 2 includes an antenna 3 1, a high-frequency amplifier 3 2, a mixer 3 3, and a local oscillator 34. The antenna 31 is responsible for receiving VHF wireless electromagnetic wave signals, and transmitting the received induction signals to the high-frequency amplifier 32 for wave and amplification processing. The high-frequency amplifier 32 is usually used in the mixer 33, which hinders the signal-to-noise ratio (S / N) of the ultra-high frequency receiving system. This member system will mainly finish filtering and appropriately amplifying the desired reception.手 手 ^ ”Since, Dandi 2 is the vg 卩 Xigu / spectrum in the first picture. As shown in the figure, the frequency response frequency of the pseudo-audio receiving system is 4Mhz. From the spectrum display, we can only know the frequency and expectation. Receiving frequency difference is 21. For receiving systems, there is no ^: 87dbm, and the problem of poor frequency response to the conventional VHF frequency band is to control the problem of frequency artifacts, and it is to be solved. SUMMARY OF THE INVENTION The main purpose of the invention is to provide a method for suppressing intermediate frequency artifacts.
第4頁 519802 五、發明說明（2) 擾之無線通訊系統，應用於VHF環境中，於操作時可有效地 抑制中頻假像干擾。 本發明之另一目的便是在於提供，一種抑制中頻假像 干擾之無線通訊系統，應用於VHF環境中，可提高所需選擇 頻寬之+ dbm功率值，使得天線所接收之感應訊號經由濾波 器而到放大器時，其選擇頻寬能變窄，使得於同樣之仳；；值 的環境下，能期望接收頻率之頻寬變窄，具有較佳之頻率燮 應頻譜和選擇性，而能有效地避免中頻假象干擾問題。曰 根據以上所述的目的，本發明提供了一種新穎之一種 抑制中頻假像干擾之無線通訊系統，應用於VHF環境中，可 提高所需選擇頻寬之+ dbm功率值，使得天線所接收之感應 號經由濾波器而到放大器時，其選擇頻寬能變窄，使得於 同樣之dbm值的環境下，能期望接收頻率之頻寬變窄具; 較佳之頻率響應頻譜和選擇性，而能有效地避免中頻^ 干擾問題。 & 本發明之抑制中頻假像干擾之無線通訊系統包含天線 模組、第一濾波器模組、前級低雜訊放大器模組、以 二濾波器模組。 矛 、天線模組負責接收VHF頻率的無線訊號，並將所接收之 感應訊號傳送至第一濾波器模組，以進行慮波處理。 第一渡波器模組將對來自天線模組之感應訊號做濾波 處理，以將不必要的雜訊予以濾掉。在無線訊號接收系^先 中，以調諧電路選取所需的信號頻率。第一濾波器模組將 處理後之訊號傳送給放大器模組，以進行放大作用。Page 4 519802 V. Description of the invention (2) The interference wireless communication system is applied in the VHF environment, which can effectively suppress the intermediate frequency artifact interference during operation. Another object of the present invention is to provide a wireless communication system for suppressing IF artifact interference, which is applied in a VHF environment, and can increase the required selected bandwidth + dbm power value, so that the induction signal received by the antenna passes When the filter arrives at the amplifier, its selection bandwidth can be narrowed to make it the same; under the environment of value, the bandwidth of the receiving frequency can be expected to be narrower, which has better frequency response spectrum and selectivity, and can Effectively avoid the problem of intermediate frequency artifacts. According to the above-mentioned purpose, the present invention provides a novel wireless communication system for suppressing IF artifact interference, which is applied in a VHF environment, and can increase the required selected bandwidth + dbm power value, so that the antenna receives When the induction number reaches the amplifier through the filter, its selection bandwidth can be narrowed, so that under the same dbm value environment, the bandwidth of the receiving frequency can be expected to be narrower; better frequency response spectrum and selectivity, and Can effectively avoid the problem of IF ^ interference. & The wireless communication system for suppressing intermediate frequency artifacts of the present invention includes an antenna module, a first filter module, a pre-stage low noise amplifier module, and a two filter module. The spear and antenna modules are responsible for receiving wireless signals at the VHF frequency, and transmitting the received induction signals to the first filter module for wave consideration processing. The first wavelet module will filter the inductive signal from the antenna module to filter out unnecessary noise. In the wireless signal receiving system, the required signal frequency is selected by the tuning circuit. The first filter module sends the processed signal to the amplifier module for amplification.
