直接調頻 的英文怎麼說
中文拼音 [zhíjiēdiàobīn]
直接調頻
英文
direct frequency modulation- 直 : Ⅰ形容詞1 (成直線的; 硬挺的) straight; stiff 2 (跟地面垂直的; 從上到下的; 從前到后的) erect; v...
- 接 : Ⅰ動詞1 (靠近;接觸) come into contact with; come close to 2 (連接; 使連接) connect; join; put ...
- 調 : Ⅰ動詞1 (配合得均勻合適) harmonize; suit well; fit in perfectly 2 (使配合得均勻合適) mix; adju...
- 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...
- 直接 : direct; immediate
- 調頻 : frequency modulation (fm); frequency adjustment調頻磁帶錄音機 f m magnetic tape recorder; 調頻...
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This is a computerised voice communication system between pilots and air traffic controllers, and between air traffic control positions in the air traffic control centre, aerodrome control tower, rescue coordination centre and aeromobile centre by using pre - set switching and distribution of various aeronautical frequencies and direct communication lines. the new computerised system will enhance the overall efficiency in communications
讓機師與管制員之間,或航空交通管制中心、指揮塔、援救協調中心和航空通訊中心內各不同管制崗位之間,能用預先設定的系統作直接通話,包括可轉換和發布的航空通訊頻道和直接通訊線路等。The transducer speed adjustment is used for the conveyer belt and the brush wheel, and the motor starts to rotate directly to make the machine run more smoothly and the stain done more uniformly
輸送帶,毛刷輪採用變頻器調速,馬達直接轉動,使得機器運轉更為順暢,著色更為均勻。A multi - wavelet packets modulation based on ds - ss
基於直接擴頻的多小波包調制In this paper, research on the algorithm of complete digital if and baseband transmission system and the realization of transmitter and receiver. / 4 - dqpsk is chosen as digital modulation scheme. the scheme of demodulation is baseband differential detection. sliding correlator can realize the symbol synchronous acquisition ; early - late gate synchronizer is used to do symbol synchronous tracking
系統的發射機選定/ 4 - dqpsk為調制方式,接收機採用基帶差分解調的非相干解調方式,滑動相關器捕獲發送的pn序列,早遲門同步器跟蹤符號同步,使用相關器對同步后的符號進行最佳判決,並在這些演算法實現的基礎上,實現了直接序列擴頻和解擴技術。Instrumentation magnetic tape ; direct and fm recording
測量儀器磁帶.直接和調頻錄制In attempt to directly compare the sound response characters of the same bf neurons or different bf neurons and their interactive relation, the double recording microelectrodes were penetrated into two different neurons in iso - frequnency laminas or hetero - frequency laminas. taking advantage of frequency tonotopical arrangement in 1c of bats, it was explored how the neurons integrated different parallel processes of the same sound information. in the case of which, we hoped to explore the relation between the sound response characters of the central auditory neurons and neural modulation in background noise for the further understanding of the mechanism in the central auditory neurons extracting sound signals
本研究以大棕蝠( bigbrownbat , eptesicusfuscus )為模型,利用ic聲調組構排列成同頻層這一結構特點,突破單電極記錄和檢測神經元的方法,同時推進兩單電極至一個同頻層或兩個同頻層的兩個不同神經元,試圖從細胞水平直接比較兩個具有相同和不同最佳頻率的神經元聲信號的加工處理特徵、以及它們之間的相互關系,以期窺探它們在對同一聲信號處理過程中的整合奧秘,並以此為基礎分析和探討背景噪聲條件下中樞神經元聲反應特徵與神經調制的關系,以期進一步了解中樞聽神經元聲信號提取的機制。As an example, the detection problem of noise frequency modulation jamming signal was analyzed, two accumulation detection methods, direct accumulation detection and binary accumulation deteceion, were proposed, and the detection probability of the two methods was calculated
摘要以噪聲調頻干擾為例,對干擾信號的檢測問題進行了分析,提出直接積累檢測和二進制積累的檢測方法,並計算了兩種方法的檢測概率。Fpga and dvb standard are introduced firstly, dvb - c standard and composition of its system are analyzed completely, development of modulator structure and dvb - c digital modulator composition are presented, more over, analysis of respective modular are given. then, principle of dvb - c digital modulator system are presented, they are error control technique 、 mqam 、 nyquist rule and root raised cosine filter 、 window design method for fir filter 、 multi - rate signal processing ( integer interpolating, conversion of fractional sampling, equal conversion of net structure, polyphase structure for filter, poly - phase structure for interpolator, multi - stage implementation of samplying conversion ) 、 distrubited algorithm 、 cic filter 、 dds 、 cordic algorithm
接著,專門利用一個章節闡述了dvb - c前端調制系統原理,他們了差錯控制技術、多進制調制( mqam ) 、 nyquist準則與平方根升餘弦濾波器、有限沖擊響應濾波器的窗函數設計法、多抽樣率信號處理包括(整數倍內插原理、分數倍抽樣率轉換、網路結構的等效結構、濾波器的多相表示、內插器的多相表示、抽樣率轉換的多級實現) 、分散式演算法、 cic濾波器、直接數字頻率合成( dds ) 、 cordic演算法。According to the theoretical parameters and analysis of clustering identification of noises, and based on the theory of spread frequency communication and bpsk, the remote reading meter system through medium - voltage power line is realized
