Spectrum access for Internet of things (IOT) applications including receiving information about expected use by a primary user of a spectrum band in a radio frequency spectrum. The spectrum band is classified into at least two working modes based on the expected use. The spectrum band is sensed to determine a current access pattern of the primary user. Based on the classifying and the sensing, one of the working modes is selected as a current working mode of the primary user. Transmissions are scheduled on the spectrum band using a current schedule that is responsive to the current working mode of the primary user. If the current working mode of the primary user changes, the sensing, selecting, scheduling, and determining whether the current working mode has changed are re-performed. Otherwise, the transmission scheduling and determining if the current working mode has changed are re-performed.