摘要
数字电视发射机是采用OFDM调制方式,因此对发射机中功率放大器的效率会提出非常高的要求。针对OFDM信号的高峰均比(PAPR)特性,将Doherty功放引入前端功率放大器,介绍了Doherty功放的原理和基本结构,通过计算机仿真验证了这种功放电路在数字电视发射系统中的应用效果,设计了具体的实际电路,并进行测试,取得实际的结果。结果表明所设计的Doherty功放很好地解决了目前数字电视前端发射机存在的效率低的问题,具有很大的实用性。
Since the OFDM modulation is used in the digital TV transmitter, the efficiency of transmitter power amplifier is required critically. According the characteristic of peak to average power ratio （PAPR） of OFDM signal, Doherty amplifier is introduced into the front-end power amplifier. The principle and basic structure of Doherty amplifier is introduced. The application effects of the amplifier circuit in the digital television transmission system are verified through the computer simulation. The actual circuit was also designed and tested. The results show that the Doherty amplifier has solved the low efficiency problem existing in digital TV front-end transmitter and has high practicability.
出处
《现代电子技术》
2010年第23期187-188,191,共3页
Modern Electronics Technique
基金
2009年福建省自然科学基金重点资助项目(2009H0028):<宽带自适应线性射频功率放大器的研究>
