数字调制解调技术大学毕业论文英文文献翻译及原文.docx

1、数字调制解调技术大学毕业论文英文文献翻译及原文 毕 业 设 计（论文）外 文 文 献 翻 译文献、资料中文题目：数字调制解调技术文献、资料英文题目：文献、资料来源：文献、资料发表（出版）日期：院 （部）： 专 业： 班 级： 姓 名： 学 号： 指导教师： 翻译日期： 2017.02.14英文文献Technology of digital modulation and demodulation plays a important role in digital communication system, the combination of digital communication tech

2、nology and FPGA is a certainly trend . With the development of software radio, the requirement for technology of modulation and demodulation is higher and higher. This paper starts with studying digital modulation and demodulation theory at first, and analyses basic principle of three kinds of impor

3、tant modulation and demodulation way ( FSK, MSK, GMSK ).The Rohde &Schwarz SME03, Signal Generator, provides AM modulation and External FSK digital modulation required for the development and testing of digital mobile radio receivers.The application of PWM in digital modulation and demodulation for

4、analog communication signals in several modulation modes Research results prove that the design of digital IF modulator and demodulator of Software Radio appeases the capability and requirement of Software Radio.A transfusion speed monitor system is designed based on infrared technology with modulat

5、ion and demodulation.Its the combination of modulator and demodulator.Time synchronization that is key technology of digital demodulation is cc allied by software.The paper provides the design of hardware of digital IF modulator and demodulator of Software Radio which includes Digital Signal Process

6、or、Micro Control Unit and AD/DA convertor etc.Digital Down/Up Converter(DDC/DUC), modulation and demodulation are discussed in the dissertation as some essencial parts of SDR platform. Two Way Automatic Communication System(TWACS) is a new valuable communication technology for distribution networks,

7、which has special of modulation and demodulation. In this paper, we study the OFDM technology based on 802.16a, realize the baseband modulation and demodulation by using TMS320C6201, and optimize the software module. The paper introduces the principle of QPSK modulation and demodulation, the circuit

8、 are also be realized based on FPGA.With the improvement of the technology, especially in the fields such as computer technology , data coding and compress , digital modulation and VLSI, the world electronic information industry enter into the digital era. First, the features of fax communication an

9、d the mode of modulation and demodulation are described.In automatic classification of digital modulation signal,computing envelope variance after difference has important meaning to distinguish PSK and FSK signal.The science and technology of space flight.The effect on modulation and demodulation o

10、f QPSK via carrier phase noise can not be ignored, and it is difficult to analyze.Digitalmodulationerror parameters, such as error vector magnitude EVM, is important in test and measurement of information system. This paper introduces the technology research progress in the metrology of digitalmodul

11、ationerror parameters. First, we point out the basic problems existing in the field, which is about traceability and parameter range of calibration, and describe the relevant research, such as the thinking and technology of the RF waveform metrology. Then, we highlight the research progress of our t

12、eam: 1). The metrology method and system for digitaldemodulationerror parameter based on CW combination, which fits BPSK, QPSK, 8PSK, 16QAM, 64QAMmodulation: this method can achieve traceability and error setting ability in a wide range, when standard EvmRms is 1.585%, the expanded uncertainty (k=2)

13、 is 0.009%. 2). The metrology method and system for digitaldemodulationerror parameter based on analogAMor PM. 3). The metrology method and system for digitaldemodulationerror parameter based on IQ gain imbalance and phase imbalance. 4). The metrology method and system for digitaldemodulationerror p

14、arameter based on analog PM in the aspect of GMSK and FSKmodulation. 5). The metrology method and system for digitaldemodulationerror parameter based on Baseband waveform design. Based on these methods, our proposal are given as follows: first, establish public metrology standard for digitalmodulati

15、onerror parameters; second, develop a new type of instrument vector signal analyzer calibrator.In this paper, we propose a novel method of chaoticmodulationbased on the combination of Chaotic Pulse PositionModulation(CPPM) and Chaotic Pulse WidthModulation(CPWM). This combination looks very promisin

16、g for the improvement of information privacy in chaos-based digital communications. In the CPPM+CPWM method, each pulse is a chaotic symbol which carries binary information of two bits corresponding to its position and width, where the position is determined by the interval between rising edge of th

