1 Noise enhanced binary hypothesis-TESTING in a new framework
標(biāo)簽: hypothesis-TESTING enhanced binary Noise
上傳時(shí)間: 2016-06-02
上傳用戶:siguazgb
音頻管理組件(Audio Management Unit,AMU)是先進(jìn)客艙娛樂(lè)與服務(wù)系統(tǒng)(Advanced Cabin Entertainment Service System,ACESS)的組成部分,應(yīng)用于飛機(jī)上音頻資源的管理與控制。飛機(jī)運(yùn)營(yíng)對(duì)航空機(jī)載電子系統(tǒng)準(zhǔn)確性、復(fù)雜性和安全性的高要求,使得其維修維護(hù)工作極大地依賴于自動(dòng)測(cè)試設(shè)備(Automatic TESTING Equipment,ATE)。本課題來(lái)源于實(shí)際工程項(xiàng)目, FPGA技術(shù)具備多種優(yōu)點(diǎn),將其與民航測(cè)試設(shè)備結(jié)合研制一個(gè)用于檢測(cè)AMU故障的自動(dòng)測(cè)試系統(tǒng),該系統(tǒng)將對(duì)AMU自動(dòng)完成部件維修手冊(cè)(Comvonent Maintenance Manual,CMM)所規(guī)定的全部功能、性能方面的綜合測(cè)試。 本文首先概述音頻管理組件、自動(dòng)測(cè)試系統(tǒng)及其在民航領(lǐng)域的應(yīng)用,并闡述了課題的背景、研究目標(biāo)和相關(guān)技術(shù)要求;文章對(duì)可編程邏輯器件CPLD/FPGA的結(jié)構(gòu)原理、硬件描述語(yǔ)言VHDL的特點(diǎn)以及MAXL+plusⅡ軟件的設(shè)計(jì)流程進(jìn)行了說(shuō)明,重點(diǎn)闡述了基于FPGA的DDS信號(hào)發(fā)生器以及數(shù)據(jù)采集卡的設(shè)計(jì)實(shí)現(xiàn)、并著重闡述了ARINC429總線的傳輸規(guī)范,和基于FPGA的ARINC429總線接口的設(shè)計(jì)與實(shí)現(xiàn)。在ARINC429接口設(shè)計(jì)中采用自頂向下,多層次系統(tǒng)設(shè)計(jì)的方法,用VHDL語(yǔ)言進(jìn)行描述。在發(fā)送器中利用了FPGA內(nèi)部的分布式RAM創(chuàng)建異步FIFO,節(jié)約了FPGA的內(nèi)部資源和提高了數(shù)據(jù)傳輸速度;在接收器中采用了提高抗干擾性的優(yōu)化設(shè)計(jì)。測(cè)試結(jié)果表明基于FPGA的設(shè)計(jì)實(shí)現(xiàn)ARINC429總線數(shù)據(jù)通信的要求,使用方便,可靠性好,能夠克服HS-3282芯片中的數(shù)據(jù)格式固定,使用不夠靈活方便,價(jià)格昂貴的缺點(diǎn)。
標(biāo)簽: FPGA 飛機(jī) 音頻 測(cè)試系統(tǒng)
上傳時(shí)間: 2013-08-06
上傳用戶:gzming
磁芯電感器的諧波失真分析 摘 要:簡(jiǎn)述了改進(jìn)鐵氧體軟磁材料比損耗系數(shù)和磁滯常數(shù)ηB,從而降低總諧波失真THD的歷史過(guò)程,分析了諸多因數(shù)對(duì)諧波測(cè)量的影響,提出了磁心性能的調(diào)控方向。 關(guān)鍵詞:比損耗系數(shù), 磁滯常數(shù)ηB ,直流偏置特性DC-Bias,總諧波失真THD Analysis on THD of the fer rite co res u se d i n i nductancShi Yan Nanjing Finemag Technology Co. Ltd., Nanjing 210033 Abstract: Histrory of decreasing THD by improving the ratio loss coefficient and hysteresis constant of soft magnetic ferrite is briefly narrated. The effect of many factors which affect the harmonic wave TESTING is analysed. The way of improving the performance of ferrite cores is put forward. Key words: ratio loss coefficient,hysteresis constant,DC-Bias,THD 近年來(lái),變壓器生產(chǎn)廠家和軟磁鐵氧體生產(chǎn)廠家,在電感器和變壓器產(chǎn)品的總諧波失真指標(biāo)控制上,進(jìn)行了深入的探討和廣泛的合作,逐步弄清了一些似是而非的問(wèn)題。從工藝技術(shù)上采取了不少有效措施,促進(jìn)了質(zhì)量問(wèn)題的迅速解決。本文將就此熱門話題作一些粗淺探討。 一、 歷史回顧 總諧波失真(Total harmonic distortion) ,簡(jiǎn)稱THD,并不是什么新的概念,早在幾十年前的載波通信技術(shù)中就已有嚴(yán)格要求<1>。1978年郵電部公布的標(biāo)準(zhǔn)YD/Z17-78“載波用鐵氧體罐形磁心”中,規(guī)定了高μQ材料制作的無(wú)中心柱配對(duì)罐形磁心詳細(xì)的測(cè)試電路和方法。如圖一電路所示,利用LC組成的150KHz低通濾波器在高電平輸入的情況下測(cè)量磁心產(chǎn)生的非線性失真。這種相對(duì)比較的實(shí)用方法,專用于無(wú)中心柱配對(duì)罐形磁心的諧波衰耗測(cè)試。 這種磁心主要用于載波電報(bào)、電話設(shè)備的遙測(cè)振蕩器和線路放大器系統(tǒng),其非線性失真有很嚴(yán)格的要求。 