[p]=ss_Pe42(rho_in_dB) ％ SS_PE42 finds the measured error rate for the given value of ％ signal per interference ratio in dB.
標(biāo)簽： rho_in_dB the measured signal
上傳時間： 2014-01-13
上傳用戶：qw12
Shortest Paths with Multiplicative Cost. In a given undirected graph, the path cost is measured as a product of all the edges in the path. The weights are rational numbers (e.g., 0.25, 0.75, 3.75 etc) or integers (2, 3). There are no negative edges. Given such a graph as input, you are to output the shortest path between any two given vertices. Input is the adjacency matrix and the two vertices. You must output the path.
標(biāo)簽： Multiplicative undirected Shortest measured
上傳時間： 2017-04-08
上傳用戶：邶刖
This is Temperature PID regulator for Tamman ovens. Temperature is measured by thermocouple via lm358 - > Atmega s ADC and regulated over triac. All data is sent via RS232 connection on PC and controlled by LabView.
標(biāo)簽： Temperature thermocouple regulator measured
上傳時間： 2017-07-04
上傳用戶：zhouli
微弱信號檢測裝置 四川理工學(xué)院 劉鵬飛、梁天德、曾學(xué)明 摘要： 本設(shè)計(jì)以TI的Launch Pad為核心板，采用鎖相放大技術(shù)設(shè)計(jì)并制作了一套微弱信號檢測裝置，用以檢測在強(qiáng)噪聲背景下已知頻率微弱正弦波信號的幅度值，并在液晶屏上數(shù)字顯示出所測信號相應(yīng)的幅度值。實(shí)驗(yàn)結(jié)果顯示其抗干擾能力強(qiáng)，測量精度高。 關(guān)鍵詞：強(qiáng)噪聲；微弱信號；鎖相放大；Launch Pad Abstract: This design is based on the Launch Pad of TI core board, using a lock-in amplifier technique designed and produced a weak signal detection device, to measure the known frequency sine wave signal amplitude values of the weak in the high noise background, and shows the measured signal amplitude of the corresponding value in the liquid crystal screen. Test results showed that it has high accuracy and strong anti-jamming capability. Keywords: weak signal detection; lock-in-amplifier; Launch Pad 1、引言 隨著現(xiàn)代科學(xué)技術(shù)的發(fā)展，在科研與生產(chǎn)過程中人們越來越需要從復(fù)雜高強(qiáng)度的噪聲中檢測出有用的微弱信號，因此對微弱信號的檢測成為當(dāng)前科研的熱點(diǎn)。微弱信號并不意味著信號幅度小，而是指被噪聲淹沒的信號，“微弱”也僅是相對于噪聲而言的。只有在有效抑制噪聲的條件下有選擇的放大微弱信號的幅度，才能提取出有用信號。微弱信號檢測技術(shù)的應(yīng)用相當(dāng)廣泛，在生物醫(yī)學(xué)、光學(xué)、電學(xué)、材料科學(xué)等相關(guān)領(lǐng)域顯得愈發(fā)重要。 2、方案論證 針對微弱信號的檢測的方法有很多，比如濾波法、取樣積分器、鎖相放大器等。下面就針對這幾種方法做一簡要說明。 方案一：濾波法。 在大部分的檢測儀器中都要用到濾波方法對模擬信號進(jìn)行一定的處理，例如隔離直流分量，改善信號波形，防止離散化時的波形混疊，克服噪聲的不利影響，提高信噪比等。常用的噪聲濾波器有：帶通、帶阻、高通、低通等。但是濾波方法檢測信號不能用于信號頻譜與噪聲頻譜重疊的情況，有其局限性。雖然可以對濾波器的通頻帶進(jìn)行調(diào)節(jié)，但其噪聲抑制能力有限，同時其準(zhǔn)確性與穩(wěn)定性將大打折扣。
標(biāo)簽： 2012 TI 電子設(shè)計(jì)大賽 微弱信號
上傳時間： 2013-11-04
上傳用戶：lty6899826
Abstract: The DS4830 optical microcontroller's analog-to-digital converter (ADC) offset can change with temperature and gainselection. However, the DS4830 allows users to measure the ADC internal offset. The measured ADC offset is added to the ADCoffset register to nullify the offset error. This application note demonstrates the DS4830's ADC internal offset calibration in theapplication program.
標(biāo)簽： 4830 ADC DS 校準(zhǔn)
上傳時間： 2014-12-23
上傳用戶：萍水相逢
Control systems are becoming increasingly dependent on digital processing and so require sensors able to provide direct digital inputs. Sensors based on time measurement, having outputs based on a frequency or phase, have an advantage over conventional analogue sensors in that their outputs can be measured directly in digital systems by pulse counting.
上傳時間： 2013-10-08
上傳用戶：wuyuying
Calculation of the Differential Impedance of Tracks on FR4 substrates There is a discrepancy between calculated and measured values of impedance for differential transmission lineson FR4. This is especially noticeable in the case of surface microstrip configurations. The anomaly is shown tobe due to the nature of the substrate material. This needs to be considered as a layered structure of epoxy resinand glass fibre. Calculations, using Boundary Element field methods, show that the distribution of the electricfield within this layered structure determines the apparent dielectric constant and therefore affects theimpedance. Thus FR4 cannot be considered to be uniform dielectric when calculating differential impedance.