第5頁 519802Page 5 519802
五、發明說明（3) 放大器模組接收到經由第一濾波器模組 後，將訊號予以放大，並將放大後的訊號傳送 模組，以進行第二次訊號濾波處理。 第二濾波器模組接收到經放大器模組處 後，將對訊號進行第二次濾波處理，並將處理 給後續之混波器，以進行處理。 處理後之 到第二濾 訊號 波器 理完之訊號 後之訊號傳送 利用本發明之抑制中頻假像干擾之無線^ ^ / VHF頻段1 6〇Mhz〜3 0 0Mhz環境中，於操作時可右J ·糸統，在 頻假像干擾，並提高所需頻寬之正增益dbm功率& ^中 線所接收之感應訊號經由濾波器而到放大器時 ^ $得天 寬能變窄，使得於同樣之正dbm值的環境下，預計^選擇頻 之頻寬變窄，使具有較佳之選擇性頻率響應，而5如+收頻率 免中頻假象干擾問題。 又地避 圖示簡述: 為讓本發明之上述和其它目的，特徵，優點能更 懂，將舉較佳實施例，並配合所附圖示，詳細說明本發日顯易 實施例，所附圖式之内容簡述如下： X明之 弟1圖為一系統方塊圖，其中顯示習知的V H F接收系統的 本糸統硬體組織架構； > ' 第2圖為帶通濾波振幅頻率響應圖，用以顯示如第i圖中 接收系統的帶通渡波器頻譜圖； ° 第3圖為一糸統方塊圖，其中顯不本發明之抑制中頻{厂 擾之無線通訊系統的基本系統硬體組織架構，並釦士又^象干 u尽地振V. Description of the invention (3) After receiving the first filter module, the amplifier module amplifies the signal and transmits the amplified signal to the module for the second signal filtering process. After the second filter module receives the signal from the amplifier module, it will perform a second filtering process on the signal and process it to the subsequent mixer for processing. The signal transmission after processing to the signal processed by the second filter wave filter utilizes the wireless ^ ^ / VHF band of 160 MHz to 300 MHz in the VHF band of the present invention, which can be used during operation. Right J · system, in the frequency artifact interference, and increase the required bandwidth of the positive gain dbm power & ^ when the inductive signal received by the center line to the amplifier through the filter ^ $ the width can be narrowed, making Under the same environment with a positive dbm value, it is expected that the bandwidth of the selected frequency will be narrowed, so that it has a better selective frequency response, and 5 such as + receiving frequency to avoid the problem of intermediate frequency artifacts. In order to make the above and other objects, features, and advantages of the present invention more comprehensible, preferred embodiments will be given in conjunction with the accompanying drawings to explain in detail the easy-to-execute embodiments of the present day. The contents of the drawings are briefly described as follows: Figure 1 of X Ming is a system block diagram showing the hardware structure of the conventional VHF receiving system; > 'Figure 2 is the band-pass filtering amplitude frequency response Figure, used to show the frequency spectrum of the bandpass wave-receiver of the receiving system as shown in Figure i; ° Figure 3 is a block diagram of the system, which shows the basic system hardware Physical organization structure
519802 五、發明說明（4) 盪器配合的情形； 第4圖為一電路圖，其中顯示LC並聯諧振電路的電路架構； 第5圖為一電路圖，其中顯示電容抽頭阻抗轉換電路的電路 架構； 第6圖為一電路圖，其中顯示雙調諧變壓器耦合電路的電路 架構； 第7圖為一頻譜分析圖，其中顯示不同之耦合係數的頻譜分 析；519802 V. Description of the invention (4) The situation of the cooperation of the oscillator; Figure 4 is a circuit diagram showing the circuit architecture of the LC parallel resonant circuit; Figure 5 is a circuit diagram showing the circuit architecture of the capacitor-tap impedance conversion circuit; Figure 6 is a circuit diagram showing the circuit architecture of the dual-tuned transformer coupling circuit; Figure 7 is a spectrum analysis diagram showing the spectrum analysis of different coupling coefficients;
第8圖為一系統方塊圖，其中顯示本發明之抑制中頻假像干 擾之無線通訊系統的第一濾波器模組的一實施例的電路 圖； 第9圖為一系統方塊圖，其中顯示本發明之抑制中頻假像干 擾之無線通訊系統的第二濾波器模組的一實施例的電路 圖； 第1 0圖為帶通濾波振幅頻率響應圖，用以顯示本發明之抑 制中頻假像干擾之無線通訊系統的帶通濾波器頻譜圖； 第1 1圖為實體電路圖，用以顯示本發明之抑制中頻假像干 擾之無線通訊系統的帶通濾波器之一實施例，於印刷電路 板上實施的實際排列方式；以及FIG. 8 is a system block diagram showing a circuit diagram of an embodiment of a first filter module of the wireless communication system for suppressing IF artifact interference of the present invention; FIG. 9 is a system block diagram showing the present The circuit diagram of an embodiment of the second filter module of the wireless communication system for suppressing IF artifact interference of the invention; FIG. 10 is a band-pass filtering amplitude frequency response diagram for showing the IF artifact suppression of the invention Spectrum diagram of the bandpass filter of an interfering wireless communication system; Figure 11 is a physical circuit diagram showing an embodiment of the bandpass filter of the wireless communication system for suppressing IF artifact interference according to the present invention. The actual arrangement implemented on the board; and
第1 2圖為實體電路圖，用以顯示本發明之抑制中頻假像干 擾之無線通訊系統的帶通濾波器之另一實施例，於印刷電 路板上實施的實際排列方式。Fig. 12 is a physical circuit diagram showing the actual arrangement of the band-pass filter of the wireless communication system for suppressing IF artifact interference according to another embodiment of the present invention implemented on a printed circuit board.
