| 1. | As any other adaptive system , the following three steps are essential to our aofdm : estimating channel , choosing the right modulation parameters and signaling the chosen parameters 和任何自适应系统一样,此系统包括信道估计,调制参数选择,以及信令三个主要部分。 |
| 2. | According to transcendent knowledge , this algorithm classifies modulation systems by computing instantaneous frequency and instantaneous bandwidth of signal and regarding them as modulation parameters 该算法凭借先验知识,通过计算信号的瞬时频率和瞬时带宽,并以此作为制式识别参数来判断信号的调制类型。 |
| 3. | How to choose the modulation parameter is the main concern of chap 4 . supposing that channel estimation is complete , a closed form relation between modulation switching levels and target ber is first derived 首先在信道估计完全正确的假设下,推导出了调制方式切换门限与目标误码率在即时误码率及平均误码率约束下的关系表达式。 |
| 4. | Modulation format is one of the most important characteristics used to distinguish communication signals . knowing the modulation format and modulation parameters of a communication signal is the first step of correct demodulation 调制方式是区分不同性质通信信号的一个重要特征,而要截获通信信号的信息内容,必须知道信号的调制方式和调制参数。 |
| 5. | The method can measure the following parameters , ( pulse attitude ) pa , ( pulse width ) pw , ( time of approach ) toa , snr , ( radio frequency ) rf , pulse envelope characteristic parameters and intra - pulse modulation parameters with a high precision and a high discrimination 该算法能够分析雷达信号的脉冲脉幅、脉宽、到达时间、信噪比、载频、脉冲包络特征参数和脉内调制特征参数。 |
| 6. | Given a received communication signal , the objective of modulation recognition is to decide the modulation format and estimate the modulation parameters of the communication signal without any priori knowledge about the signal information content 给定一段接收的通信信号,调制识别的目的就是在未知调制信息内容的前提下,判断出通信信号的调制方式,并估计出相应的调制参数。 |
| 7. | Some modulation parameters , such as the carrier frequency and the symbol rate , can be estimated prior to the recognition of modulation types . such other parameters as the modulation index , the modulation frequency deviation , and the signal broadband can be further estimated after recognition 部分调制参数如载波频率、符号速率在识别之前获得,在识别完成之后可以进一步估计调制指数、调制频偏、信号带宽等其余参数。 |
| 8. | The numerical results of the dispersion relation show some nonlinear effects : for a fixed geometry of a waveguid , beam parameters and plasma density , the increment of the modulation parameter may lead to a slight increment of the operating frequency , however , as the modulation parameter increases further , saturation may occur and the dispersion relations are hard to be separated , it is due to the overmodulation of the microwave power , this phenomenon itself belongs to the nonlinear effects 对于一定的波导、电子注参量和等离子体密度值,等离子体调制系数的增加,使工作频率略微升高。但是,随着等离子体调制系数的进一步增加,色散曲线变得彼此之间不可分辨,可以认为是等离子体的过调制导致了栅的饱和。这一现象是非线性的,可见,等离子体栅和调制场中文摘要是非线性关系,等离子体栅是非线性j 。 |
| 9. | 3 . in order to show the fact that the - licrowave modulates the background plasma density and the density grating influences the propagation of the microwave in return , the dispersion relation of the dielectric cerenkov maser filled with plasma grating is derived when the modulation parameter is varied 三、为了反映等离子体被微波场调制从而形成密度周期性分布的等离子体栅,反过来影响电磁波的传播这一物理事实,在调制系数变化的情况下,从等离子体栅的等效模型出发,推导了等离子体栅填充的介质cerenkov脉塞的色散方程。 |