Design Of High Efficiency Front-end Power Amplifier Module With Gain Compensation Function

With the rapid development of modern wireless communication, the application of corresponding product has distributed in many fields. For example, the mobile telephone is the most successful application in modern society. For both IC and module of power amplifier (PA), as the power dissipation part of radio frequency (RF) system, the pursuit of high efficiency has always been the popular research point. The conventional method of efficiency upgrading is to reduce the conduction angle. With the PA operation mode changing from Class A, Class AB to Class B, Class C, the circuits efficiency enhance based on the sacrifice of linearity and gain. When the conduction angle is zero, the theoretic efficiency is100%, but the output power is zero. Thus, merely reducing the conduction angle of RF power device is necessary, but not sufficient to obtain a useful improvement in efficiency. Given attention to both power and efficiency, the operation mode of Class D, Class E and Class F also have important application value in modern industry. The core method is to reduce the overlapped area of current and voltage on device and to control the impedance on harmonic frequency.Firstly, the article analyzed the basic mathematic principle and design method of high efficiency power amplifier. Secondly, the design process of "high efficiency front end RF power amplifier module with gain compensation function" has been introduced. The key design detail, such as match network, combining network, stability, power detection, has been discussed in this research. Finally, the testing results of this PA module have been presented.The article mainly focused on the following part:a. The system scheme of RF transmitting chain with gain compensation function has been designed.b. The Class F power amplifier module with power combination scheme has been designed and debugged.c. The other important RF module such as drive amplifier module, digital-controlled amplifier module, power detection module have been designed and debuggedd. The RF transmitting chain has been debugged and tested.