The results of the testing prove that the system compare with dsss takes great advantages over others on the aspects of the rate of transmitting data , its stabilization and its possibility of expanding 测试结果表明，与直序扩频系统相比， ofdm系统在数据传输速率、稳定性和可扩展性等方面具有十分明显的优势。
In the spread spectrum communication system , the synchronization of receiver ' s persedo - noise ( pn ) code to the transmitter ' s pn code is such an important part that the whole system ca n ' t work at all without it 在整个扩频系统中，接收端对发端扩频码的捕获和同步，是一项决定整个系统成败的至关重要的技术。
The emphases of this thesis are to implement the ss baseband communication system and to achieve behavior simulation and post - place & route simulation respectively on the platform of ise 4 本论文工作的重点是在ise4开发平台上具体实现这个扩频系统，并对系统中的每个模块和整个系统进行相应的功能仿真和时序时延仿真。
The pn sequence used by a ds - ss direct affects the performance of system . the pn sequence selected is crux of the ds - ss system . the discovery of chaotic dynamic system broad the way of study of pn sequence 而扩频系统所使用的扩频序列的性能直接影响到系统的性能，因此选用的扩频序列成为扩频通信系统的关键所在。
In additive white gaussian noise ( awgn ) channel , we introduce a method for synchronization of symbol timing and frequency for two - dimensional spread spectrum system without prior knowledge of spread spectrum matrix 摘要针对加性白高斯噪声信道，考虑未知二维扩频矩阵的条件下，提出了一种二维扩频系统的时频同步方法。
Chapter one introduces the characteristics of the ss communication system and the development related . to ss asic chip at present in the world . it also introduces the outline and the research idea of the thesis 论文的第一章介绍了扩频系统的特点以及相关扩频芯片的国内外发展现状，并介绍了本论文的研究思路和内容。
And what we do in this paper is to put forward an effective algorithm to estimate the sub - chip multi - path component of spread - spectrum positioning system with space - modulation and put it into practice 为此,本文针对时空调制扩频定位系统给出一种有效的码片内多径估计的算法,并用gps扩频系统的多径信号进行多径估计验证。
In chapter two we describe an adaptive array system model and the algorithm we used in this thesis , then introduce the principle of spread spectrum system and dynamic simulation tool system view in brief 第二章首先介绍了自适应阵列的系统模型及本文研究所采用的自适应算法，然后简单介绍了扩频系统的原理和动态实时仿真系统systemview 。
However in the practice spread spectrum communication system , the phase of the received signal is likely to be uncertain because of the instability of transmitter and receiver ' s clock , transmission delay and multi - path 而在实际的扩频系统中，由于收、发机时钟不稳定、电波传输时延、多径效应等原因造成接收信号中扩频序列相位不确定。
A special structure of coherent receiver is proposed which combine the advantages of the parallel and serial structure . the design of m - ary spread spectrum system is proved in the system of ( 32 , 5 ) which is small in scale 本文把提出的一些新的设计思路应用于多进制扩频系统（ 32 ， 5 ） ，通过该系统的设计和实现，证实了其可行性和可靠性。
