With the increasing importance and demand for wireless communications, there is a spectrum crunch and there is no easy way to meet this increasing demand. Spectrum monitoring is a key enabler for understanding how the spectrum is currently used and identifying opportunities for spectrum sharing. This paper focuses on analysis of a large volume of complex spectrum measurements in the public safety band and involves modeling spectrum sensors, public safety domain knowledge and events involving public safety. The information models developed can be used to create labels for the complex spectrum data and facilitate the analysis of the data needed for spectrum sharing.