武汉理工FSK调制与解调系统设计实验

is one of the practical form of values. The so-called values refers to the objective things are of no value and the value of fundamental perspective. Different values, peoples behaviour, attitudes, ways are different. People-oriented focus on human value and reality, we need the broadest masses as values. Adhere to people-oriented values, is to make the economy more development, improve democracy, cultural prosperity, and live a happier; is deeply concerned that human development and human values, development of social and human development of rational unified, insisted in the material civilization, political civilization and spiritual civilization in the overall advancement of Socialist civilization to a higher level. Also want to see that persons value is not only meet your needs, also is to meet the needs of others and the community. Adhere to people-oriented, to strongly advocate every community member, serve others, beneficial to the community of people. The so-called Outlook, attitude is on the record, including who, how to create a record of achievements, how to evaluate performance, and so on. What values, what kind of Outlook. Adhere to people-oriented Outlook, is on the premise of respecting the interests and power of people, creating a popular, warm hearts, steady heart performance, creating serve for one officer, the benefit of achievements, and overall construction of well-off society and promoting the all-round development of peoples performance. Achievement evaluation in both economic accomplishments, take another look at the effectiveness of social progress; changes in both urban and rural change; both hard environment to strengthen and take another look at the soft environment improvement momentum of development at present, depending on the potential for sustainable development. Leave people to talk about values are worthless and leave people to talk about Outlook is not what the performance. 4. people responded to the starting point of the question, and replied to questions point. Man is the sum of social relationships. We cannot leave the chichuanyongdu, housing, tourism and entertainment, entertaining, and even certain political, economic, cultural and social environment, and so on. Due to human needs, all walks of life will come into being. People create for their survival, and continue enjoying the results of the construction. Colorful in the transformation of the people of the world, community vitality in the creation of man. Therefore, any work we do, the starting point is human, what are people. Us speed up development, the core of which is to meet the needs of people, including survival needs, emotional needs and self-actualization needs. It should be noted that people are not machines, not the slave of an object, not to be controlled. People have their own personality, has its own personality, has its own dignity. Person in need of care, you need to understand, need to meet. It is said that in the agricultural society, people plant; in industrial society, man is an animal; the information society, return实验课程名称：通信原理实验_实验项目名称移频键控FSK调制与解调系统设计实验实验成绩实 验 者专业班级组 别同 组 者实验日期一、实验目的、意义数字频率调制是数据通信中使用较早的一种通信方式，由于这种调制解调方式容易实现，抗噪声和抗衰减性能强，因此在中低速数据通信系统中得到较为广泛的应用。通过此综合实验，应达到：1进一步加深对数字调制中的移频键控FSK调制器与解调器工作原理及电路组成的理解与掌握。2学会综合地、系统地应用已学到的知识，对移频键控FSK调制与解调系统电路的设计与仿真方法，提高独立解决问题的能力。二、设计任务与要求 1.设计任务：构建并设计一个数字移频键控FSK传输系统，具体要求是：主载波频率：11800HZ载波1频率：2950HZ（四分频）载波2频率：1475HZ（八分频）数字基带信号NRZ：15位M序列，传输速率约为400波特。（32分频） 2.设计要求：FSK调制器可以采用数字门电路构成电子开关电路(或集成模拟开关)与采用集成模拟乘法器，利用键控法实现。FSK解调器可以采用非相干解调法或过零检测法实现。传输信道不考虑噪声干扰，采用直接传输。整个系统用EWB软件仿真完成。三、2FSK 调制与解调系统原理与电路组成1.方案论证(2FSK调制与解调系统原理的简要说明)1）FSK调制信号的产生实现数字频率调制的方法很多，总括起来有两类。直接调频法和移频键控法。注意到相邻两个振荡器波形的相位可能是连续的，也可能是不连续的，因此有相位连续的FSK及相位不连续的FSK之分。并分别记作CPFSK及DPFSK。实用电路中还可以借助于数字电路来实现移频键控，晶振输出的主载波，通过不同次数的分频(或倍频)器，可得到两种不同频率的载波，其相位也不完全相等。