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local oscillation 【物理學】本機振蕩。

local preacher

By using irm , heterodyne receiver with good image rejection and mmw - to - if once frequency conversion can be realized , which simplified receiver constitution prominently . the number of local oscillation ( lo ) sources is reduces and electromagnetic compatibility ( emc ) of mmw system is improved . also , the size , weight , power consume and cost of mmw receiver is reduced 采用毫米波鏡頻抑制混頻器,可在保證鏡頻抑制性能的前提下,采用1次變頻接收機,從而大大簡化接收構成,減少本振數量,改善毫米波系統電磁兼容性,減小接收機體積、重量、功耗,并降低成本。

With the established rf front - end system simulation platform , adding the digital modulated baseband signal , this paper simulated the multifold digital modulated signal ’ s transmission , such as 2ask , qpsk , and 16qam . then researches of power compression and phase noise of local oscillation influence the bit error ratio for different modulated system . the designing is satisfied multifold functions request with the high - powered and integrated broadband rf front - end 隨后在建立的寬帶射頻前端通用仿真平臺上,加入基帶數字調制信號,對多種數字調制格式的信號在該通用平臺上的傳輸作了研究,模擬了2ask 、 qpsk和16qam等調制格式信號的發射與接收,研究了功率壓縮和本振相位噪聲對不同調制的誤碼率影響,實現了滿足多種功能要求的寬帶高性能綜合射頻前端的設計。

Delay line oscillator is composed of broadband amprifer adjustable attenuator and saw sensor device . after output signal of delay line oscillator is smoothed , it mixes with 109mhz local oscillation signal . its differential frequency signal is smoothed by low - pass filter trimmed by shaping circuit and processed by digital processing circuit 延遲線振蕩器由寬帶放大器、可調衰減器和聲表面波質量傳感器件構成。延遲線振蕩器輸出信號經濾波后與109mhz的本機晶體振蕩器輸出信號相混頻,通過低通濾波取其差頻,并經整形后由數字信號處理電路處理。

Intermodulation suppression for fh ( frequency hopping ) receiver is designed by selecting the intermediate frequencies and changing group of filters , local oscillation ( lo ) frequency , bandwidth of lo frequency under the condition that receiver configuration , sensitivity , dynamic range , instantaneous bandwidth and precision of frequency measurement are fixed 摘要針對跳頻接收機的體制和靈敏度、動態范圍、瞬時工作帶寬、測頻精度等設計參數,通過改變預選器組成、本振頻率和本振帶寬,分析接收信道的中頻選取原則,以實現跳頻接收機的互調抑制設計。

The experimental result expresses that the frequency doubler - power amplifier sets of ka - band can supply good local oscillation source for “ millimeter - wave front - end of “ lmds “ “ . the model has the advantages of low cost , small size and high reliability 實驗結果表明,倍頻放大組件能夠為lmds毫米波前端提供很好的本振源,并且具有成本低、體積小、可靠性高等優點。

The authors also indicate that the local oscillation is worthy of consideration too 風應力異常的局地振蕩對elnino lanina現象的影響也不應忽視。