圖中 ZD —— QF867 型阻容式載頻振蕩器,輸出阻抗 150Ω, Ld47 —— 47KHz 低通濾波器,阻抗 150Ω,阻帶衰耗大于61dB, Lg88 ——并聯(lián)高低通濾波器,阻抗 150Ω,三次諧波衰耗大于61dB Ld88 ——并聯(lián)高低通濾波器,阻抗 150Ω,三次諧波衰耗大于61dB FD —— 30~50KHz 放大器, 阻抗 150Ω, 增益不小于 43 dB,三次諧波衰耗b3(0)≥91 dB, DP —— Qp373 選頻電平表,輸入高阻抗, L ——被測(cè)無(wú)心罐形磁心及線圈, C ——聚苯乙烯薄膜電容器CMO-100V-707APF±0.5%,二只。 測(cè)量時(shí),所配用線圈應(yīng)用絲包銅電磁線SQJ9×0.12(JB661-75)在直徑為16.1mm的線架上繞制 120 匝, (線架為一格) , 其空心電感值為 318μH(誤差1%) 被測(cè)磁心配對(duì)安裝好后,先調(diào)節(jié)振蕩器頻率為 36.6~40KHz, 使輸出電平值為+17.4 dB, 即選頻表在 22′端子測(cè)得的主波電平 (P2)為+17.4 dB,然后在33′端子處測(cè)得輸出的三次諧波電平(P3), 則三次諧波衰耗值為:b3(+2)= P2+S+ P3 式中:S 為放大器增益dB 從以往的資料引證, 就可以發(fā)現(xiàn)諧波失真的測(cè)量是一項(xiàng)很精細(xì)的工作,其中測(cè)量系統(tǒng)的高、低通濾波器,信號(hào)源和放大器本身的三次諧波衰耗控制很嚴(yán),阻抗必須匹配,薄膜電容器的非線性也有相應(yīng)要求。濾波器的電感全由不帶任何磁介質(zhì)的大空心線圈繞成,以保證本身的“潔凈” ,不至于造成對(duì)磁心分選的誤判。 為了滿足多路通信整機(jī)的小型化和穩(wěn)定性要求, 必須生產(chǎn)低損耗高穩(wěn)定磁心。上世紀(jì) 70 年代初,1409 所和四機(jī)部、郵電部各廠,從工藝上改變了推板空氣窯燒結(jié),出窯后經(jīng)真空罐冷卻的落后方式,改用真空爐,并控制燒結(jié)、冷卻氣氛。技術(shù)上采用共沉淀法攻關(guān)試制出了μQ乘積 60 萬(wàn)和 100 萬(wàn)的低損耗高穩(wěn)定材料,在此基礎(chǔ)上,還實(shí)現(xiàn)了高μ7000~10000材料的突破,從而大大縮短了與國(guó)外企業(yè)的技術(shù)差異。當(dāng)時(shí)正處于通信技術(shù)由FDM(頻率劃分調(diào)制)向PCM(脈沖編碼調(diào)制) 轉(zhuǎn)換時(shí)期, 日本人明石雅夫發(fā)表了μQ乘積125 萬(wàn)為 0.8×10 ,100KHz)的超優(yōu)鐵氧體材料<3>,其磁滯系數(shù)降為優(yōu)鐵
上傳時(shí)間: 2014-12-24
上傳用戶:7891
為了改變目前電網(wǎng)現(xiàn)場(chǎng)作業(yè)管理的變電巡檢、變電檢修試驗(yàn)、輸電線路巡檢檢修等管理系統(tǒng)各自獨(dú)立運(yùn)行,信息不能共享,功能、效率受限,建設(shè)和維護(hù)成本高的現(xiàn)狀,提出了采用B/S+C/S構(gòu)架模式,將各現(xiàn)場(chǎng)作業(yè)管理模塊和生產(chǎn)MIS(管理系統(tǒng))集成為一體的現(xiàn)場(chǎng)作業(yè)管理系統(tǒng)的設(shè)計(jì)方案,做到各子系統(tǒng)和生產(chǎn)MIS軟硬資源共享,做到同一數(shù)據(jù)唯一入口、一處錄入多處使用。各子系統(tǒng)設(shè)備人員等基礎(chǔ)信息來(lái)源于生產(chǎn)管理系統(tǒng),各子系統(tǒng)又是生產(chǎn)管理系統(tǒng)的作業(yè)數(shù)據(jù)、缺陷信息的重要來(lái)源。經(jīng)過(guò)研究試用成功和推廣應(yīng)用,目前該系統(tǒng)已在江西電網(wǎng)220 kV及以上變電站全面應(yīng)用。 Abstract: In order to improve the status that the substation field inspection system, substation equipments maintenance and TESTING system, power-line inspection and maintenance system are running independent with each other. They can?蒺t share the resource information which accordingly constrains their functions and efficiency, and their construction and maintenance costs are high. This paper introduces a field standardized work management system based on B/S+C/S mode, integrating all field work management systems based on MIS and share the equipments and employee?蒺s data of MIS,the field work data of the sub systems are the source information of MIS, by which the same single data resouce with one-time input can be utilized in multiple places. After the research and TESTING, this system is triumphantly using in all 220kV and above substations in Jiangxi grid.