第7頁 519802 五、發明說明（5) ^^例詳細說明： 第3圖為一系統方塊圖兑 像干擾之無線通訊系統的图基“中：二發？之抑制中頻假 地振盪器配合的情形。Κίίί硬太體:明織架構，並和本 像干擾之無線通訊系統1包含’、模广月f抑：中頻假 組12、RF前級低雜訊放大考模天^ f組11、第一濾波器模 14。 穴器板組13、以及第二濾波器模組 天線模組1 1負責接收V H F 45、古，a A i 夕/¾廨1垆僂迻$筮、舍頻率的無線訊號，並將所接收 之感，送至弟一慮波器模組12，以 第一濾波器模組1 2將對來白不綠y广^丁 /愿渡慝理 ^ ^ ^ ^ ^ ^ ^ ^ 12將訊號傳送給㈣、級低_放大器:组13以 進行放大作用。 放大3接/到經由第一濾波器模組12處理後之 訊號，ί/ I ?，、並將放大後的訊號傳送到第二滤 波器模組14，以進行訊號濾、波處理。 第二滤波器模組14接收到、經放大器'模組13處理完之訊 號後，將對訊號，行遽波處理，並將處理後之訊號傳送給後 續之混波器5以進行降頻處理。混波器5將配合本地振蘯器 6對由無線通訊糸統1而來之訊號做處理。可參考第8圖，於 160Mhz，230Mhz，300Mhz得--85dbm 以上。〃 ’ 在無線通訊系統1中，以調諧電路（tu°ned circuits)選 取所需的信號頻率。實際應用於電子高頻系統的調諧電 路’都是以並聯組成谐振電路，其組合線路型式有單調諧Page 7 519802 V. Description of the invention (5) ^^ Example detailed description: Figure 3 is a block diagram of a system block diagram of a wireless communication system that interferes with image interference. "Medium: Second round?" Κίίί The hard body: a woven structure that interferes with this image. The wireless communication system 1 contains', mode wide moon f: IF false group 12, RF pre-stage low noise amplification test mode ^ f group 11. The first filter mode 14. The cavity plate group 13, and the second filter module antenna module 1 1 are responsible for receiving VHF 45, ancient, a A i evening / ¾ 垆 偻 1 垆 偻 shift $ 筮, cut frequency Wireless signal, and send the received feelings to the first wave filter module 12, the first filter module 12 will be the opposite white and green. 丁丁 / 愿 渡 慝 理 ^ ^ ^ ^ ^ ^ ^ ^ 12 sends the signal to ㈣, stage low _ amplifier: group 13 for amplification. Amplify 3 is connected to the signal processed by the first filter module 12, ί / I?, And will be amplified. The subsequent signal is sent to the second filter module 14 for signal filtering and wave processing. After the second filter module 14 receives the signal processed by the amplifier 'module 13 The signal will be wave-processed, and the processed signal will be transmitted to the subsequent mixer 5 for frequency reduction processing. The mixer 5 will cooperate with the local oscillator 6 to come from the wireless communication system 1 The signal can be processed. Refer to Figure 8 for 160Mhz, 230Mhz, and 300Mhz to get more than --85dbm. 〃 'In wireless communication system 1, select the required signal frequency with tu ° ned circuits. Practical application Tuning circuits for electronic high-frequency systems are all composed of parallel resonant circuits, and the combined line type has single tuning
IH Εϋ» 第8頁 519802 五、發明說明（6) tuned)，雙調譜 — 、TriPle-tuned)。 二调諧 能元件ϊ ίϊ ί路一可為用二/固^，抗性元件，或是稱為儲 的選擇特性，以選取糸所统：：巧用的調諧電路，應'用其頻寬 號。 所需的信號頻率，同時排拒不需要的信 聯諧振電2以及^二遽波器模組1 4,可利用並 電路電路，來予以實施。以下將對此些 第4 m A 具有之特性予以說明。 如第^中二$圖、2中顯〒LC並聯諧振電路的電路架構。 容支路電容器的選擇，品質要求甚高，使得電 咸支败I的電值都很低，一般而言，可忽略不計；而在電 ^ 路中;如線圈的Q值甚高時，電阻值亦可忽略不計，因 反’許聯諧振（paral lel resonance)時的訊號頻率，或稱為 2 咱，頻率（anti—res〇nance frequency)fG，f。約為+ LC，所得之fG與串聯諧振頻率相同。電抗性元件的儲 t特性，是以品質因數Q值來說明其優劣。在分析諧振電路 =，電路負載q值為Ql，而就其定義而言，仍可視為一種說明 $路特性的品質因數，一般而言，Ql值高則頻寬狹窄，而Ql 、低則頻寬廣闊，亦即顯示電路對信號選擇特性的優劣，故 以電路Q值（circuit)稱之。IH Εϋ »Page 8 519802 V. Description of the invention (6) tuned), double-tuned spectrum — TriPle-tuned). Two tuning energy elements ϊ ί Road one can be used as a two / solid, resistive element, or a selection feature called storage, to select the traditional system: a clever tuning circuit should use its bandwidth number. The required signal frequency can be eliminated at the same time as the undesired telecommunication resonance circuit 2 and the two-wave filter module 14 can be implemented by using a parallel circuit. The characteristics of these 4 m A will be described below. As shown in Figure 2 in Figure 2 and Figure 2, the circuit architecture of the LC parallel resonant circuit is shown. The choice of capacitors in the capacitor branch has high quality requirements, so that the electrical value of the capacitor I is very low. Generally speaking, it can be ignored; in the circuit, if the Q value of the coil is very high, the resistance The value can also be ignored, because the frequency of the signal at the time of anti-resonance resonance (paral lel resonance), or the frequency (anti-response frequency) fG, f. Approximately + LC, the fG obtained is the same as the series resonance frequency. The storage characteristics of a reactive element are described by its quality factor Q value. In the analysis of resonant circuit =, the circuit load q value is Ql, but in terms of its definition, it can still be regarded as a quality factor that describes the characteristics of $ path. Generally speaking, a high Ql value narrows the bandwidth, while Ql and low frequency Wide, that is, the quality of the signal selection characteristics of the display circuit, so it is called the circuit Q value (circuit).
