The ThinkRF R5500 Real-Time Spectrum Analyzer allows the end-users to load a customized calibration file to the unit in order to optimize the unit, to reduce unit-to-unit variation or to enhance parameters that are most important to the end-users' application. 

A calibration file is for mapping the reference levels against various radio settings and physical parameters, such as frequency,temperature, and insertion loss of the attenuator. 

This application note provides a step-by-step calibration procedure for the end-users to do such calibration.

View AppNote: How to Perform a Custom Calibration on a ThinkRF R5500