spread-spectrum 中文意思是什麼

spread-spectrum 解釋
擴展頻譜
  • spread : vt (spread)1 伸開,伸長(手臂等),展開,張開(帆等),打開(地圖等);鋪開(氈子等),展寬,展...
  • spectrum : n. (pl. -tra )1. 【物理學】譜,光譜;波譜;能譜,質譜。2. 【無線電】射頻頻譜;無線電(信號)頻譜。3. 【心理學】(眼睛的)余像;殘像。4. 〈轉義〉范圍,幅度;(連續的)系列。
  1. The spread spectrum communication with an aperiodic pn code and under strong man - made jammers has an important significance in military communications

    強人為干擾環境下的非周期擴頻碼的擴頻通信在軍事上具有重要的意義。
  2. Application study on low - voltage power line carrier wave spread spectrum communication system

    低壓電力線載波擴頻通信系統的應用研究
  3. Technique of transmitting data via power line ( pl ) , a new technique developed in recent years , is used to automatize the free collecting system in public service and the management of uptown service 。 this article discussed the advantage , disadvantage and the current state of the power line carrier communication 。 the advantage , method and current state of using spread spectrum technique in power line communication are discussed 。 then the characteristic of low voltage power network was also compendious analyzed 。 in this paper , after introducing the principle of ssc , design of hardware and software of the system are been discussed 。 this system has been put into use , the result has proved its high stability and reliability

    本文研究旨在提供一種利用低壓電力供電網路、低成本、高可靠地實現公共事業收費自動化和小區物業管理智能化的技術應用。討論了電力線載波通信的優、缺點及現狀,擴頻技術在電力線載波通信應用的優點、方式和現狀,並對低壓電力線網路的特性進行了簡單的分析。在闡述了擴頻通信的基本原理的基礎上,本文詳細地介紹了電力載波遠程抄表系統的具體實現,包括硬體模塊和管理軟體本系統已投入運行,具有較高的穩定性和可靠性。
  4. An icr - based spread spectrum communication with arbitrary rate

    的任意傳輸速率擴頻通信系統
  5. The thesis analyzes the transmitting characteristic of the uwa channel, derives the propagation losses, eigenrays and channel impulse responses of uwa channel by use of the kraken normal wave mode and the ray trace algorithm based on velocity - depth curvilinear profile approximation. based on the analysis, a scheme of auto - replying lduwarc system by means of spread spectrum technique has been designed

    論文首先分析了遠程聲遙控通道傳輸特性,分別利用kraken簡正波和射線跟蹤模型對深海和淺海水聲通道的傳輸特性進行分析,對通道的多徑結構、衰落和環境噪聲進行了計算,並在此基礎上設計了基於擴頻技術的自主應答式遠程聲遙控系統方案。
  6. Finally, with the optimized chaos sequences, the results of software simulation on vhf - rc indicates that ds - ss outbalances the bpsk system without spread spectrum due to ber and the ds - ss with kent sequence is better than the one with golden sequence in some extend

    最後本文對數字混沌序列進行了優選,在超短波中繼通道模型上的模擬結果表明混沌直擴通信相比于非擴頻的bpsk通信在誤碼率方面明顯較低;相對于線性擴頻碼( gold序列) ,同樣誤碼率較低。
  7. Spatiotemporal chaos - based stream spread spectrum

    時空混沌流擴頻
  8. The spread spectrum sequences based on spatiotemporal chaotic systems

    基於時空混沌的擴頻序列產生方法
  9. Spread spectrum modulation ssm

    擴頻調制
  10. The nonlinear filtering for nbi estimate - subtract assumes that the prediction error is dominated by spread spectrum signal and the background noise power is far below spread spectrum chip power, this assumption promises the low error ratio of chip decision but may not be attainable to digitalized dsss receiver in military communication environment, and does not coincide with the principle of dsss communication that decreases bit error ratio ( ber ) depending on spread spectrum gain, not on chip power

    在干擾估計抵消濾波中,以往的非線性濾波要求干擾抵消濾波后擴頻信號功率遠大於殘余噪聲功率,進而假設碼片判決的誤碼片率基本為零,這一要求對軍用擴頻通信是不利的,而且也不符合擴頻通信利用擴頻增益降低誤碼率的原則。
  11. The manner of modulation, the spread spectrum codes, and the manner of the acquisition and tracking are discussed. barker codes, dpsk and match filter with the ability of rapid acquisition are concluded as the appropriate manner for cdma missile controlling and guiding