標(biāo)簽: 電網(wǎng) 信息化 管理系統(tǒng)
上傳時(shí)間: 2013-11-15
上傳用戶:han_zh
Designing Boards with Atmel AT89C51,AT89C52, AT89C1051, and AT89C2051 for Writing Flash at In-Circuit Test. Recent improvements in chips and testers have made it possible for the tester to begin taking over the role tradi-tionally assigned to the PROM program-mer. Instead of having a PROM pro- grammer write nonvolatile memories before assembling the board, the in-cir- cuit tester writes them during in-circuit TESTING operations. Many Teradyne Z18- series testers are now in use loading code into nonvolatile memories, micro- controllers and in-circuit programmable logic devices. The purpose of this note is to explain how the Z18 approaches the writing task for Atmel AT89C series IC’s, so that designers of boards using these chips can get the best results.
上傳時(shí)間: 2013-11-17
上傳用戶:xiaozhiqban
以C8051F020為核心處理器,設(shè)計(jì)無(wú)線傳感器網(wǎng)絡(luò)數(shù)據(jù)采集系統(tǒng)。系統(tǒng)采用SZ05-ADV型無(wú)線通訊模塊組建Zigbee無(wú)線網(wǎng)絡(luò),結(jié)合嵌入式系統(tǒng)的軟硬件技術(shù),完成終端節(jié)點(diǎn)的8路傳感器信號(hào)的數(shù)據(jù)采集。現(xiàn)場(chǎng)8路信號(hào)通過(guò)前端處理后,分別送入C8051F020的12位A/D轉(zhuǎn)換器進(jìn)行轉(zhuǎn)換。經(jīng)過(guò)精確處理、存儲(chǔ)后的現(xiàn)場(chǎng)數(shù)據(jù),通過(guò)Zigbee無(wú)線網(wǎng)絡(luò)傳送到上位機(jī),系統(tǒng)可達(dá)到汽車試驗(yàn)中無(wú)線測(cè)試的目的。 Abstract: This paper designs a wireless sensor network system for data acquisition with C8051F020 as core processors.The system used SZ05-ADV wireless communication module,set up a Zigbee wireless network, combined with hardware and software technologies of embedded systems,completed the end-node 8-locale sensor signal data acquisition.Eight locale signals were sent separately into the 12-bit ADC of C8051F020 for conversion through front treatment.After accurate processing and storage,the locale data was transmitted to the host computer through Zigbee wireless.The system achieves the purpose of wireless TESTING in vehicle trial.
標(biāo)簽: C8051F020 Zigbee 汽車測(cè)試 系統(tǒng)設(shè)計(jì)
上傳時(shí)間: 2013-11-23
上傳用戶:dsgkjgkjg
飛機(jī)電網(wǎng)故障時(shí),機(jī)載電氣盒必須在延遲時(shí)間內(nèi)切斷電網(wǎng),保護(hù)機(jī)載設(shè)備。采用AT89S52設(shè)計(jì)的電氣盒測(cè)試儀能夠測(cè)試電氣盒保護(hù)功能,測(cè)量延遲時(shí)間。實(shí)際應(yīng)用結(jié)果表明,該測(cè)試儀具有測(cè)量準(zhǔn)確、可靠性高、成本低等優(yōu)點(diǎn)。 Abstract: The helicopter-electrical-box must shut off the helicopter power,protect the equipments of the helicopter when the helicopter power is failed.The tester for the helicopter-electrical-box based on AT89S52is used for TESTING the protect-ing function and measuring the delay time.Application results show this tester has some advantages,such as accurate mea-surement,high dependability,economical cost etc.
