Design Of RF Broadband High Gain Drive Amplifier

The development of radio frequency communication has put forward more stringent index requirements for the transceiver system.With the commercialization of5 G technology in the communication field,the research on 5G chips is of great significance for the huge chip market of 5G frequency bands.Among them,the power amplifier,as the most critical part of the transceiver system,determines the transmission efficiency of the entire module,and at the same time determines the overall power consumption to a large extent.In view of this,this article uses a 2?m gallium arsenide HBT process to design a high-gain drive amplifier with a frequency band of 50MHz-6GHz for the 5G RF1 frequency band.The frequency band not only covers the 5G RF1 frequency band,but can also be used in other communication systems such as TD-LTE and GSM.GaAs HBT devices stand out because of their superior performance and relatively low cost,and are widely used in the design of power devices.The gallium arsenide HBT structure embodies good linearity and high power capacity in the design,but there is also a certain risk of thermal stability.When high current is injected,the self-heating effect of the device itself will cause current collapse.Aiming at the non-linear problem caused by the thermal effect,a new adaptive compensation circuit structure is proposed based on the addition of ballast resistors.This structure can effectively improve the DC point drift caused by temperature rise through negative feedback;by adding in the path Appropriate impedance structure and negative feedback improve the stability of the circuit structure;an ESD protection circuit is designed to avoid circuit breakdown.By simulating the schematic diagram and layout of the drive amplifier in ADS,all the indexes are finally reached through continuous optimization.Finally,the actual measurement results show that: the gain of the chip at low frequency reaches more than 20 d B;the P1 d B point is close to 20 d Bm;OIP3 reaches35 d Bm.The full-band input and output standing wave is obviously better than-10 d B,and the noise performance is good.The chip operates stably in high and low temperature environments.