Abstract:
To serve large geographical area, there is need to drive antenna with high power. It necessitates the requirement of high power amplifier (PA) for delivering large RF output power. Alongside power added efficiency (PAE) and linearity should be optimized to meet the requirements of the high capacity and high quality services of next generation communication systems. RFPA capability is highly dependent on the transistor material quality. It is known that a high terminal voltage is required for achieving high output power from a transistor device. In this context, a device possessing large bandgap so that it can be operated at high terminal voltages is required. AlGaN/GaN HEMT technology is becoming an interesting candidate for the PA design as GaN is a wide band gap material. In addition, it can be operated at high operating frequency owing to its high saturation velocity. The efficient and cost effective RFPA design flow requires identification of optimal circuit configuration on computer aided design (CAD) tools prior to fabrication. This necessitates accurate transistor model to simulate its real time behavior. In the case of GaN HEMTs, modeling attains significant importance considering the device complexity and not a well-developed fabrication process. It is envisaged that the systematic modeling strategy can facilitate its fabrication process to a significant extent. This thesis presents the study and implementation of small-signal modeling technique and device capability based on measured data.
The final outcome is presented in the form of an equivalent electric circuit that can be represented as a device in CAD
