接收信號譜 的英文怎麼說
中文拼音 [jiēshōuxìnháopǔ]
接收信號譜
英文
received spectrum- 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 ...
- 收 : Ⅰ動詞1 (把攤開的或分散的事物聚集、合攏) put away; take in 2 (收取) collect 3 (收割) harvest...
- 號 : 號Ⅰ名1 (名稱) name 2 (別號; 字) assumed name; alternative name3 (商店) business house 4 (...
- 譜 : Ⅰ名詞[書面語]1 (按類別或系統編成的書或冊子等) table; chart; register 2 (指導練習的格式或圖形)...
- 接收 : 1 (收受) receive; reception; accept; [電學] receipt; receiving 2 (接管) take over; expropriat...
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Lfmcw radar adopts the receiver with the structure of “ homodyne - fourier ”, and acquires the range spectrum after its if signal is sampled, and then processed by ftt
Lfmcw雷達採用了「差拍-傅立葉」接收機結構,其回波中頻信號經數字採集后進行fft處理,從而獲得雷達的距離譜。The second, the main work in the paper is discussed. they are include : the theory and character of electromagnetic leaking from a computer ; the theory of accumulation mean filter and pectination filter ; the analysis of synchronous signal precision, at 10 - 12 second level, for stably intercepting ; the technology requirement of receiver and data acquisition board for clearly displaying the images recovered from the intercepted data
本文從計算機視頻電磁泄漏和數字濾波器兩方面的基本理論出發,詳細論述了計算機視頻信息電磁泄漏的原理及特點,指出視頻泄漏信息的頻譜是以行頻為周期的譜線;分析了重加濾波器和梳狀濾波器的性能;分析了視頻泄漏信息截獲的條件;推導出穩定截獲視頻泄漏信息需要對同步信號的精度控制在皮秒級;論述了清晰再現對接收機和數據採集卡的技術要求。In recent years, the worldwide researchers pay much attention to fourier telescopy. it is an active imaging technique that encodes the information in the temporal instead of spatial domain, then receives the speckle and deposed of it to reconstruction the object image. now, the high - resolution technique is under the condition of deeply researched
它是一種主動式干涉成像技術,這一技術通過時域內的相位的調制完成直線條紋對目標的掃描,從而達到對深空目標頻譜的抽樣,然後接收其散射回波,對回波信號進行處理,進而還原出目標的像。In this method of measuring time - resolved spectrum, a special light beam modulator translates the time - distribution of an optical spectrum into a space - distribution of light intensity of the light beam, and the space - distribution spectrum is dispersed by a multi - spectrometer, then it is detected by an ordinary 2 - d ccd array detector
瞬態時間分辨譜測量方法的主要思想:使用特殊光束調制器把光譜隨時間的變化過程轉化為光強的空間分佈,經色散后,以二維探測器接收並轉換光信號為電信號,用通用計算機控制採集並處理光譜數據。To utilize the advantages of dsp chips, the system should be computing sources economical. according to digital signal processing theory, the poly - phase fir can help reduce the workloads of the ddc / duc. therefore, adding the complex carrier mixers, the channelization system ( a method of using a single wideband facility to transmit many relatively narrow - bandwidth signals. by subdividing the frequency spectrum used in the wideband channel ) can be formed utilizing the characters of fft
為了使開發出的軟體可以適用於高速dsp器件開發,節省系統資源,課題首先從數字信號處理的理論進行分析,得出可以利用抽樣率轉換的數字濾波器的特點,即多相濾波實現數字上下變頻計算負擔的減小,之後進一步將多相濾波器與頻譜搬移部分結合,通過公式的推導,得出可利用快速傅立葉變換的特點實現多路信號的通道化發射和接收的處理模型。This paper mainly focuses on the noise limiting by means of the direct sequence spread spectrum ( dsss ) and the analysis of the transmission performance of the plc and some digital modulation technology. the contents of the paper is as follows : 1 ) the technical feasibility is proved after simulating noise limiting principle of dsss by means of systemview, the simulation software ; 2 ) a kind of band pass filter ( bpf ) is realized according to the requirement of filter and the principle of butterworth approximation, which satisfies the index of performance of dsss. 3 ) the low voltage plc system includes the sc1128, the specific modulation / demodulation ic, the bpf filter and other circuit components, furthermore, the control function of system is realized by means of the personal computer and the microcontroller