上傳時(shí)間: 2014-12-27
上傳用戶:786334970
介紹基于ISA總線與KH-9300的數(shù)據(jù)采集板卡的設(shè)置,詳細(xì)說(shuō)明8254定時(shí)計(jì)數(shù)器及8259中斷控制器的結(jié)構(gòu)特點(diǎn)、工作方式、控制字等,探討中斷類型、中斷處理程序、中斷矢量表及其填寫(xiě)。重點(diǎn)講述使用TorboC編寫(xiě)中斷服務(wù)程序的方法,應(yīng)注意的主要問(wèn)題及程序測(cè)試的結(jié)果。 Abstract: The settings of KH-9300 data acquisition board based on the ISA bus is introduced,the structural characteristics,working methods,control characters of the timing counter 8254 and interruptioncontroller 8259 are explained in detail.The interruption type,interrupt handling programs,interruption vector table and its filling also are discussed.Further,great emphasis is put on the method of interrupt service program compiled by Torbo C,the main issues that should be noted,and the results of program TESTING.
上傳時(shí)間: 2013-11-14
上傳用戶:qq527891923
該系統(tǒng)由單片機(jī)89S52控制模塊,程控寬帶放大模塊,整形模塊,F(xiàn)PGA內(nèi)頻率、相位差測(cè)量模塊等構(gòu)成,采用等精度測(cè)頻法測(cè)出頻率和周期,可測(cè)量有效值為0.01~5V,頻率范圍1Hz~20MHz信號(hào)的頻率、周期信號(hào),精度高達(dá)10-6。采用計(jì)數(shù)法測(cè)量相位差,該系統(tǒng)可測(cè)量有效值0.5~5V,頻率10Hz~100kHz信號(hào)的相位差,精度為1°。系統(tǒng)功能由按鍵控制,測(cè)量結(jié)果實(shí)時(shí)顯示,人機(jī)界面友好。 Abstract: The system consists of the following functional blocks:89S52microcontroller controlling module,programmable amplifier module,comparator module,frequency and phase difference TESTING module in the FPGA.The system use the equal accuracy frequency-examining technique it measures frequency and circle of signal which its ranges is from1Hz to20MHz and the amplitude of which its range is from0.01Vrms to5Vrms,precision is up to10-6.Using of count method,the system detects the phase difference of signal,the amplitude of whic its range is from0.5Vrms to5Vrms and the frequency of which its ranges is from10Hz to100kHz,precision is up to1°,The system functions is controlled by certain keys,measurement results are displayed in real-time and it is friendly interface.
標(biāo)簽: 89S52 單片機(jī) 多功能 計(jì)數(shù)器
上傳時(shí)間: 2013-11-04
上傳用戶:CHINA526
為了解決磁放大器性能測(cè)試過(guò)程中,需要對(duì)其供給不同數(shù)值恒定電流的問(wèn)題,設(shè)計(jì)了一種基于DAC7512和單片機(jī)的數(shù)控恒流源系統(tǒng)。該系統(tǒng)采用AT89C51作為主控器件,將計(jì)算機(jī)發(fā)送的電流控制字命令轉(zhuǎn)換為D/A轉(zhuǎn)換器控制字,通過(guò)模擬SPI通信接口,寫(xiě)D/A控制字到DAC7512,從而控制其輸出相應(yīng)數(shù)字電壓值,經(jīng)差動(dòng)縮放電路、電壓/電路變換電路和功率驅(qū)動(dòng)電路,最后輸出恒定電流。實(shí)驗(yàn)結(jié)果表明,恒流源輸出電流調(diào)節(jié)范圍為-45~+45 mA、精度為±0.1 mA,分辨率達(dá)0.024 4 mA,具有應(yīng)用靈活,外圍電路簡(jiǎn)單,可靠性高的特點(diǎn)。該數(shù)控直流恒流源也可為相關(guān)產(chǎn)品的測(cè)試系統(tǒng)研發(fā)提供參考。 Abstract: In order to solve the need to supply different values constant current for the magnetic amplifier in TESTING process, numerical control constant current source system was designed based on DAC7512 chip and microcontroller technology. The system used the AT89C51 as the main chip, which can convert the current control word from computer into to D/A control words. And the system wrote D/A control word into the DAC7512 chip to control the output voltage value by the SPI communication interface, which can output corresponding constant current figures by scaling circuit, the V/I converter and power drive circuit. Experimental results show that the current source output current adjustment range is -45~+45mA, accuracy is ± 0.1mA, and resolution ratio is 0.024 4mA
標(biāo)簽: 7512 DAC 數(shù)控直流 恒流源
上傳時(shí)間: 2014-12-27
上傳用戶:invtnewer
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