A broadcast base station , comprising: at least one radio transmitter ; one or more processors coupled to the at least one radio transmitter ; wherein the broadcast base station is configured to: wirelessly broadcast audio and video data to a plurality of broadcast receiver devices using a particular frequency band; discontinue broadcasting in the particular frequency band during a scheduled time interval, to enable the one or more cellular base stations to perform bi-directional packet-switched wireless data communications using the particular frequency band; determine its spectrum usage based on current programming and communicate its ability to relinquish spectrum to one or more cellular base stations ; transmit control signaling to the plurality of broadcast receiver devices during the scheduled time interval, the control signaling including synchronization information to allow the plurality of broadcast receiver devices to remain connected during the scheduled time interval with the broadcast base station and to receive broadcast content, at the end of the scheduled time interval, in active intervals by superimposing cellular synchronization and cell configuration parameters with broadcast frame parameters; and align frames of broadcast data with a boundary of frames transmitted by the one or more cellular base stations . at least one radio transmitter ; one or more processors coupled to the at least one radio transmitter ; wherein the broadcast base station is configured to: wirelessly broadcast audio and video data to a plurality of broadcast receiver devices using a particular frequency band; discontinue broadcasting in the particular frequency band during a scheduled time interval, to enable the one or more cellular base stations to perform bi-directional packet-switched wireless data communications using the particular frequency band; determine its spectrum usage based on current programming and communicate its ability to relinquish spectrum to one or more cellular base stations ; transmit control signaling to the plurality of broadcast receiver devices during the scheduled time interval, the control signaling including synchronization information to allow the plurality of broadcast receiver devices to remain connected during the scheduled time interval with the broadcast base station and to receive broadcast content, at the end of the scheduled time interval, in active intervals by superimposing cellular synchronization and cell configuration parameters with broadcast frame parameters; and align frames of broadcast data with a boundary of frames transmitted by the one or more cellular base stations . wirelessly broadcast audio and video data to a plurality of broadcast receiver devices using a particular frequency band; discontinue broadcasting in the particular frequency band during a scheduled time interval, to enable the one or more cellular base stations to perform bi-directional packet-switched wireless data communications using the particular frequency band; determine its spectrum usage based on current programming and communicate its ability to relinquish spectrum to one or more cellular base stations ; transmit control signaling to the plurality of broadcast receiver devices during the scheduled time interval, the control signaling including synchronization information to allow the plurality of broadcast receiver devices to remain connected during the scheduled time interval with the broadcast base station and to receive broadcast content, at the end of the scheduled time interval, in active intervals by superimposing cellular synchronization and cell configuration parameters with broadcast frame parameters; and align frames of broadcast data with a boundary of frames transmitted by the one or more cellular base stations . <EOS>