Secondary use of the satellite spectrum by a terrestrial system is studied in this paper, focusing on broadcasting satellite services. Both spectrum sensing based access and database based access are discussed. Link budget analysis is used to define operational limits for spectrum sensing and transmission power control when the primary system is a Digital Video Broadcasting - Satellite services to Handheld devices (DVB-SH) system. The results show that cognitive radio techniques should be applied with caution in satellite bands. The energy detection method does not support well spectrum sharing in the studied band. Rather the sensing should be based on the feature detection or matched filter detection.