本課題在對低壓電力線的傳輸特性和數字調制技術進行分析的基礎上,將通信理論中的直接序列擴頻技術( dsss )用於解決低壓電力線通信的干擾問題,主要研究內容如下: ( 1 )用通信模擬軟體systemview對dsss技術的通信和抗干擾原理進行模擬分析,分別對時域和頻域下採用dsss技術前後接收信號的頻譜進行分析,驗證dsss技術在本系統中的可行性; ( 2 )由dsss技術對濾波系統的要求,根據濾波理論分析了巴特沃思型濾波器的逼近原理並設計了合適的濾波電路; ( 3 )用調制解調晶元sc1128和自行設計的濾波器加之輔助外圍電路,構造出低壓電力線載波通信系統,並採用atmel公司的單片機設計了接收和發射電路的微控制器; ( 4 )分別對採取抗干擾措施前後輸入和輸出信號進行對比實驗,並對結果進行分析,驗證了dsss技術對干擾信號的抑制作用。Measuring frequency of received signal by a spectrum line ratio method
譜線比值法測量接收信號的頻率3. with comprehensive improvement of transponder including structural adjustment to lna ; optimization of ( phase locked loop ) pll filter ; structural adjustment to the transmitter and phase error adjustment to the intermediate frequency demodulation circuit, we have successfully enhanced sensitivity, expanded dynamic range, increased transmitting power and improved the spectrum purity ; decreased capture time for pll ; improved the signal quality after demodulation ; reduced its volume and power consumption. 4
3 、對通信機的全面改進,包括lna結構的調整、鎖相環環路濾波器的優化、發射部分結構的調整以及中頻解調電路的相差調整,提高了系統的接收靈敏度、改善了本振的頻譜純度、減少了鎖相環的鎖定時間、使中頻解調后的信號質量大為提高,同時還減少了體積、節約了系統的功耗。It was indicated that the major frequency of signals for three different motivating manners concentrated between 20 and 50 khz, the difference between wavelet coefficients was small, and the pertinence of the original signal and the returning signals was low
最終結果表明,從頻譜上來講,三種激勵方式所產生信號的主頻集中在20 50khz ,小波系數相差甚微,並且來源於同一源的接收信號與源信號相關程度也不高。The over - grazing of india ' s spectrum is already beginning to show in dropped calls and patchy reception
在印度,過度開發無線頻譜已經開始導致有效通話次數減少,信號接收不連貫等現象。( 2 ). to study the difference between signals responding to different motivating manners as well as between signals come from the same origin, the different managing manners of wavelet transform, frequency analysis, pertinence analysis and characteristic coefficients of wavelet region for signal information were performed. the effort of trying to distinguish the signals motivated by different manners and to confirm the signal origin through the received information was made
( 2 ) .通過對三種不同激勵方式下產生信號的小波變換、頻譜分析、相關性分析等信號處理方式,研究不同激勵方式下所對應信號之間的差異及來源於同一源的不同接收處信號的差異,以試圖區分不同激勵方式所產生的信號並明確是否可以由所接收的信號來推斷源信號的特徵。Then, we introduce the basic structure of pd weather radar signal processing system and their function of each subsystem, mainly including intermediate frequency receiver, clutter elimination, range correcting and smoothness, ambiguity resolution and spectrum estimation
並在此基礎上介紹了氣象雷達信號處理系統的基本構成與各部分的主要功能,主要包括氣象回波中頻接收、雜波抑制、距離訂正、平滑處理、解模糊和譜矩估計等。This thesis discusses the pulse doppler ( pd ) weather radar signal processing system including digital intermediate frequency ( if ) receiver, especially on the application of if sampling and digital demodulation technique in pd weather radar signal processing system, the influence of amplitude and phase unbalances of in - phase and quadrature channels on weather radar echo spectrum estimation, ground clutters elimination algorithms and a typical engineering realization scheme of pd weather radar signal processing system
本論文研究的是採用數字中頻接收技術的脈沖多普勒氣象雷達信號處理系統,重點研究了中頻采樣及數字解調技術在脈沖多普勒氣象雷達信號處理系統中的應用、正交雙通道幅相不平衡對氣象回波譜估計的影響、地雜波濾波演算法,以及脈沖多普勒氣象雷達信號處理系統的具體工程實現。Qpsk modulation for digital television using advanced digital signal processing technology, full compliance with dvb - s standard, the receiving end can be directly used for receiving digital satellite receiver. it must not only be able to achieve a higher utilization of the spectrum, with a strong anti - jamming and high performance. fm microwave equipment and simulation and will be good compatibility
