.1.5 Mhz, ~ 30mhz Broadband High Linearity Amplifier Research And Design,

Because the short-wave communication can Work with simple equipment,easy to work with netwrok,and have a strong anti-destructive characteristic.It is widely used to transmit telegraph,telephone,data and static images,and occupy an important position in military telecommunications.Now the short-wave communication become more and more importantin in defense and military.With the development of short-wave communication technology, Linear modulation technology get more and more applications,and the linearity requirements of the transmitting and receiving system are also increased.HF communication use the frquency band between 1.5MHz-30MHz,As the Frequency band is so wide,the Second and Third-order component of signal are still in frquency band,using filters or other means can not filter them out. Therefore,as the main components of the transmitting and receiving device,the linearity of the amplifier largely determine the linearity of the communication system.This paper conduct Research and analysis on several practical amplifier linearization technique at home and abroad.Use the negative feedback circuit technology and the Balancing circuit technology,design and implement a full-band high linearity broadband amplifier that work in 1.5MHz-30MHz.Experimental results show that the Second-order intercept point of this amplifiers achieve to 72dBm,and the Third-order intercept point achieve to 39dBm.At present,the general third-order intercept point of domestic high frequency narrow-band linear amplifier is about 25dBm.As The same short-wave band amplifier,the Second-order intercept point achieve to 64dBm,the Third-order intercept point achieve to 30dBm.In this paper,the designed amplifier achieves better linearity compared to them.