has an embedded unique cyclostationary signature, which can
be assigned as in [13] and detected with a cyclostationary
feature detector described earlier. The broadcast signal carries
information required to coordinate the cell’s operation, such as
the rendezvous channel or temporal spectrum allocations for
whitespace devices. 3) When another whitespace device with
no internet connectivity arrives in the coverage region of the
whitespace access point, it sweeps the whitespace bands to
detect the broadcast signal. If the broadcast signal is detected,
the device decodes it and reads the cell’s information. Then,
using the rendezvous channel it associates with the access point
and stays on the detected channel listening to the broadcast
signal, becoming a subordinate device. If another whitespace
device arrives, a similar procedure follows. 4) Whenever one of
the subordinate devices requires transmission to another local
device (or to the Internet), it requests (using the rendezvous
channel) whitespace operation. 5) The access point queries the
database and allocates a whitespace channel that meets the
demands of the requested transmission, indicating to both the
whitespace devices the centre frequency, assigned bandwidth,
spectrum availability determination period, and the peer device’s
MAC address for direct device-to-device transmission.
6) The information is embedded to the control channel and
both devices receiving the information reconfigure their radio
front-ends to operate on the specific centre frequency and start
the data transmission.