第9頁 519802 五、發明說明（7) 由調諧電路的設計參數得知，負載Q值1是決定電路頻 寬的主要參數，而負載Q值的高低，決定於信號源與負載的 阻抗大小。低值信號源或負載阻抗，會增加負載效應而降 低Q值，因而使頻寬擴大，影響調諧電路對頻率的選擇。在 調諧電路的設計實務上，常因相關的阻抗值過低，而無法配 合高Q值之窄頻寬的要求。有時即使能勉強的計算出諧振 電路所需的電感值，亦常由於不切實際而無法製作，改善此 一設計狀況的設計技術，就是應用阻抗轉換（i m p e d a n c e transformation),將相關的阻抗提高，而相對的來說，當然 亦可藉以降低阻抗。 第5圖為一電路圖，其中顯示電容抽頭阻抗轉換電路的電路 架構。常用的阻抗轉換設計技術，乃是將諧振電路中的電 感或電容，分成兩個串接部份，再將需要轉換為高值的低值 電阻，與其中之一並接，如第5圖中所示，可將電容C一分為 二，一為Ca而另一為Cb，而成為電容抽頭（tapped-C)的調諧 電路，常用於設計振盈電路，或是狹窄頻寬的南頻放大電 路。將原有二個元件組成的諧振電路，改以三個元件取代， 可為高頻電路的狹窄頻寬設計，提供較多的運用空間，此類 諧振電路的主要用途，是設計為高選擇性的窄頻寬電路，一 般而言，電路的負載Q值t - 10。 電容抽頭阻抗轉換電路，用以設計為高頻放大電路的 輸入級，以提升天線模組或是前級放大輸入端的低值阻 抗。 如第5圖中所示之電容抽頭（tapped-C)的調諧電路，當Page 9 519802 V. Description of the invention (7) According to the design parameters of the tuning circuit, the load Q value 1 is the main parameter that determines the circuit bandwidth, and the load Q value depends on the impedance of the signal source and load. A low-value signal source or load impedance will increase the load effect and lower the Q value, thus expanding the bandwidth and affecting the frequency selection of the tuning circuit. In the design practice of the tuning circuit, the relevant impedance value is often too low to meet the narrow bandwidth requirements of high Q values. Sometimes even if the inductance value required for a resonant circuit can be calculated barely, it is often impossible to make it due to impracticality. The design technique to improve this design situation is to apply impedance transformation to increase the relevant impedance. In contrast, of course, it can also reduce the impedance. Fig. 5 is a circuit diagram showing a circuit structure of a capacitor-tap impedance conversion circuit. The commonly used impedance conversion design technology is to divide the inductance or capacitance in the resonance circuit into two series parts, and then convert the high value low value resistance to one of them in parallel, as shown in Figure 5. As shown, the capacitor C can be divided into two, one is Ca and the other is Cb, and it becomes a capacitor tapped-C tuning circuit, which is often used to design a vibrating circuit, or a narrow bandwidth South frequency amplifier. Circuit. The original resonant circuit composed of two components is replaced by three components, which can be designed for the narrow bandwidth of high-frequency circuits and provide more application space. The main purpose of this resonant circuit is to design it with high selectivity. The narrow-bandwidth circuit, in general, the load Q of the circuit is t-10. The capacitor tapped impedance conversion circuit is designed as the input stage of the high-frequency amplifier circuit to improve the low impedance of the antenna module or the preamplifier input. The tuning circuit of the capacitor-tapped (C) shown in Figure 5, when
第10頁 519802 五、發明說明（8) 元件串聯令電抗為0(即短路），可求出通過頻率Wp，Wp=l + ，（LCa),亦即fp=l + 2 7Γ，（LCa);而元件並聯令導納為 0(即開路），可求出阻隔頻率Wb，Wb二/'[1/Lx (1/Ca + 1/Cb)]， 亦即，fb二（1/2 7Γ ) x /"[1/L x (1/Ca+1/Cb)]。Page 10 519802 V. Explanation of the invention (8) The element is connected in series to make the reactance 0 (short circuit), and the passing frequency Wp, Wp = l +, (LCa), that is, fp = l + 2 7Γ, (LCa) ; And the parallel connection of the components makes the admittance 0 (ie, open circuit), and can obtain the blocking frequency Wb, Wb two / '[1 / Lx (1 / Ca + 1 / Cb)], that is, fb two (1/2 7Γ ) x / " [1 / L x (1 / Ca + 1 / Cb)].
在高頻電路中，如果僅以單一的諧振電路，用為帶通濾 波者，在實際的應用上並不合適，主要的原因乃是由於其頻 率響應曲線，即使在帶通區内已夠狹窄，但是在進入截止區 時，通常稱為π裙邊π的兩側仍然不夠陡削。以致衰減不足， 而使選擇特性不盡理想，再者，如果要設計更窄的頻寬，必 須要提高負載Q值，相對的，必須要有高Q值的元件來配合， 不過，即使如此設計，仍不一定能使π裙邊π顯得更為陡削。 若再從另一面來看，如果希望設計低負載Q值的寬頻帶時， 通帶區的兩侧仍舊必須陡削，才能保持適當的選擇性。單 一的諧振電路，除了通帶區的兩侧不夠陡削外，且在通帶區 内的頻率響應曲線，頂端亦多不夠平坦。為了消除這些設 計上的缺點，我們採用耦合的調諧電路，可將數個單一的諧 振電路，在此，我們使用二個單一的諧振電路，而耦合成為 組調諧電路，而此耦合電路的頻率響應曲線，在通帶區的頂 部稍寬，同時可設計的較為平坦，而在進入截止區時，更有 陡削的’’裙邊’’，因而可以大幅提升調諧電路的選擇性。In high-frequency circuits, if only a single resonant circuit is used as a band-pass filter, it is not suitable for practical applications. The main reason is that its frequency response curve is narrow enough even in the band-pass region. However, when entering the cut-off area, the sides commonly called π skirt π are still not sharp enough. As a result, the attenuation is insufficient and the selection characteristics are unsatisfactory. Furthermore, if you want to design a narrower bandwidth, you must increase the load Q value. In contrast, you must have high Q components to cooperate. However, even if you design , Still does not necessarily make the π skirt π appear sharper. Looking at the other side, if you want to design a wide band with a low load Q value, both sides of the passband must still be sharpened to maintain proper selectivity. A single resonant circuit, in addition to the two sides of the passband region, is not sharp enough, and the frequency response curve in the passband region is not flat enough. In order to eliminate these design shortcomings, we use a coupled tuning circuit that can couple several single resonant circuits. Here, we use two single resonant circuits to couple into a group tuning circuit, and the frequency response of this coupling circuit The curve is slightly wider at the top of the passband area, and can be designed more flat at the same time. When entering the cutoff area, it has a sharper "skirt", which can greatly improve the selectivity of the tuning circuit.
