高波道帶寬 的英文怎麼說
中文拼音 [gāobōdàodàikuān]
高波道帶寬
英文
luminance channel bandwidth-
A patch antenna with air holes in the substrate has been designed. the finite - difference time - domain ( fdtd ) method together with the perfectly matched layer ( pml ) boundary treatment has been used to study the performance of the antenna. it is shown that the surface waves are significiently suppressed, the frequency bandwidth is improved, the sidelobe levels are reduced and consequently the gain in the forward direction is improved by 14 db ( about 4 db higher than the value reported previously )
設計了一種基底鉆周期圓孔結構的電磁（光子）晶體貼片天線，用fdtd方法並結合pml吸收邊界條件對該天線進行了研究，結果表明本文所設計的基底鉆孔型電磁晶體貼片天線取得了多方面的性能改善，與普通天線相比，基底中的表面波受到很大抑制，天線的帶寬增加，遠場方向圖上天線的旁瓣和背瓣被明顯削弱，向前輻射的增益由原來的12db增加到26db ，增加了14db ，比文獻上報道的gonzalo等人的研究結果提高了4db 。The millimeter wave diplexers used in the ka - band satellite communications are investigated. these diplexers are of high working frequency, narrow passband and high selectivity, which demands the channel filters good performance
所研究的毫米波雙工器工作頻率高（接近40ghz ） ，收發通道帶寬窄、接收頻率和發射頻率間隔很小。Frequency - domain equalization. at the same time discusses some key problems in ofdm : high ratio of peak - to - average power of output signals, problem of synchronization, channel estimation, adaptive bit, power and subcarrier allocation. emphasize on channel estimation, and present a new algorithm which can filtering more interpolation errors and noise. for the sake of improve the performance of resist narrowband noise and make efficient use of the spectrum apply malvar wavelet division
同時就ofdm系統中的一些關鍵問題如峰值平均功率比（ papr ）太高，同步問題，通道估計，通道、比特與功率必須動態分配進行了研究，著重研究了通道估計問題並提出一種改進的方法，能濾除更多的噪聲分量和插值誤差，提高系統的性能；為了提高抗窄帶噪聲的性能和提高通道利用率，用malvar小波變換實現了不等帶寬分配。The project is to develop the 100mhz wideband digital storage oscilloscope ( wdso ) ， typical performance character : input signal - 3db bandwidth is 100mhz, real time sampling frequency is 20msa / s, equivalent sampling frequency is 10gsa / s, resolution is 8bits, dual signal channel, and delicacy is 5mv 5v div per channel ， time sweep velocity is 2. 5ns - - 5s div 。 so the project is provided with higher performance - to - price ratio, stronger competitive capacity in market and widest applied foreground at the area of wdso
本次課題的具體目標是實現100mhz帶寬的數字存儲示波器正樣機的研製，具體主要性能指標達到最高實時采樣率20msa / s 、等效采樣率10gsa / s 、被觀測信號3db模擬帶寬達100mhz 、采樣數字解析度8bit ；雙通道，幅值靈敏度： 5mv 5v div ，掃速2 . 5ns - - 5s div 。該方案具有較高的性價比，較強的市場競爭力和廣闊的應用前景。With the characteristics of large ambient noise, very narrow bandwidth, low carrier frequency, great propagation latency and time - space - frequency variant multipath effect ( mpe ), the stochastic ocean channel has demonstrated the greatest complexity and difficulty for underwater acoustic wireless communications. among them multipath effect ( mpe ) is the most difficult obstacle that results in signal fading and inter - symbol interference ( isi )
但是噪聲高、帶寬窄、載波頻率低、傳輸時延大、多途徑效應隨時間?空間?頻率變化等通道特性都會給有效、可靠的水聲通信帶來很大的麻煩，其中多途徑效應是最主要的困擾因素，它會導致信號幅度衰落和碼間干擾。分享友人