【正文】 也可以作為受聘于在無線通信系統(tǒng)的通用放大器頻率不同的條帶，測試設(shè)備，軍事電子戰(zhàn)系統(tǒng)。此外，50終止不需要在輸入和輸出寬帶匹配網(wǎng)絡(luò)，因此，一個 3 dB 的損失是可以避免的。因此，放大器只需要 13 倍的 fT 放大器的帶寬，以實現(xiàn)高帶寬。 50 歐姆終端目前雇用的輸入和輸出的寬帶放大器，以獲得理想的輸入和輸出寬帶匹配阻抗（低的 S11 和 S22）。這導(dǎo)致高成本，低產(chǎn)量的影響。速調(diào)管是可調(diào)的，提供其指定的頻率范圍內(nèi)選擇輸出。 微波放大器 行波管（ TWT）放大器 主條目：行波管 用于低頻率高功率微波放大。這種類型的放大器是常用的，因為最后的垂直放大器示波器。對階躍響應(yīng)，上升時間，過沖和畸變的規(guī)格可以使這些放大器的設(shè)計非常困難。 視頻放大器 這些處理視頻信號，并根據(jù)不同的帶寬是否為標(biāo)清視頻信號， EDTV， HDTV 的 720p或 1080i / p等的。每個配置有不同的特性（增益，阻抗 ...) （運算放 大器運算放大器） 主要文章：運算放大器和儀表放大器 運算放大器是一種具有很高的開環(huán)增益和差分輸入的員工為它的傳遞函數(shù)或外部反饋放大器增益控制電路。量的放大（以下簡稱 “ 遠(yuǎn)期收益 ” ）是由外部電路設(shè)計以及有源器件。效率的考慮導(dǎo)致各類功率放大器：見功率放大器類。關(guān)鍵組件包括例如真空管或晶體管有源器件。 穩(wěn)定是在射頻和微波放大器的主要問題。鈴聲響過沖的結(jié)果是由一個欠阻尼電路引起的。 上升時間 上升時間，章一個放大器，是為輸出所需的時間從 10％調(diào)整到 90 級時的最后一個步驟輸入驅(qū)動％。這 兩個比例是引述放大器的動態(tài)范圍。對于噪聲的電路的性能指標(biāo)是噪聲的數(shù)字或噪音的因素。 對非線性問題是最經(jīng)常與負(fù)反饋解決。 當(dāng)信號驅(qū)動放大器的增加，產(chǎn)量也增加，直到達(dá)到一個點，有部分放大器的部分變得飽和，不能產(chǎn)生任何更多的產(chǎn)出，這就是所謂的剪報，以及扭曲的結(jié)果。 在射頻功率放大器，如蜂窩基站和廣播發(fā)射機(jī)，專門設(shè)計技術(shù)被用來提高效率。 CF卡類放大器通常被稱為是非常高中北大學(xué) 2021 屆畢業(yè)設(shè)計說明書 第 11 頁 共 15 頁 效率的放 大器。 B 類放大器具有很高的效率，而且是因為高層次的失真（見：交叉失真音頻工作不切實際）。現(xiàn)代開關(guān)放大器必須在陡峭的低通 濾波的輸出獲得的高開關(guān)頻率的噪聲和諧波消除。 一個良好的質(zhì)量贏得全音域音頻放大器將基本持平， 20 赫茲至 20 千赫（正常人類的聽覺范圍）。然而，共同的和普遍接受的衡量標(biāo)準(zhǔn)是半功率點（即在斷電的頻率降低一半的峰值）在輸出與頻率的曲線。 however, they are usually not as tunable as klystrons. Klystrons Main article: Klystron Very similar to TWT amplifiers, but more powerful and with a specific frequency sweet spot. They generally are also much heavier than TWT amplifiers, and are therefore illsuited for lightweight mobile applications. Klystrons are tunable, offering selective output within their specified frequency range. Musical instrument (audio) amplifiers Main articles: Instrument amplifier and Audio amplifier An audio amplifier is usually used to amplify signals such as music or speech Background: Without a distributed amplifier, most broadband amplifier bandwidths can be achieved around 1/10 to 1/3 of their fT only. Therefore, a high bandwidth amplifier 中北大學(xué) 2021 屆畢業(yè)設(shè)計說明書 第 8 頁 共 15 頁 requires high fT (at least 310 times of the amplifier bandwidth) transistors in order to achieve high bandwidth. Unfortunately, the current device technology is limited and in very high fT transistors, yield is still low. This leads to high cost and low yield. Even if high gainbandwidth product could be achieved by a distributed amplifier, the major disadvantages of the distributed amplifier are large area, and high dc power consumption. Transistors were operated with high current density for high fT in order to achieve high bandwidth amplification. However, the transistors would bee highly stressed resulting in reliability problems and short lifetimes. 50 ohm terminations are currently employed at the input and output of broadband amplifiers in order to obtain desirable input and output broadband impedance matches (low S11 and S22). However, the disadvantage is 3dB losses at theirs inputs and outputs. Technology: University researchers have developed a design method by bining threestage amplifier design to achieve a broadband amplifier with desirable gain, large bandwidth, low power consumption, low input/output reflection coefficients, low loss, and good reliability. Without a distributed amplifier, the invented broadband amplifier bandwidth of 1/2 of fT and/or approaching to fT can be achieved. Therefore, the amplifiers requires only fT of 13 times of the amplifier bandwidth in order to achieve high bandwidth. The broadband amplifier area and dc power consumption will be small and low respectively. With the invented broadband amplifier, transistors are operated with typical current density, but high amplifier bandwidth can still be achieved. Therefore, the transistors are not stressed at high current density, thus leading to better reliability and long lifecycles. Also, 50 termination is not required in the input and output broadband matching work, therefore, a 3dB loss is avoidable. S11 can be kept low over the operating bandwidth even with DC supply varied from 0 to , and S22 is low over the operating bandwidth as well. This advantage is very useful for broadband amplifiers, and they can be easily cascaded as well. Application: The invented broadband amplifier can be applied in fiberoptic munications as a modulator driver, limiting, automatic gain control and as transimpedance amplifiers. It can also be employed in various bands of frequencies as generalpurpose amplifiers in 中北大學(xué) 2021 屆畢業(yè)設(shè)計說明書 第 9 頁 共 15 頁 wireless munication systems, in testing equipments, and in military electronics warfare systems. The quality of an amplifier can be char