第6圖為一電路圖，其中顯示雙調諧變壓器耦合電路的電路 架構。如圖中所示，在此，使用雙調譜變壓器耦合電路，以 變壓器耦合的調諧電路，亦為電感耦合電路的一種，此耦合 電路並非以電感直接連結，而是直接藉由二諧振電路的電Figure 6 is a circuit diagram showing the circuit architecture of a dual-tuned transformer coupling circuit. As shown in the figure, here, a dual-spectrum transformer coupling circuit is used, and a transformer-coupled tuning circuit is also a type of inductive coupling circuit. This coupling circuit is not directly connected by an inductor, but directly by a two-resonance circuit. Electricity
第11頁 519802 五、發明說明（9) 感中，所形成的磁力線互相耦合。電路中的Μ稱為互感 (mutual inductance),顯示二譜振電路為電感性耗合。在 電路中，Μ雖非任何元件之值，但對電路的功能表現，甚為重 要，Μ = Κ X / (Le X Lf) ， Le及1^分別為諧振電路Ε初線圈以 及諸振電路F次線圈的電感值，而K為耦合係數（coupling coefficient)。躺合係數K值，決定於電路E初線圈的磁力 線，與電路F次線圈實際連結之量，K值為介於0至1之間。 在應用時，一般都取臨界耦合，當為臨界耦合時，將在線路F 之次線圈Lf中，產生最大的電流，臨界耦合係數Ke，Kc=l 士 ，（Q1 X Q2)Page 11 519802 V. Description of the invention (9) In the sense, the magnetic lines of force formed are coupled to each other. The M in the circuit is called mutual inductance, showing that the two-spectrum oscillator circuit is inductive consumable. In the circuit, M is not the value of any component, but it is very important for the functional performance of the circuit. M = Κ X / (Le X Lf), Le and 1 ^ are the initial coil of the resonance circuit E and the vibration circuits F, respectively. The inductance of the secondary coil, and K is the coupling coefficient. The value of K is determined by the magnetic field lines of the primary coil of circuit E and the actual connection amount of the secondary coil of circuit F. The value of K is between 0 and 1. In application, the critical coupling is generally adopted. When the critical coupling is adopted, the maximum current will be generated in the secondary coil Lf of the line F, and the critical coupling coefficient Ke, Kc = l ±, (Q1 X Q2)
Q 1二電路E初線圈電路Q值 Q2=電路F次線圈電路Q值， 且Kc=l + QL，其中，為諧振時的電路Q值。Q 1 The Q value of the primary coil circuit of the second circuit E Q2 = The Q value of the F coil circuit of the circuit F, and Kc = l + QL, where is the circuit Q value at the time of resonance.
第7圖為一頻率響應圖，其中顯示不同之耦合係數的頻 率響應。當耦合係數增大時，調諧電路的總頻寬會隨之增 加。當k $ Ke時，次圈電流12的頻率響應曲線只有在諧振 頻率f〇時，有一峰值，且在k = K。時，振幅最大。當k>Kc時為 過度耦合，在頻率響應中會出現二個波峰，一個波谷。如第 7圖中所示，不同k值時，會有不同的頻率響應，以電壓增益 表出的頻率響應曲線，電壓增益與次圈電流12為成正比。 當耦合係數增大時，調諧電路的總頻寬會隨之增加。在增 大至臨界耦合時，頻寬將為最大，但尚未***成二個尖峰。 假設若再繼續增加k值，則高於臨界耦合值K。後，頻寬仍在 增加，惟將出現二個尖峰。Figure 7 is a frequency response diagram showing the frequency response of different coupling coefficients. As the coupling factor increases, the total bandwidth of the tuning circuit increases. When k $ Ke, the frequency response curve of the secondary current 12 has a peak only at the resonance frequency f0, and at k = K. When the amplitude is maximum. When k > Kc is over-coupling, two peaks and one trough appear in the frequency response. As shown in Figure 7, for different values of k, there will be different frequency responses. The frequency response curve is expressed by the voltage gain. The voltage gain is proportional to the secondary current 12. As the coupling coefficient increases, the total bandwidth of the tuning circuit increases. When increasing to critical coupling, the bandwidth will be maximum, but it has not split into two spikes. It is assumed that if the value of k is further increased, it is higher than the critical coupling value K. Later, the bandwidth is still increasing, but there will be two spikes.