当数字基带信号g(t)为高电位时，与非门1关闭。与非门2打开，输出频率为f2的信号。当g(t)为低电位时与非门1打开，与非门2关闭，输出频率为f1的信号。这样，经过相加器相加后，就可输出2FSK信号。这种方法实现移频键控电路集成化程度高、体积小、可靠性高。图1频率键控调制器2.单元电路设计1）主载波振荡器电路设计主要提供2FSK的载波和信码的定时信号，可用集成电路（555）构成多谐振荡器，产生的振荡频率为11800Hz载波，要求输出频率可调。已知由（555）构成多谐振荡器的振荡频率为：则R1=3.6KR2=2.8K（可调）C=0.01uF图2 555 定时器接成的多谐振荡器2）M序列产生电路实际的数字基带信号是随机的，为了实验和测试的方便，一般都用M 序列产生器产生的伪随机序列来充当数字基带信号。本次设计采用三级线性移位寄存器（选用74LS74双D2片），形成长度为23-1=7位码长的伪随机码序列，码率约为400bit/s，如图3所示： 图3 M序列发生器电路图3）分频器将主载波按设计要求，一般用D触发器构成适当的分频电路，获得载频f1、f2和序列所需的时钟信号（电路设计方法参见实验四或其它有关资料）。8分频器4分频器4）调制器调制器可以采用数字门电路构成电子开关电路（或直接选用集成模拟开关）与采用集成模拟乘法器。这里使用与门和或门，图4 调制电路5）波形变换电路由于555产生的是正弦波，因此要有一个积分电路将其转化为正弦波，如图5 图5 波形变换电路6）非相干解调电路对于非相干检测法，其系统电路构成如图5.5所示。在了解与掌握了2FSK非相干检测法系统电路的基础上，进行自己的设计与实验。需要设计的单元电路有：图6 2FSK非相干解调电路原理图高通滤波器采用RC无源电路，构成三阶高通滤波器。已知2FSK的中心频率：,且滤波器的通带频率：，所以有：， 。则有C1=C2=C3=0.6uf R1=R2=R3=50低通滤波器低通滤波器选用一般RC滤波器电路，因信码速率为400波特，其电路元件参数：R=0.5K C=1uF电压比较器电压比较器用运算放大器构成迟滞比较器，目的是防止干扰，参考电压设定为0.22V。3.总体电路原理图与元件清单(1)总体电路原理图图6 总体电路原理图（2）元器件清单序号元器件名称型号规格数量备注1运算放大器22555定时器13D触发器74LS84固定电阻10K25固定电阻3.6k26固定电阻50017固定电阻5038可变电阻2.8K/50%19固定电容0.01uf110固定电容1uf111固定电容10uf112固定电容0.6uf313可变电感0.9mH/50%114二极管115门电路若干四、实验内容与测试数据1.FSK调制器的测量1）检测，调整多谐振荡器输出的载波信号测量点测量波形频率数备注P111800Hz主时钟2）调测分频器的分频比测量点测量波形频率数备注P1、P21474Hz8分频P1、P42590Hz4分频P3&P5 M序列3）M序列发生器产生的为随机码的检测测量点测量波形频率数备注时钟输入386HzM序列定时脉冲P3386HzM序列4）FSK调制输出信号的测量测量点测量波形频率数备注P51474Hz信码为“0”P52950Hz信码为“1”P3、P51474Hz/2950Hz信码为“M序列”2.FSK解调器的测量试验（非相干解调电路的测量）测量点测量波形备注P5、P6高通滤波器输出波形P7、P8检波器输出信号形及低通输出波形P3、P9电压比较器输出信号波形五、实验小结 通过这次实验，我对FSK调制解调系统有了更深刻的认识，仿真用的是 multisim软件,通过仿真来弥补实验未得到的结果，收益颇多。 Now, we are in a new historical stage of all-round construction of a well-off society. In perform duties, and carried out work of process in the, we to put people as a guide principles, and a test standard, efforts from masses most hope do of things do up, from masses most care of hot problem grabbed, from masses most not satisfaction of place modified up, not make nominal of formalism, not do grandstanding of cosmetic, to seeking of style, help masses share, is people benefit. (C) the investee people is not only an idea, it is a job requirement. Philosophy through to the people-oriented thought in the work of the Office, must be clear work objectives. Party Office in the city this year remains: Advanced civil strife, local brand. The County (City) Party Committee offices and units directly under the Office to hold high the banner of first to excellence, people-oriented requirements, strengthen the construction and management of the Office towards the work a higher level. Investee 1. political participation based on conspiracy to adhere to people-oriented, will be around to promote coordinationDevelopment events, great searchings. The 16 session of the partys scientific Outlook on development, is the new Central collective leadership to the development of connotation, development essentials, further deepen the essence of development and innovation, is our partys ruling idea a leap. At present, establishing and implementing the scientific concept of development has become the partys important work. As the Office of party Committee, working party should service center, initiative to claim leadership of the decision, the current focus is to focus on promoting comprehensive, coordinated and sustainable development with more suggestions, do more research, summarized the typical. One is drafted to raise the level of your presentation. Your presentation is the main Office of products, is the basic carrier staff service, is important to measure service levels. The quality of your presentation, mainly depends on how much we drafted a document recognized by the leadership, how many are listening to the people in favour of the report, how many paid dividends in the practical work. Improve presentation drafting level, requirements we accurate grasp l