基于DSP的短波通信系统设计（射频单元）

电子通信论文编号:TX079        论文字数:22168,页数:41

目录
摘要
ABSTRACT
1 绪论  1
1.1 研究和发展现状  1
1.2 射频及射频电路的概念  2
1.3 射频电路设计的对策  3
2 系统总体方案设计  7
2.1 射频发射器芯片原理与应用电路设计  7
2.1.1 概述  7
2.1.2 发射机的选取  11
2.1.3 主要性能指标  11
2.1.4 芯片封装与引脚  12
2.1.5 内部结构与工作原理  13
2.2 功率放大器的设计  16
2.2.1 功率放大器总述  16
2.2.2 功率放大器的工作方式  17
2.2.3 放大器的设计  19
3 影响射频电路性能的主要原因分析  21
3.1 信号的反射及阻抗匹配  21
3.2 射频部分电路设计的一些考虑  22
3.3 射频部分电路中频频率的确定  24
3.4 使用SMD  24
3.5 射频功放的线性和效率  25
3.6 射频功放的线性化技术  27
3.6.1 反馈  27
3.6.2 前馈  28
4 射频部分电路测试与结果  31
结束语  32

参考文献  33

摘要
在短波无线通信系统中，射频电路是在高频条件下进行工作的，因此，需要利用射频电路理论去理解射频电路的工作原理。在高频条件下的普通的设计电路，杂散电容和杂散电感对电路的影响很大。因此，我采用集成电路的设计方法来避免一些模拟电路的一些缺点。
迅速发展的射频集成电路，为从事无线数字音频，数字视频数据传输系统，无线遥控和遥测系统，无线数据采集系统，无线网络以及无线安全防范系统等设计，解决无线应用的平静提供最大的可能。
在整个短波无线通信系统的射频电路中包括，收发器，中频带通滤波器，基带解调滤波器，数据限幅电平，自动增益控制，基准振荡器，关闭功能，I/O接口电路等器件，主要为了实现短波无线通信的信号的输出以及对收到的信号作简单的处理，它相当于短波无线通信的前端设备。

关键词：射频电路，PCB设计，短波通信

ABSTRACT
In the system of shortwave air communication, the radio frequency circuit carries on work under the high-frequency condition. So, need to utilize the circuit theory of the radio frequency to understand the operation principle of circuit of the radio frequency. The ordinary design circuit under the high-frequency condition , stray electric capacity and impact on circuit of the stray inductance are very great. So, I adopt the integrated circuit design method to avoid some shortcomings of some simulation circuit.
The radio frequency integrated circuit developed rapidly,in order to be engaged in the wireless digital audio frequency, the data transmission system of digital video , wireless remote control and telemetering measurement system, wireless data collecting system, wireless network and wireless safe precaution system,etc. are designed, solve the wireless calmness that uses and offer the greatest possibility.
Include in the radio frequency circuit of the wireless communication system of the whole shortwave, the transceiver, the band-pass filter of intermediate frequency, baseband demodulation wave filter, the amplitude limiting level of the data, gain and control automatically, basic oscillator, close the function, such devices as I/O interface circuit ,etc., in order to realize the output of the signal of shortwave wireless communication and do simple processing to the signal that is received mainly, it is equivalent to the front equipment of shortwave wireless communication.

Key words： Radio frequency circuit ，PCB Design，shortwave communications