根據理論參數及噪聲分類識別分析,以直接序列擴頻通信為理論基礎,採用bpsk調制解調,設計了基於中壓電力線的遠程抄表系統。The carrier wave is modulated directly by the baseband signal at several frequency point in l band and s band. firstly, this paper clarifies the theory of i / q modulation, elaborates evm and acpl, and analyzes the effect of amplitude and phase unbalance and dc offset on evm. secondly we review the basic principle of phase locked loop and it ’ s composing parts, including the basic conception and design method of pll frequency synthesizer, especially introduce the charge pump pll frequency synthesizer in detail
首先,在闡述i / q正交調制基本原理的基礎上,通過對誤差矢量和鄰近通道功率泄漏的詳細分析,定性、定量地討論了各種非理想電路因素(如相位不平衡、幅度不平衡、直流偏差等)對調制器性能的影響;其次,介紹了鎖相環的工作原理和基本組成部分,包括鎖相環的設計和環路濾波器的設計,特別詳述了電荷泵鎖相頻率源;第三,介紹了採用直接調制技術模擬衛星信號的射頻前端的設計;最後,對整個直接射頻調制系統進行測試,結果基本上達到了課題要求。The strategy of direct torque control is one of the variable frequency speed control scheme, which was developed in 1985 by prof. depenbrock and which was one of high performance control of induction motor drives after vector control
1985年德國學者depenbrock提出了異步電動機的直接轉矩控制( directtorquecontrol )變頻調速思想, dtc是繼矢量控制之後發展起來的一種高性能交流調速技術。By complementing the proposed scheme with methods to estimate the fractional code delay, the acquisition unit an provide high quality delay estimates such that it can instead of the delay locked loop in the traditional ds receiver. after dispreading successfully, this dissertation introduces a method to estimate the doppler - shift directly from some samples based maximum likelihood estimation, and then revise it forwardly
在成功解擴之後,本文利用最大似然估計從l個樣點中直接估計出殘余多普勒頻偏,並進行前向頻偏校正,來代替傳統擴頻接收機中的科斯塔斯環,經模擬證明該方法的估計精度完全滿足解調的要求。In this paper, microwave t / r front - end for short distance wireless communication is realized in miniature based on low cost mcm - l technology. the main jobs are as follows : 1. the performances of i / q modulation and direct converter receiver are analyzed to set down the system scheme
主要工作包括以下幾個方面: 1 .基於目前流行的數字中頻接收技術,分析了i / q調制和直接變頻接收機的性能,提出超外差變頻的總體系統方案。Abstract : this paper pointed out a few problems of series, harmonic and efficiency etc., to be needed considering, it introduced constructed by all - controlling power electronics device igbt by means of multi - pwm control technology, and this kind of convertor can be the used for direct frequency conversion governorof midolle / high - voltagea. c mo tors
摘要:提出用於高壓電動機變頻調速電源需考慮的串聯、諧波和效率等幾個問題;介紹由全控型電力電子器件igbt按多重化pwm控制技術構成、目前已商品化的高壓變頻器,可用於中、高壓交流電動機的直接變頻調速。Direct modulator converts baseband signal to rf signal without upconvertion. the system design is relatively simple compared to upconversion. so direct modulator provides adventages of compact size, low cost and low spurious response
直接調制將基帶信號直接轉換為射頻信號,不需要二次頻率變換,與上變頻方式相比系統結構簡單,降低了對濾波器的要求,具有體積小,重量輕,成本低等明顯的優點。The transmitter adopt qam modulation mode, which is a directly modulation upper frequency conversion mode, which could afford more high bit rate transmission in the same bandwidth compared to other modulation mode
發射機採用數字式調制方式,即qam直接調制上變頻方式,相對于其它調制方式可以實現在相同帶寬下的高碼率傳輸。Virtual call speculation if a virtual call, or other call through a function pointer, frequently targets a certain function, a profile - guided optimization can insert a conditionally - executed direct call to the frequently - targeted function, and the direct call can be inlined. register allocation
虛調用推理如果某個虛調用或其他通過函數指針的調用頻繁指向特定的函數,按配置優化可以將一個按條件執行的直接調用插入這個頻繁指向的函數,並且可以內聯該直接調用。Aiming to achieve mini - type designment, and transmitting farther on the setting frequency band, direct frequency modulation is chosen after comparing the advantage of amplitude modulation with that of frequency modulation
為了實現微小型化的設計,並且使系統在設定的傳輸頻段上傳輸距離較遠,在比較調幅與調頻的優缺點后,我們選擇了直接調頻的調制方式。The test results demonstrated the feasible of the scheme. the technique researched in this paper will largely simplify the equipment of modulation and demodulation, and may find its application in millimeter wave in high - speed data communication link
與中頻調制方案和一般直接射頻調制方案相比,本文所採用的技術大大簡化了調制/解調設備,同時保持了優良的性能,對毫米波高速數據通信鏈路應用具有較大的優越性和廣闊的前景。The primary work in this dissertation : ( 1 ) the principle, design and implementation of generating lfm / nlfm signals based on direct digital synthesis ( dds ) technology have been discussed especially, the system has been implemented all by author
本文的主要工作之處在於: ( 1 )討論了基於直接數字合成( dds )技術產生直接中頻線性調頻脈壓信號和非線性調頻脈壓信號的工作原理、設計思想和工程實現方法,並獨立完成了系統的工程實現。分享友人