電聲式頻率計 的英文怎麼說
中文拼音 [diànshēngshìbīnlǜjì]
電聲式頻率計
英文
electroacoustic frequency meter- 電 : Ⅰ名詞1 (有電荷存在和電荷變化的現象) electricity 2 (電報) telegram; cable Ⅱ動詞1 (觸電) give...
- 式 : 名詞1 (樣式) type; style 2 (格式) pattern; form 3 (儀式; 典禮) ceremony; ritual 4 (自然科...
- 頻 : Ⅰ形容詞(次數多) frequent Ⅱ副詞(屢次) frequently; repeatedly Ⅲ名詞1 [物理學] (物體每秒鐘振動...
- 率 : 率名詞(比值) rate; ratio; proportion
- 計 : Ⅰ動詞1 (計算) count; compute; calculate; number 2 (設想; 打算) plan; plot Ⅱ名詞1 (測量或計算...
- 頻率 : frequency; rate
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In digital relay, the percentage of noise will increase rapidly with the increase of sampling rate when derivation calculus is substituted by sampled difference term. to solve this problem, a new method using fragment function integrated with the least square algorithm is proposed in this paper. the influence of white noise is greatly reduced and the accuracy of the dead angle calculation is nicely improved after adopting the new method
在數字式保護中,如果用差分代替求導將導致噪聲的百分比誤差隨著采樣頻率的提高而劇增,本文對此進行了分析並提出了用分段樣條函數最小二乘法來計算電流波形的導數值,以便在提高采樣率的同時降低噪聲誤差的影響,並將其應用於基於32位浮點dsp的新型變壓器保護裝置。This article takes hanging off and wide fluctuation of transmition velocity of adsl as example, then analysis centers on the discerte multiple tone and the principle of channel load assignation. from analysis above article points out the root of adsl being sensible of noise signal. at last, reserches effects that window function and barrier effect on frequency and adopts fft to work out the noise power of adsl
本文以電信現在推出的adsl傳輸中鏈路經常掉線和傳輸速率經常大范圍波動為例,重點分析了adsl所使用的dmt調制方式和注水演算法分配通道載荷方式原理,由此指出adsl對噪聲信號敏感的根源,在得到問題的根源之後,分析了窗函數和柵欄效應對頻譜的影響,採用fft方法計算adsl線路的噪聲功率譜,為adsl線路測試提供了可靠的理論依據。Then according to the emphasis of the design, went deeply into the theory of pll frequency synthesizers widely used, described pll ’ s working principle, structure and several types in detail, and made research and analysis of pll frequency synthesizers ’ phase noise, including the effect of the active loop filter on the phase noise, and give some methods to make improvement as well, such as changing loop filter form, reducing divide number, and increase phase detector frequency, etc. then paper introduced the principle character and phase noise analysis of direct digital frequency synthesizer ( dds ) and injection phase lock circuit, which are also important circuits in the design
論文首先對幾十年頻率合成器的發展進行概述,而後針對本次設計的重點,對應用較為廣泛的鎖相頻率合成理論進行了深入的探討,詳細介紹了鎖相環的工作原理、組成結構和鎖相類型,並對鎖相頻率合成器的相噪特性進行了研究分析,包括有源環路濾波器對于相噪的影響,提出了改善相位噪聲的幾點措施:改善環路形式、降低分頻數、增大鑒相頻率等。接著介紹了直接數字頻率合成器( dds )和注入鎖相電路的原理特點以及相噪分析,它們也是本次設計的重要電路。Transmit / receive ( t / r ) modules is the base of the modern radar. the paper puts forth a design scheme according to the target including t / r switch, up conversion, power amplified, low noise receive and down conversion. the dimension is restricted to 106 89mm through scheme comparison and the existing experiment condition, the final products arrive at the target we expect with millimeter hybrid integrated circuit
收發t / r組件在當今雷達系統中佔有舉足輕重的地位,本文根據設計指標提出了毫米波前端的設計方案,系統功能上要求完成收發雙工、上變頻和功率放大、低噪聲放大和下變頻功能,外形尺寸為106 89mm ,通過綜合方案比較,結合自身條件,選取了毫米波混合集成電路形式。Technology of fine processing was firstly used to make the lsaw biosensor with dual delay linear style. then we developed the dual channels resonance circuit and used the labview software to record and analyze phase / frequency automatically. so the detection system of lsaw biosensor was constructed by combing all these components with network analyzer and computer
方法: 1 .利用精細微加工方法制備雙延遲線型漏聲表面波傳感器,並自行開發研製自激式振蕩電路, labview相位、頻率記錄分析軟體,將它們與網路分析儀、頻譜分析儀及計算機聯用以構建lsaw生物傳感器檢測系統。On basic of researching the principle of phase locked loop, this article analyzes the output signal whose noise characteristics depend on the each part of pll, and designs a scheme to realize the frequency synthesizers using the high performance chips with integrated prescalers and phase detectors. the visualized circuit structure is given in this paper
本文在研究鎖相環路基本原理的基礎上,分析了鎖相式頻率合成器電路中各部件對環路輸出信號噪聲性能的影響,設計了以一個高性能的集成鎖相環頻率合成器晶元為基礎實現頻率合成的方案,並給出了具體的電路形式。分享友人