| 1. | Spread spectrum modulation ssm 扩频调制 |
| 2. | In chapter 4 , the spread spectrum modulation sequence performance is discussed on the base of the multiple address selected ability and secret communication 在第四章中,在基于多址选择能力和保密通信的基础上对扩频调制序列性能进行了讨论。 |
| 3. | The wireless channel based on spread spectrum modulation can assure the digital video signal communication safe and withstanding the high noise disturbing condition 而基于扩频技术的无线通信信道,为视频的传输提供了保密及抗干扰性能强等优点。 |
| 4. | A kind of secure communication system scheme is presented , which utilizes vss synchronizing controller to demodulate . amplitude masking modulation and spread spectrum modulation are considered to validate feasibility of the presented scheme 在此基础上,提出了一种基于变结构混沌同步的保密通信系统模型,该模型把一个混沌系统作为加密调制器,其变结构同步控制系统作为解调器。 |
| 5. | The second part studies the characteristics of cdma2000 1x reverse link , and implements a softcore design of the cdma20001x rtl soc with hdl ( hardwire desciptionin language ) verilog in accordance with the is - 2000 specifications . the model include the softcore of a spread spectrum modulation and a simple 8 - bit processor . as the same time simulate all the parts of the soc softcore with software modesim ,本文的第二部分认真的研究了cdma20001x的反向链路的特点,设计反向链路的扩频调制片上系统方案。用硬件语言verilog设计cdma20001x的扩频调制片上系统的ip软核。其中包括扩频调制部分和一个8位的cpu设计。 |
| 6. | An asymmetric digital watermarking algorithm based on dwt is presented in this paper . the watermark was embedded into the middle _ high coefficients based on spread spectrum modulation scheme , and the intensity of embedding could be accommodated adaptively , so the digital watermarking system has good perceptual invisibility and robustness 该算法利用私钥把水印嵌入到小波分解后的中高频系数中,提高了水印系统的不可视性,水印嵌入过程中可以自适应的调节嵌入强度,同时引入了扩频的概念,增强了水印系统的鲁棒性。 |
| 7. | This paper presented a general systematic view , application and current development of the power line carrier transmission technology , and clearly compared some existing power line carrier communication chip with each other . then the authors analyze the channel " s characters of low voltage power line , and formed an abstract carrier channel model . using this as its basis , a new kind of transmission technology is designed that adopted transmission technology combining the spread spectrum modulation with channel coding , which can solve the problems above mentioned to a certain degree , and need not pay for high cost 文章不仅全面地介绍了电力线载波通讯技术的特点、应用及其发展状况,还对目前的电力线载波通讯芯片进行了比较;并通过对低压电网信道特性的分析和研究,抽象出其载波信道模型,在此基础上,提出了将扩频调制和信道编码相结合的传输技术用于低压电力线载波通信,这可以在很大程度上解决电力线的干扰问题,且不必付出高昂的代价。 |
| 8. | Simulation results demonstrate theoretical derivation is correct and both sequences can be used in communication . based on the presented ds / sfh communication scheme , and employing msk as fh spread spectrum modulation , the performance is studied n the presence of partial band multitone jamming and additive white gaussian noise ( awgn ) 根据所提出的混合ds sfh扩频通信系统方案,采用msk相干调制,在假设直接序列扩频后信号带宽等于跳频间隔的情况下,推导了系统在部分频带多频干扰和加性白噪声下的误比特率公式。 |
| 9. | This chapter is a base of next chapter . mathematics theory and pseudo stochastic code theory for spread spectrum modulation sequence are introduced , and simulink experiment and analysis about correlation performance of the most common use spectrum modulation sequence are processed , these experiment contact to performance parameters of the spread spectrum sequence . the correlation performance and address quantity are compared between m sequence and gold sequence 本章是第五章的理论基础,介绍了扩频调制序列的数理基础和伪随机码理论,同时联系调制序列的性能指标对最常用的两种扩频调制序列的相关性能进行了仿真研究和分析讨论,比较了m序列和gold序列互相关特性和地址数。 |