Compensation technique to improve the reliability of SSPA for space applications

A great design challenge for Solid State Power Amplifier (SSPA) designer for space applications is to maintain the optimum, stable & reliable operation under large temperature varying environment of spacecraft. It requires a precise temperature compensation technique to make various parameters like Gain, output power, quiescent current etc. independent of temperature. In absence of such technique it becomes difficult to maintain the device channel temperature of the active device, the most critical parameter, within the specified limit and hence affects the reliability of the system. The paper presents a detailed implementation of the drain current compensation circuit to make the device quiescent current independent of temperature variation and thereby improving the reliability of the space sub-system.