上傳時間： 2014-12-24
上傳用戶：DE2542
鎖定放大是微弱信號檢測的重要手段。基于相關(guān)檢測理論，利用開關(guān)電容的開關(guān)實(shí)現(xiàn)鎖定放大器中乘法器的功能，提出開關(guān)電容和積分器相結(jié)合以實(shí)現(xiàn)相關(guān)檢測的方法，并設(shè)計(jì)出一種鎖定放大器。該鎖定放大器將微弱信號轉(zhuǎn)化為與之相關(guān)的方波，通過后續(xù)電路得到正比于被測信號的直流電平，為后續(xù)采集處理提供方便。測量數(shù)據(jù)表明鎖定放大器前級可將10-6 A的電流轉(zhuǎn)換為10-1 V的電壓，后級通過帶通濾波器級聯(lián)可將信號放大1×105倍。該方法在降低噪聲的同時，可對微弱信號進(jìn)行放大，線性度較高、穩(wěn)定性較好。 Abstract: Lock-in Amplifying（LIA）is one of important means for weak signal detection. Based on cross-correlation detection theory， switch in the swithched capacitor was used as multiplier of LIA， and a new method of correlation detection was proposed combining swithched capacitor with integrator. A kind of LIA was designed which can convert the weak signal to square-wave， then DC proportional to measured signal was obtained through follow-up conditioning circuit， providing convenience for signal acquisition and processing. The measured data shows that the electric current（10-6 A） can be changed into voltage（10-1 V） by LIA， and the signal is magnified 1×105 times by cascade band-pass filter. The noise is suppressed and the weak signal is amplified. It has the advantages of good linearity and stability.
標(biāo)簽： 開關(guān)電容 鎖定放大器
上傳時間： 2013-11-29
上傳用戶：黑漆漆
為提高電容測量精度，針對電容式傳感器的工作原理設(shè)計(jì)了基于PIC16LF874單片機(jī)電容測量模塊。簡單闡述了電容測量電路的應(yīng)用背景和國內(nèi)外研究現(xiàn)狀，介紹了美國Microchip公司PIC16LF874單片機(jī)的特性。電容式傳感器輸出的動態(tài)微弱電容信號通過PS021型電容數(shù)字轉(zhuǎn)換器把模擬量數(shù)據(jù)轉(zhuǎn)換成數(shù)字量數(shù)據(jù)，所測數(shù)據(jù)由PIC16LF874單片機(jī)應(yīng)用程序進(jìn)行處理、顯示和保存。實(shí)驗(yàn)結(jié)果表明，固定電容標(biāo)稱值為10~20 pF 的測量值相對誤差在1%以內(nèi)，同時也可知被測電容容值越大，測量值和標(biāo)稱值相對誤差越小。 Abstract: To improve the accuracy of capacitance measurement，aimed at the principle of work of mercury capacitance acceleration transducer，the design of micro capacitance measurement circuit is based on the key PIC16LF874 chip. Briefly discusses the application of the capacitance measuring circuit for the background and status of foreign researchers，focusing on the United States PIC16LF874 microcontroller features. Capacitive sensor outputed signal through the dynamics of weak PS021-chip capacitors （capacitancedigital converter） to convert analog data into digital data，the measured data from the PIC16LF874 microcontroller application process， display and preservation. Experimental results show that the fixed capacitor 10pF ~ 20pF nominal value of the measured value of relative error is within 1%，but also it canbe seen the value of the measured capacitance larger，measuring value and the nominal value of relative error smaller.
上傳時間： 2013-10-29
上傳用戶：wojiaohs
生活中許多目標(biāo)的高度和水平距離需要進(jìn)行測量。目前主要的測量方法，仍以傳統(tǒng)的皮尺丈量為主，測量效率不高，有時還很不方便，沒有技術(shù)成熟的數(shù)字式測高測距產(chǎn)品。以基本的數(shù)學(xué)方法為理論依據(jù)，利用遙控小車做為載體，采用角度傳感器測量角度、霍爾傳感器測量水平距離等，通過單片機(jī)LM3S615進(jìn)行數(shù)據(jù)計(jì)算，實(shí)現(xiàn)了對待測目標(biāo)物體的高度、水平距離等數(shù)據(jù)的快速、精確和數(shù)字式的測量，高度測量精度可達(dá)99.06%，水平測量精度則可達(dá)98.06%。 Abstract: In our lives， the height and horizontal distance of some goals are needed to be measured. Because the currently used methods are still traditional tape-based measuring methods， and the measuring efficiency is low and inconvenient so some kinds of digital and portable measuring methods or instruments are needed. Based on the basic math theory， this paper designed and manufactured a portable， digital and remote controlled measuring mobile small vehicle， which assembled with angle measuring sensor for angle measurement and Hall sensor for horizontal distance measuring. MCU LM3S615 calculated the height and horizontal distance data gotten from these sensors. The measuring process is simple， the measuring results are more accurate and the measuring efficiency is higher than traditional measure instruments. The accuracy of height and distance measurement can reach 99.06% and 98.06%.
上傳時間： 2013-10-30
上傳用戶：jackandlee
蟲蟲下載站版權(quán)所有 京ICP備2021023401號-1
<strike id="2s2qs"></strike>