17、e current pulse compared to the previous one and the width is determined by the duration between the rising edge and the falling edge of the same pulse. This offers the increase of bit rate, bandwidth efficiency and privacy in comparison with the method of CPPM. The schemes ofModulationandDemodulati

18、on(MoDem) of CPPM+CPWM are proposed, designed and analyzed that based on the conventional schemes of CPPM. The numerical simulation in time domain of the system of CPPM+CPWM MoDem is implemented in Matlab/Simulink.It gives a summary of theoretical and practical studies on the properties of pulse-pha

19、semodulation, developed mainly in 1943. The properties of pulse-phasemodulationare studied by means of Fourier transformations. Although some approximations are introduced, the calculations lead to the following definite conclusions: (1) Pulse-phasemodulationintroduces no amplitude distortion except

20、 at sub-multiples of the recurrent frequency. (2) The harmonic distortion, if any, is negligible and this method ofmodulationcan be used for high-quality broadcasting. (3) Pulse-phasemodulationis subject to a special type of distortion called ?cross-distortion,? produced by side bands of the recurre

21、nt frequency appearing in the signal bandwidth. Curves of the approximate amount of this type of distortion are given, and it is shown that, in practical multi-channel systems, this distortion is negligible, provided that the recurrent pulse frequency is at least double the highest signal frequency

22、to be transmitted, and preferably equal to, or greater than, three times this frequency. This study is followed by considerations on the signal/noise ratio in pulse-phasemodulation. Pulse-phasemodulationis compared with amplitudemodulationand a formula, giving the improvement in the signal/noise rat

23、io due to pulse-phasemodulation, is established by very simple considerations. It is shown that this ratio improves as the frequency bandwidth used in pulse-phasemodulation. It is shown how an improvement of 3 db in signal/noise ratio can be obtained by suppressing the noise on the synchronizing pul

24、se, and a practical circuit developed and applied in 1943 by the author is described. Finally, a typical example of pulse technique is given. In practical circuits the modulator and demodulator pulses are not perfectly shaped, because of the departure from linearity due to finite time-constants. Thi

25、s introduces harmonic distortion. It is shown how this distortion can be practically elimi- nated by designing circuits so that the time constant is equal atmodulationanddemodulation.It present a novel technique for digital datamodulationanddemodulationcalled triangularmodulation(TM). Themodulationt

26、echnique was developed primarily to maximize the amount of data sent over a limited bandwidth channel while still maintaining very good noise rejection and signal distortion performance. Themodulationtechnique involves breaking digital data into a series of parallel words. Each word is then represen

27、ted by one half period of a triangular waveform whose slope is proportional to the value of the parallel word it represents. Thedemodulationtechnique for this uniquely defined waveform involves first digitizing the waveform at a higher constant sampling rate. A linear regression algorithm using the

28、method of least squares is then used to compute the slope of the digitized waveform to a very high precision. This process is repeated for each rising and falling edge of the triangular modulated waveform. All encoded data is extracted by precise slope computation since each slope uniquely defines t

29、he encoded data word it represents. The ability of thedemodulationalgorithm to compute the exact slope of the modulated waveform determines how many bits can be represented by the modulated waveform. Transmission channel bandwidth limitations determine the allowable range of slopes used. Several sim

30、ulations are performed to provide a sample of how themodulationmethod will perform in various real world environments. The paper also discusses several application areas where themodulationtechnique will provide superior results over othermodulationmethods.The theory of constant envelope orthogonal

31、frequency division multiplexing (CE-OFDM) is analyzed in this paper, along with the introduction of the implementation method of CE-OFDM technique. Besides, themodulationanddemodulationprocess is simulated and analyzed. And the results indicate that CE-OFDM conducts phasemodulationon the basis of OF

32、DMmodulation. Thus, FFT/IFFT is implemented in the transmitting and receiving terminals. Furthermore, the method of equalization applied in thedemodulationprocess can optimize system performance. And also, CE-OFDM solves the problem of high peak-to-average power ratio (PAPR) in OFDM, reducing PAPR to 0Db.High efficientmodulationtechnology is a hot research topic. UNBmodulation, for its good performance, is paid to more attention. First, the article introduces EBPSKmodulationscheme as UNBmodulationmethod, gives its time and frequency domain ch