Qpsk數字電視調制器採用了先進的數字信號處理技術,完全符合dvb - s標準,接收端可直接用數字衛星接收機進行接收。它不但能取得較高的頻譜利用率,具有很強的抗干擾性和較高的性能價格比,而且和模擬fm微波設備也能很好的兼容。Anti - jamming capability of interferometer direction finder with multi channel receiver is analyzed and studied. measures for control co - channel jamming are given : reduce intererence strength by antenna character, change gate level of receiver, alter df bandwidth, make use of the pause function of display and a type of filter
提出了抗同波干擾的若干措施:利用天線的方向圖抑制干擾信號、改變接收信號的門限電平、改變測向帶寬、利用屏幕顯示的暫存功能、倒譜同態濾波方法等。In the second chapter, a wideband mimo channel model with multiple - tap was integrated according to the angle of departure of the transmitting signal and its spread angle, the angle of arrival of the receiving signal and its spread angle, power azimuth spectra, doppler spectrum and the geometric construction of antenna array both sides of transmit and receive, on the basis of full research on the theories of space - time channel model proposed in the recent literature
第二章在對最近文獻中提出的一些空時通道模型理論進行詳細研究的基礎上,根據發射信號的離開角及其擴展角、接收信號的到達角及其擴展角、功率方位譜、多普勒譜和收發兩端天線的拓撲結構,綜合了一個多抽頭的寬帶mimo通道模型。Firstly, according to the characteristic that the doppler frequency shift signal can be approximated as a single sinusoid signal, the extended sinusoid signal retrieval ( pisarenko and esprit ) methods are presented and signal state and measurement formulations are developed, so the kalman filter recursive method is got. the brief introduction of low velocity moving target doppler frequency shift signal wigner - ville transformation and wavelet transformation expression are presented in this paper. secondly, because the clutter is gaussian distribution, cumement and high - order spectrum based methods are presented and the simulation results prove their good performance to suppress gaussian clutter in low velocity moving target doppler frequency shift signal processing
一個方面是根據低速目標的多普勒信號可簡化為單一正弦波形式這一特點,得到了擴展的高斯色噪聲背景下的諧波恢復演算法,即高斯色噪聲中的pisarenko諧波恢復法和旋轉因子不變法( esprit ) ;並推導了信號的狀態方程和觀測方程,進而得到基於卡爾曼濾波的遞推演算法對信號進行提取;本文還簡單的介紹了低速運動目標的多普勒頻移信號的wigner - ville變換與小波變換;另一個方面是針對雜波服從高斯分佈這一特點,提出了對接收信號求累積量和高階譜來對高斯雜波進行抑制。Firstly, the theory and the architecture of hardware system are described, secondly, the steps of the signal processing are discussed in detail. based on the experiments and the characteristics of the signal, we pre - process the signals with band - pass filter, proportional amplifier and coherent demodulator. after sampling and analysis doppler information, we display the final results distinctly to alarm in time
然後,結合系統中各主要部分的任務,詳細介紹了信號處理的各個步驟:通過實驗比較,並結合接收信號的特點,選用帶通濾波器、比例放大器、相干檢波等技術對信號進行預處理;然後對獲得的多卜勒信息進行采樣和頻譜分析;最後,用比較直觀的形式顯示數據結果,以及時準確地告警。The accurately controlled signal source generates sinusoidal elastic wave accurately controlled in frequency and stable in phase to " illustrate " underground media. time signal stacker receive signal by stacking and doing fft to measure the transfer function of media. " sompi " cepstrum method retrieve group velocity travel times and decayed factors of wave element from observational data of transfer function in a limited frequency window
精密可控震源用於產生頻率精確相位穩定的正弦彈性波以照射地層內部,信號疊加器通過對接收信號進行疊加和進行傅立葉變換的方式實現對介質傳遞函數的精密測量, 「存否」倒譜方法能夠根據一段窄帶頻域傳遞函數數據獲得時域上各個波成分的群速度傳播時間和介質衰減因子。Firstly, in wireless environment, receiver has no know the time delay between transmitter and itself. in ofdm system, ofdm data is transmitted as one symbol, so in order for correct demodulation, the correct start of symbol should be got from ofdm system to reduce the effect of isi. secondly, the high frequency utilization in ofdm is based on the orthogonal properties of sub carriers. if frequency offset is generated, the orthogonal properties among sub carriers will lost, that will cause inter carrier interference ( ici ) and high ber of system
Ofdm技術也存在著一些缺陷,首先,在無線環境中傳輸的ofdm信號對定時要求高,為了減少碼間串擾( isi )影響,必須從接收信號中提取出正確的符號起始位;其次, ofdm系統對頻率偏移敏感, ofdm技術的高頻譜利用率和傳輸可靠性均以子載波的正交性為基礎,如果接收機和發射機之間發生頻率偏移,子載波之間就會失去正交性,導致嚴重的子載波間干擾( ici ) ,降低系統性能。分享友人