| 1. | A time - frequency domain method for carrier frequency estimation 2
提出了用时频理论来估计载波频率和位同步信息。 |
| 2. | Frequency domain method , however , takes an advantage in the aspect
而以传递函数矩阵为基础的频域法在这方面具有很大的优势。 |
| 3. | A time domain method of the simulating sar raw target signals is presented firstly , which can simulate accurately raw dates but burdens upper computational complexity . therefore , a frequency domain method with lower computational complexity is also proposed
因此,又给出了一种频域回波信号生成算法,该方法能够在满足一定条件下利用二维fft算法快速产生分布目标的回波信号,具有较高的计算效率。 |
| 4. | The used value of doppler centroid influence the imaging result very much , so it must be estimated precisely . the estimating methods contain time domain method and frequency domain method . time - frequency analysis method can be used to improve estimating precision
多普勒中心频率的取值对成像效果有很大影响，必须精确估计，估计方法有时域方法及频域方法，还可利用时频分析方法提高估计精度是。 |
| 5. | The other is the modern frequency domain method performed by rosenbrock . the design objective is the diagonal dominance , not the diagonalization , so it may avoid the limitation of the complete decoupling . it is an approximate decoupling method
其二是以rosenbrock为代表的现代频域法，其设计目标是被控对象的对角优势化而非对角化，从而可以在很大程度上避免全解耦方法的缺陷，这是一种近似解耦方法。 |
| 6. | The current control approaches are based on frequency domain methods such as pid control which assumes linear time invariant system dynamics . the advantages of these approaches are simplicity and ease of stability and robustness analysis . however , the decrease in performanc e and poor efficiency translates to additional payload and cannot meet the demand of current spacecraft control
当前飞行器主要的控制方法是基于近似时不变线性系统的频域分析法(如pid控制) ，这种方法的优点是简单且易于稳定性和鲁棒性分析，但它所达到的低性能和低效率却转化成了飞行器控制过程的附加载荷，还远不够满足当前飞行器控制的要求。 |
| 7. | These roof structures are generally in high turbulent regions , then wind loads become important to these structures . commonly , wind - induced response is analysed in frequency domain method . but the contributions of those high order models are omitted owe to the complexity of analyse themselves
分析结构风致响应时一般采用频域法，而频域法中采用常规的模态分析方法? ?振型截断法时，往往因为对高阶振型本身分析的复杂性而忽略了高阶振型对结构响应的影响，使得计算的结果缺乏合理性。 |
| 8. | ( 2 ) for linear systems with time - varying delays both in state and control , and subject to norm - bounded parameter uncertainties , the problems of robust stabilization and robust h control are studied and delay independent results are derived by constructing proper lyapunov function to deal with the time - delay , also by using riccati equations method and inequalities transformations to deal with the uncertainties . according to the transform function of the system , frequency domain method and time domain method are combined together to analyze the robust h control problem of the uncertain time - delay system
( 2 )研究了一类状态和控制同时具有时变时滞以及参数时变有界不确定性系统的时滞无关的鲁棒镇定及h控制问题，采用把时滞因素和不确定因素分开处理的思路，通过构造适当形式的lyapunov函数来处理时滞，采用不等式变换及riccati方程方法来处理不确定性，采用频域与时域相结合的方法根据系统的传递函数分析时滞不确定系统的鲁棒h控制问题。 |