第12頁 519802 五、發明說明（10) 第8圖為一系統方塊圖，其中顯示本發明之抑制中頻假 像干擾之無線通訊系統的第一濾波器模組的一實施例的電 路圖。如圖中所示，第一濾波器模組1 2為一雙調諧變壓器 耦合電路123，而此雙調諧變壓器耦合電路123含有轉換電 路121、以及轉換電路122。 雙調諧變壓器耦合電路1 2 3為以變壓器L 1、L 2耦合的調諧 電路，為電感耦合電路的一種，此耦合電路123並非以電感 直接連結，而是直接藉由轉換電路121、以及轉換電路122 的電感中，所形成的磁力線互相耦合。耦合電路123中的互 感M1，顯示轉換電路121、以及轉換電路122為電感性耦 合。 在耦合電路123中，Ml雖非任何元件之值，但對電路的 功能表現，甚為重要，M1=K X '(LI X L2)，Ll，L2分別為轉換 電路121初線圈、以及轉換電路122次線圈的電感值，而K為 耦合係數。耦合係數K值，決定於轉換電路1 2 1初線圈的磁 力線，與轉換電路1 2 2次線圈實際連結之量，可依實際需求 而選取所需之K值。 在應用時，一般都取臨界耦合，當為臨界耦合時，將在轉換 電路1 2 2之次線圈L2中，產生最大的電流，臨界耦合係數Kc， Kc=l 士/~(Q1 X Q2) Q 1 =轉換電路1 2 1初線圈電路Q值 Q2 =轉換電路122次線圈電路Q值， 且Kc=l + ，其中，為諧振時的電路Q值。 第9圖為一系統方塊圖，其中顯示本發明之抑制中頻假Page 12 519802 V. Description of the invention (10) Fig. 8 is a system block diagram showing a circuit diagram of an embodiment of the first filter module of the wireless communication system for suppressing IF artifact interference of the present invention. As shown in the figure, the first filter module 12 is a dual-tuned transformer coupling circuit 123, and the dual-tuned transformer coupling circuit 123 includes a conversion circuit 121 and a conversion circuit 122. The dual-tuned transformer coupling circuit 1 2 3 is a tuning circuit coupled by the transformers L 1 and L 2 and is a type of inductive coupling circuit. This coupling circuit 123 is not directly connected by an inductor but directly through the conversion circuit 121 and the conversion circuit. In the 122 inductance, the magnetic lines of force formed are coupled to each other. The mutual inductance M1 in the coupling circuit 123 shows that the conversion circuit 121 and the conversion circuit 122 are inductively coupled. In the coupling circuit 123, although M1 is not the value of any component, it is very important for the functional performance of the circuit. M1 = KX '(LI X L2), L1 and L2 are the primary coil of the conversion circuit 121 and the conversion circuit 122, respectively. The inductance of the secondary coil, and K is the coupling coefficient. The value of the coupling coefficient K is determined by the magnetic field lines of the primary coil of the converter circuit 121 and the actual connection of the secondary coil of the converter circuit 12 and 2. The required K value can be selected according to actual needs. In the application, the critical coupling is generally adopted. When the critical coupling is adopted, the maximum current will be generated in the secondary coil L2 of the conversion circuit 1 2, and the critical coupling coefficient Kc, Kc = l person / ~ (Q1 X Q2) Q 1 = conversion circuit 1 2 1 Q value of the primary coil circuit Q2 = 122 time of the coil circuit of the conversion circuit, and Kc = 1 +, where is the circuit Q value at resonance. Figure 9 is a system block diagram showing the suppression of intermediate frequency glitches of the present invention.
519802 五、發明說明（11) 像干擾之無線通訊系統的第二濾波器模組的一實施例的電 路圖。如圖中所示，第二濾波器模組14為一雙調諧變壓器 麵合電路143，而此雙調諧變壓器輕合電路143含有轉換電 路“以及轉換電謹。雙調譜變壓；耗合3電有路= 以變壓器L3、L4耦合的調諧電路，為電感耦合電路的一種 此1合電路U3並非以電感直接連結，而是直接藉由電 ，=i、以及轉換電路丨4 2的電感中所形成的磁力線互/ 耦合。耦合電路丨43中的互感M2,顯示轉換電路141、 轉換電路142為電感性耦合。 Λ及 在耦合電路1 43中，M2雖非任何元件之值，但 功能表現，甚為重要，M2=Kx ^(L3x 換電路141初線圈、以及轉換電路142次線圈的電 為轉 為，=係數。耦合係數κ值，決定於轉換電路14〜圈而K 磁力線，與轉換電路142次線圈實際連結之量，可依的 求而選取所需之K值。 貝降需 在應用時，一般都取臨界耦合，當為臨界耦 電路142之次線圈14中，產生最大耦人换 ，K，1+，(Q3x Q4) ^ ^ 界耦合係敖、 Q3= LC並聯諧振電路141初線圈電路Q值 Q4 = LC並聯諧振電路142次線圈電路Q值， 且Kc - 1 · ql，其中，ql為譜振時的電路卩值。 J 10 :為帶通濾波振幅頻率響應圖，用以顯示本發 Ξ H像干擾之無線通訊系統的帶通渡波器頻譜圖p 圖中所不，預期接收頻率為30 0MHZ，且無如習知之假知 519802 五、發明說明（12) 頻率，由頻譜展示可知接收頻率以及雜訊之db差值為 -8 3 · 3 7 d b，由此可知，本發明之抑制中頻假像干擾之無線通 訊系統之頻譜，並無中頻假像干擾之情形，可有效地抑制頻 率假象干擾問題，並具有較佳之頻率響應，而為一般習知系 統所無法達到的。519802 V. Description of the invention (11) Circuit diagram of an embodiment of the second filter module of an interference-free wireless communication system. As shown in the figure, the second filter module 14 is a double-tuned transformer surface-bonding circuit 143, and this double-tuned transformer light-on circuit 143 contains a conversion circuit and a conversion circuit. Electrical circuit = Tuning circuit coupled by transformers L3 and L4, which is a type of inductive coupling circuit. This 1-in circuit U3 is not directly connected by inductance, but directly by electricity, = i, and the conversion circuit. The magnetic field lines formed are mutual / coupled. The mutual inductance M2 in the coupling circuit 丨 43 shows that the conversion circuit 141 and the conversion circuit 142 are inductive coupling. Λ and in the coupling circuit 1 43, although M2 is not the value of any component, it has a functional performance It is very important that M2 = Kx ^ (L3x The electric power of the 141 primary coil of the circuit and the 142 secondary coil of the conversion circuit is converted to = coefficient. The value of the coupling coefficient κ is determined by the conversion circuit 14 ~ circles and the K magnetic field lines and conversion The amount of actual connection of the 142 secondary coils of the circuit can be selected according to the required value of K. In the application, the critical coupling is generally used. When the secondary coil 14 of the critical coupling circuit 142 is used, the maximum coupling is generated. Change, K, 1+, (Q3x Q4) ^ ^ Boundary coupling system, Q3 = LC parallel resonance circuit 141 primary coil circuit Q value Q4 = LC parallel resonance circuit 142th coil circuit Q value, and Kc-1 · ql, where ql is the circuit threshold value during spectral vibration. J 10 is the amplitude-frequency response diagram of the band-pass filter, which is used to display the spectrum diagram of the band-pass ferrule of the wireless communication system of this image. The expected reception frequency is 300 MHz, and it is not as known. Hypothesis 519802 V. Description of the invention (12) The frequency shows that the difference between the received frequency and the db difference of noise is -8 3 · 3 7 db. From this, it can be seen that the wireless communication of the present invention suppresses intermediate frequency artifact interference. The frequency spectrum of the system does not have the situation of intermediate frequency artifacts, which can effectively suppress the problem of frequency artifacts, and has a better frequency response, which cannot be achieved by conventional systems.
