| 1. | The tracking scheme can track the variance of the mimo channel and further reduce system cost . finally , we introduce an mqam sm - ofdm adaptive power and bits allo - cation scheme
以此为基础的信道跟踪方案能进一步减少系统开销，而且能很好地跟踪mimo信道的变化。 |
| 2. | The performance of our parameter estimation algorithm applied to mask and mqam signals with known level order are preliminarily investigated through computer simulation . 3
把基于累量分析的信号参数估计算法用于已知调制类型的mask 、 mqam信号，通过大量的计算机仿真，初步考察了算法的性能。 |
| 3. | Moreover , new close - form ber expressions of mqam and mpsk in nakagami - / ? ? fading channel are derived , which include the known analytical results as a special case
本文还导出了nakagami - m衰落信道下mqam和mpsk调制方式新的误比特率表达式，该表达式可以使现有文献的分析结果西南交通大学博士研究生学位论文第v页成为其特例。 |
| 4. | Also , new expression of ser of mqam in frequency selective fading channel with rake combining is obtained , and throughput performance adaptive mqam with rake receiver in multipath rayleigh fading channel is analyzed
本文还得到了mqam在频率选择性衰落信道中采用rake合并新的误码率表达式，并对采用rake接收的自适应mqam在多径瑞利衰落信道中吞吐量性能进行分析。 |
| 5. | The new algorithms for classification of mpsk , mask and mqam signals using cumulant invariants are proposed in gaussian noise and ideal communication channel environment . the new classification features are blind to unknown snr and reference phase
提出了在高斯噪声和理想信道环境下，基于高阶累量不变量特征的mpsk 、 mask和mqam信号调制分类算法，新特征对信噪比和未知的参考相位参数是盲的。 |
| 6. | Based on the analysis of invariant features in cumulant domain of communication signals , the classification of communication signals with mpsk , mask and mqam modulation formats is investigated this dissertation . the main works can be summarized as follows : 1
本文在前人工作的基础上，通过对信号累量域不变量特征的分析，深入研究了mpsk 、 mask和mqam数字通信信号的调制识别问题，主要工作可概括如下： 1 |
| 7. | After comparing their own feature , this paper points out a good future of hfc . hfc network uses high performance , high rate and multi - level digital modulation schemes . the emphasis of the thesis lies in the research of the advanced digital modulation - mpsk and mqam
本文深入研究了hfc系统中采用的高性能、高速多进制的数字调制解调技术? ? mpsk和mqam的实现原理，并探讨了它们的功率利用率和频带利用率两个重要指标。 |
| 8. | At the same time , analysis of effects of gaussian distributed and uniform distributed feedback error of the channel fading behavior on throughput performance of adaptive mqam reveals that the obvious throughput loss shall be observed as far as the error exceeds certain limit
同时，高斯分布和均匀分布的信道衰落信息反馈误差对自适应mqam吞吐量性能影响的研究表明，当误差超过一定程度时，自适应系统吞吐量性能明显下降。 |
| 9. | Take the hoc based blind modulation detection algorithm as an example , the relationship between the blind modulation detection algorithm and synchronization is investigated . an unproved detection algorithm robust to frequency offset is proposed which solves the problem caused by the error in carrier synchronization . how to synchronize a received signal with unknown modulation type is studied and a blind algorithm to estimate symbol timing of the signals with unknown modulation type is presented
研究了载波同步和码元定时同步与调制方式盲检测算法的关系；以自适应单载波中高阶累积量调制方式盲检测算法为例，对于载波同步误差引起的频偏问题，提出一种基于频偏稳健的mdpsk信号调制方式盲检测算法；对于未知调制方式信号的定时同步问题，提出一种盲定时估计算法，该算法可以估计mdpsk和mqam信号的定时同步信息，实现数字信号的同步分类；提出了一种基于调制方式盲检测的自适应接收机结构，把调制方式盲检测，信噪比估计和同步解调联合起来进行，实现调制方式随信道质量而自适应变化的信号的正确接收。 |
| 10. | Fpga and dvb standard are introduced firstly , dvb - c standard and composition of its system are analyzed completely , development of modulator structure and dvb - c digital modulator composition are presented , more over , analysis of respective modular are given . then , principle of dvb - c digital modulator system are presented , they are error control technique 、 mqam 、 nyquist rule and root raised cosine filter 、 window design method for fir filter 、 multi - rate signal processing ( integer interpolating , conversion of fractional sampling , equal conversion of net structure , polyphase structure for filter , poly - phase structure for interpolator , multi - stage implementation of samplying conversion ) 、 distrubited algorithm 、 cic filter 、 dds 、 cordic algorithm
接着,专门利用一个章节阐述了dvb - c前端调制系统原理,他们了差错控制技术、多进制调制( mqam ) 、 nyquist准则与平方根升余弦滤波器、有限冲击响应滤波器的窗函数设计法、多抽样率信号处理包括(整数倍内插原理、分数倍抽样率转换、网络结构的等效结构、滤波器的多相表示、内插器的多相表示、抽样率转换的多级实现) 、分布式算法、 cic滤波器、直接数字频率合成( dds ) 、 cordic算法。 |
