| 1. | A method of inserting spread spectrum watermarking into spread spectrum signal 扩频通信中扩频水印的嵌入方法 |
| 2. | The fpga and dsp architecture has been used in the digital correlator , by which the spread spectrum signal can be demodulated at the intermediate frequency 数字相关器采用fpga + dsp的结构设计,实现了扩频信号在中频的解扩解调。 |
| 3. | The purpose of fast capture is getting the return spread spectrum signals immediately , and then , track channels start tracking and demodulating the signals 快捕用于快速捕获转发返回的扩频信号,信号捕获后由跟踪通道进行跟踪解调。 |
| 4. | The hardware design includes pl2101 power line node , realization of narrow - band interferences in direct sequence spread spectrum signal using frequency - domain algorithm 其中硬件设计包括pl2101电力线节点、窄带干扰自适应抑制系统的实现。 |
| 5. | In order to supply the actual bpsk ds - ss signal to verify the algorithms , this dissertation present a design method of spread spectrum signal generator with adjustable muti - parameter in detail 为了给验证算法提供现实的bpsk调制的直接序列扩频信号,本文详细介绍了一种多参数可调的扩频信号源的设计方案。 |
| 6. | Wide doppler range . varied code length , varied code rate , which have more difficulties . little acquisition time and high acquisition probability are required during the capturing process of spread spectrum signals 对高动态、高码率、低信噪比、大多普勒及变化的码长和码率的扩频信号的快捕是本文的难点。 |
| 7. | For communication signals , we detect if there exist spread spectrum signals such as direct sequence spread spectrum ( dsss ) or frequency - hopped ( fh ) signals and estimate their parameters if the dsss or fh signals exist 其次,对通信信号,检测是否有扩频信号存在并估计扩频参数;如果是非扩频的一般调制信号,则识别其调制模式。 |
| 8. | In the text , direct sequence spread spectrum signal ( dsss signal ) is the main object , and some nonlinear methods based on chaotic theory , used in the prediction of signal and detection of signal is studied 本文以保密通信中广泛使用的直接序列扩展频谱信号( dsss信号)为主要对象,研究了一些基于混沌理论的非线性的方法在信号预测和信号检测中的应用。 |
| 9. | Several methods of sequence spread spectrum signals direction have been developed , such as energy detection , correlation detection , cepstrum detection , cyclic spectral , higher order cumulant detection , etc . these methods developed from the research of detection and estimation for ds signals 直扩通信信号检测的研究已发展出许多方法,如能量法、相关法、倒谱法、周期谱法及高阶谱法等。 |
| 10. | The square detection can picks up the carrier frequencies , which is simple and has great performance . but this method can ’ t recognize the signal as spread spectrum signal . the spectral correlation detection method can estimates the chip rate of signal ’ s pn sequence 然后,针对异步的cdma信号,采用延迟相乘的方法检测用户数目,同时估计出各用户信号的幅值和相位;该方法的缺点是各用户信号必须有一定的相差,同时用户数不能太多。 |