第1 1圖為實體電路圖，用以顯示本發明之抑制中頻假像干 擾之無線通訊系統的帶通濾波器之一實施例，於印刷電路 板上實施的實際排列方式。圖中所示，白色區域為帶通濾 波Is的導電線路之印刷電路銅络線路，而黑色區域則為到 除銅箔區，此黑色區域上未附著印刷電路銅箔，且並非為導 電線路。亦即，由圖中可知，除了帶通濾波器的導電線路之 印刷電路銅箔線路外，尚刮除了其餘未參與導電線路之印 刷電路銅箔（圖中之黑色區域部份），以增加帶通濾波器之 電路Q值以及頻率響應。FIG. 11 is a physical circuit diagram showing an actual arrangement of a band-pass filter of a wireless communication system for suppressing IF artifact interference of the present invention, implemented on a printed circuit board. As shown in the figure, the white area is the printed circuit copper wire of the conductive circuit with the band-pass filter Is, and the black area is the copper foil removal area. The printed circuit copper foil is not attached to this black area and is not a conductive line. That is, it can be seen from the figure that in addition to the printed circuit copper foil circuit of the conductive circuit of the band-pass filter, the remaining printed circuit copper foil (the black area in the figure) that does not participate in the conductive circuit is scraped to increase the band Circuit Q value and frequency response of the pass filter.
第1 2圖為實體電路圖，用以顯示本發明之抑制中頻假像干 擾之無線通訊系統的帶通濾波器之另一實施例，於印刷電 路板上實施的實際排列方式。圖中所示，白色區域為帶通 滤波器的導電線路之印刷電路銅猪線路，而黑色區域則為 刮除銅箔區，此黑色區域上未附著印刷電路銅箔，且並非為 導電線路。亦即，由圖中可知，除了帶通濾波器的導電線路 之印刷電路銅箔線路外，尚刮除了其餘未參與導電線路之 印刷電路銅箔（圖中之黑色區域部份），以增加帶通濾波器 之電路Q值以及頻率響應。 綜合以上的實施例以及方法，我們可以得到本發明之一種Fig. 12 is a physical circuit diagram showing the actual arrangement of the band-pass filter of the wireless communication system for suppressing IF artifact interference according to another embodiment of the present invention implemented on a printed circuit board. As shown in the figure, the white area is the printed circuit copper pig circuit of the conductive circuit of the band-pass filter, and the black area is the scraped copper foil area. The printed circuit copper foil is not attached to the black area and is not a conductive circuit. That is, it can be seen from the figure that in addition to the printed circuit copper foil circuit of the conductive circuit of the band-pass filter, the remaining printed circuit copper foil (the black area in the figure) that does not participate in the conductive circuit is scraped to increase the band. Circuit Q value and frequency response of the pass filter. Combining the above embodiments and methods, we can obtain one of the present invention
第15頁 519802 2、發明說明（13) 抑制中頻假像干擾之無線通訊系統，在V H F頻段 1 6 0 M h ζ〜3 0 0 M h ζ % 土兄中，於操作時可有效地抑制中頻假像干 擾，並提高所需頻寬之正增益dbm功率值，使得天線所接收 之感應訊號經由濾波器而到放大器時，其選擇頻寬能變窄， 使得於同樣之正dbm值的環境下，預計接收頻率之頻寬變 窄，使具有較佳之選擇性頻率響應，而能有效地避免中頻假 象干擾問題。本發明之抑制中頻假像干擾之無線通訊系統 包含天線模組、第一濾波器模組、前級低雜訊放大器模 組、以及第二濾波器模組。天線模組負責接收V H F頻率的 無線訊號，並將所接收之感應訊號傳送至第一濾波器模組， 以進行遽波處理。第一濾波器模組將對來自天線模組之感 應訊號做渡波處理，以將不必要的雜訊予以濾掉。在無線 訊號巧收系統中，以調諧電路選取所需的信號頻率。第一 滤波器模組將處理後之訊號傳送給放大器模組，以進行放 大作用。放大器模組接收到經由第一濾波器模組處理後之 3 Ϊ 將訊號3以放大，並將放大後的訊號傳送到第二遽 接二二ί，^\進5第二次訊號滤波處理。第二濾波器模組 ▲啸、、古ί採 器模組處理完之訊號後，將對訊號進行第二 耔卢搜女欢〇將處理後之訊號傳送給後續之混波器，以進 >ί 丁處理。本發明夕 & , 的優點有· 一種抑制中頻假像干擾之無線通訊系統 1 ·提供一種抑制中相 環境中，於操作時π 士假像干擾之無線通訊系統，應用於VHF 2·應用於VHF環埼Z有效地抑制中頻假像干擾。 τ，可提高所需選擇頻寬之+ dbm功率值，Page 15 519802 2. Description of the invention (13) Wireless communication system for suppressing IF artifact interference in the VHF band 160 Mh ζ ~ 3 0 0 M h ζ% In Tutu, it can be effectively suppressed during operation Intermediate frequency artifact interference, and increase the positive gain dbm power value of the required bandwidth, so that when the induction signal received by the antenna passes the filter to the amplifier, its selection bandwidth can be narrowed, so that the same Under the environment, the bandwidth of the receiving frequency is expected to be narrowed, so that it has a better selective frequency response, and can effectively avoid the problem of intermediate frequency artifacts. The wireless communication system for suppressing intermediate frequency artifacts of the present invention includes an antenna module, a first filter module, a pre-stage low noise amplifier module, and a second filter module. The antenna module is responsible for receiving wireless signals of V H F frequency, and transmitting the received induction signals to the first filter module for wave processing. The first filter module will process the inductive signal from the antenna module to filter out unnecessary noise. In a wireless signal receiving system, the required signal frequency is selected by a tuning circuit. The first filter module sends the processed signal to the amplifier module for amplification. The amplifier module receives the signal processed by the first filter module. 3 放大 Amplifies the signal 3 and sends the amplified signal to the second 接. Then, the second signal filtering process is performed. After the second filter module ▲ Xiao, and the ancient miner module have processed the signal, they will perform a second signal search. Send the processed signal to the subsequent mixer to enter the> ; ί Ding processing. The advantages of the present invention are: · A wireless communication system for suppressing intermediate frequency artifacts. 1 · Provides a wireless communication system for suppressing π ± artifact interference during operation in a medium-phase environment, applied to VHF 2 · Applications The VHF loop 埼 Z effectively suppresses IF artifacts. τ, which can increase the required bandwidth + dbm power value,
