A method of operation by a radio node configured for operation in a wireless communication network, the method comprising performing a load-based Listen-Before-Talk, LBT, procedure by: setting a Clear Channel Assessment, CCA, budget as a function of monitored congestion on a carrier of the wireless communication network, wherein the carrier resides within a radio spectrum shared by the wireless communication network and another wireless communication network and is organized timewise into successive subframes, each subframe containing a defined number of symbol times, wherein the CCA budget comprises a designated number of contiguous symbol times within each subframe; and executing an extended CCA procedure by: performing CCA procedures repeatedly over as many subframes as are needed to reach a counted number of CCA procedures equal to a count value, based on performing CCA procedures only within the CCA budget of each such subframe, and by counting only successful CCA procedures; and beginning a data transmission in the subframe in which the counted number of CCA procedures reaches the count value, wherein beginning the data transmission in the subframe in which the counted number of CCA procedures reaches the count value comprises initiating the data transmission without first transmitting a channel-capture signal if the count value is reached coincident with one of one or more designated symbol times constituting a transmit start time. performing a load-based Listen-Before-Talk, LBT, procedure by: setting a Clear Channel Assessment, CCA, budget as a function of monitored congestion on a carrier of the wireless communication network, wherein the carrier resides within a radio spectrum shared by the wireless communication network and another wireless communication network and is organized timewise into successive subframes, each subframe containing a defined number of symbol times, wherein the CCA budget comprises a designated number of contiguous symbol times within each subframe; and executing an extended CCA procedure by: performing CCA procedures repeatedly over as many subframes as are needed to reach a counted number of CCA procedures equal to a count value, based on performing CCA procedures only within the CCA budget of each such subframe, and by counting only successful CCA procedures; and beginning a data transmission in the subframe in which the counted number of CCA procedures reaches the count value, wherein beginning the data transmission in the subframe in which the counted number of CCA procedures reaches the count value comprises initiating the data transmission without first transmitting a channel-capture signal if the count value is reached coincident with one of one or more designated symbol times constituting a transmit start time. performing CCA procedures repeatedly over as many subframes as are needed to reach a counted number of CCA procedures equal to a count value, based on performing CCA procedures only within the CCA budget of each such subframe, and by counting only successful CCA procedures; and beginning a data transmission in the subframe in which the counted number of CCA procedures reaches the count value, wherein beginning the data transmission in the subframe in which the counted number of CCA procedures reaches the count value comprises initiating the data transmission without first transmitting a channel-capture signal if the count value is reached coincident with one of one or more designated symbol times constituting a transmit start time.