    對擴頻碼、調制解調方式、捕獲與跟蹤方式進行討論,得出barker碼、 dpsk 、匹配濾波器快速捕獲是適合便攜式反坦克導彈cdma無線制導的相應工作方式。
  12. Then studies a peculiar multi - carrier direct sequence spread spectrum ( mc - ds - cdma ) technology, analyzes the methods of processing multi - carrier signals and study the mathematical module of multi - carrier communication system receiver

    然後對本文所研究的這種特殊的多載波直接序列擴頻技術進行闡述,分析了多載波信號處理的方法和研究了多載波接收機的數學模型。
  13. Frequency - hopping ( fh ) is a novel spread spectrum communication technique, which develops very fast in military field due to its lpi / lpd ( low probability of intercept / detection ) properties and immunity against interferences, the extensive application of hf ( high frequency ) frequency - hopping radios in military has greatly enhanced the ability of military equipments against jamming and interception and brought up a new austere challenge for communication countermeasures

    跳頻通信具有良好的抗干擾性,低截獲概率及組網能力,因此跳頻技術的一出現,便在軍事領域得到了極大的發展,採用跳頻技術的短波電臺在軍事通信中得到了廣泛應用,極大地提高了軍事裝備的抗截獲和抗干擾能力,向通信對抗提出了嚴峻的挑戰。
  14. This thesis researched the time synchronization method for 2d - ss system, and deeply discussed the bit error rate ( ber ) performance of multicarrier domain spread spectrum chip - level differential detection ( mc - ss - cldd ) in the presence of multi - user interference

    本論文從多載波擴頻通信系統出發,提出了廣義二維擴頻系統的同步演算法,並對多載波頻域擴頻碼片級差分檢測技術在多用戶情況下的系統性能進行了深入的研究。
  15. The wireless channel based on spread spectrum modulation can assure the digital video signal communication safe and withstanding the high noise disturbing condition

    而基於擴頻技術的無線通信通道,為視頻的傳輸提供了保密及抗干擾性能強等優點。
  16. A novel communication receiver which uses lapped transform ( lt ) incorporating modified median filter ( mmf ) algorithm is designed for narrow - band interference excision. the lt domain mmf algorithm takes full advantages of the direct sequence spread spectrum signal, as well as the characteristics of lt, performing the transform domain filtering twice. the first filtering locates the position of interference and mitigates most of them. the second filtering is performed in a small neighborhood of the located interference. so lt domain mmf algorithm can completely mitigate the interference without distorting the desired signal. simulation results demonstrate the improved ber performance and increased robustness of our receiver

    本文採用改進的重疊變換域中值濾波演算法進行變換域抗干擾處理.該演算法既考慮到直接序列擴頻信號的特點,同時又利用重疊變換的特性對變換域系數進行了二次濾波.該演算法節省處理時間,並且不需要有關干擾的先驗知識,系統性能不會隨干擾頻率變化而變化,因而是一種很穩健的處理方法
  17. Spread - spectrum secure communication based on hyperchaos system of cellular neural network

    基於細胞神經網路超混沌系統的擴頻保密通信
  18. 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。
  19. Then, based on the theory of discrete fourier transform, discrete cosine transform and discrete wavelet transform, two invisible image watermarking schemes in transform domain are proposed, one is circular symmetric spread spectrum digital image watermarking based on chaotic sequences, the other is the hybrid image watermarking based on wavelet decomposition and discrete cosine transform. finally, the good performance of the two algorithms is verified by some common image processing and attack experiments

    在分析了dft 、 dct 、 dwt的理論與演算法的基礎上,提出了兩種基於變換域的圖像隱形水印方案? ?基於混沌序列的圓對稱擴頻水印方案和基於小波分解和餘弦變換結合的水印方案,並通過一些常見的圖像處理及攻擊實驗驗證了這兩種演算法生成水印的性能。
  20. The parallel combinatorial spread spectrum provides high spectral efficiency and the data rate of the parallel combinatorial spread spectrum is higher than that of the direct sequence spread spectrum. this thesis studies on the mapping between data and spread sequence in the parallel combinatorial spread spectrum system and presents a mapping method based on the lexicographic order. the mapping method resolves the many to one mapping problem of the past method

    本文研究了并行組合擴頻中數據和擴頻序列之間的映射方法,指出了已有的一種不定方程求解演算法中存在的映射不唯一問題,應用組合數學中的相關理論,將映射問題轉化為廠組合問題,提出了基於字典順序的并行組合擴頻數據映射演算法,該演算法具有普遍性,解決了原有演算法中的多一映射問題。
分享友人