第16頁 519802 五、發明說明（14) 使得天線所接收之感應訊號經由濾波器而到放大器時，其 選擇頻寬能變窄，使得於同樣之dbm值的環境下，能期望接 收頻率之頻寬變窄，具有較佳之頻率響應頻譜和選擇性，而 能有效地避免中頻假象干擾問題。 以上所述僅為本發明之較佳實施例而已，並非用以限 定本發明之範圍；凡其它未脫離本發明所揭示之精神下所 完成之等效改變或修飾，均應包含在下述之專利範圍内。Page 16 519802 V. Description of the invention (14) When the inductive signal received by the antenna reaches the amplifier through the filter, its selection bandwidth can be narrowed, so that the frequency of the receiving frequency can be expected under the same dbm value environment The width becomes narrower, which has better frequency response spectrum and selectivity, and can effectively avoid the problem of intermediate frequency artifacts. The above are merely preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Any equivalent changes or modifications made without departing from the spirit disclosed by the present invention shall be included in the following patents Within range.
第17頁 519802 圖式簡單說明 第1圖為一系統方塊圖，其中顯示習知的VHF接收系統的基 本系統硬體組織架構； 第2圖為帶通濾波振幅頻率響應圖，用以顯示如第1圖中之 接收系統的帶通濾波器頻譜圖； 第3圖為一系統方塊圖，其中顯示本發明之抑制中頻假像干 擾之無線通訊系統的基本系統硬體組織架構，並和本地振 盪器配合的情形； 第4圖為一電路圖，其中顯示LC並聯諧振電路的電路架構； 第5圖為一電路圖，其中顯示電容抽頭阻抗轉換電路的電路 架構； 第6圖為一電路圖，其中顯示雙調諧變壓器耦合電路的電路 架構； 第7圖為一頻譜分析圖，其中顯示不同之耦合係數的頻譜分 析； 第8圖為一系統方塊圖，其中顯示本發明之抑制中頻假像干 擾之無線通訊系統的第一濾波器模組的一實施例的電路 圖； 第9圖為一系統方塊圖，其中顯示本發明之抑制中頻假像干 擾之無線通訊系統的第二濾波器模組的一實施例的電路 圖； 第1 0圖為帶通濾波振幅頻率響應圖，用以顯示本發明之抑 制中頻假像干擾之無線通訊系統的帶通濾波器頻譜圖； 第1 1圖為實體電路圖，用以顯示本發明之抑制中頻假像干 擾之無線通訊系統的帶通濾波器之一實施例，於印刷電路Page 519802 Brief description of the diagram. The first diagram is a system block diagram showing the basic system hardware structure of a conventional VHF receiving system. The second diagram is the amplitude-frequency response diagram of the bandpass filter. Bandpass filter spectrum diagram of the receiving system in Figure 1; Figure 3 is a system block diagram showing the basic system hardware organization structure of the wireless communication system for suppressing IF artifact interference according to the present invention, and local oscillation Figure 4 is a circuit diagram showing the circuit architecture of an LC parallel resonant circuit. Figure 5 is a circuit diagram showing the circuit architecture of a capacitor tapped impedance conversion circuit. Figure 6 is a circuit diagram showing a dual The circuit architecture of the coupling circuit of the tuning transformer; FIG. 7 is a spectrum analysis diagram showing the spectrum analysis of different coupling coefficients; FIG. 8 is a system block diagram showing the wireless communication of the present invention for suppressing IF artifact interference A circuit diagram of an embodiment of the first filter module of the system; FIG. 9 is a system block diagram showing the suppression of intermediate frequency artifacts of the present invention A circuit diagram of an embodiment of a second filter module of an interfering wireless communication system; FIG. 10 is an amplitude-frequency response diagram of a band-pass filter, which is used to show the band of the wireless communication system for suppressing IF artifact interference of the present invention. Spectrum diagram of the pass filter; Figure 11 is a physical circuit diagram showing an embodiment of the band-pass filter of the wireless communication system for suppressing intermediate frequency artifacts according to the present invention.
第18頁 519802Page 519 802
第19頁Page 19
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| TW90125147A TW519802B (en) | 2001-10-12 | 2001-10-12 | Radio communication system for depressing mid-band false image interference |
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| TWI511428B (en) * | 2013-08-16 | 2015-12-01 | Delta Electronics Shanghai Co | Power converter and method for stabling the voltage gain |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| TWI511428B (en) * | 2013-08-16 | 2015-12-01 | Delta Electronics Shanghai Co | Power converter and method for stabling the voltage gain |
| US9343975B2 (en) | 2013-08-16 | 2016-05-17 | Delta Electronics (Shanghai) Co., Ltd. | Power converter and method of stabling voltage gain |
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