A method for an Electronic Device, ED, in a wireless network, the method comprising: receiving, by the ED, an uplink grant message from a base station, the uplink grant message indicating a time-frequency resource allocated to the ED for uplink transmission in an unlicensed spectrum band; performing, by the ED, a first listen-before-talk, LBT, operation for the allocated time-frequency resource; if the first LBT operation fails, performing, by the ED, a second LBT operation within the allocated time-frequency resource; characterized in that in response to the second LBT operation succeeding, transmitting, by the ED, an uplink transmission within a remaining portion of the allocated time-frequency resource, the uplink transmission comprising: an activation signal to indicate a start of the uplink transmission; and uplink payload data, wherein the ED is allocated a subset of subcarriers of a component carrier, CC, bandwidth; the second LBT operation is a narrowband LBT operation that is based on energy measured on the allocated subset of subcarriers during one or more orthogonal frequency division multiplexing, OFDM, symbol intervals immediately preceding a start point within the allocated time-frequency resource, wherein a bandwidth of the narrowband LBT operation performed by the ED is narrower than a full channel bandwidth of the CC or bandwidth part in which an uplink resource is scheduled; and the transmitting of the uplink transmission comprises transmitting, by the ED, the uplink transmission on the allocated subset of subcarriers within the remaining portion of the allocated time-frequency resource. receiving, by the ED, an uplink grant message from a base station, the uplink grant message indicating a time-frequency resource allocated to the ED for uplink transmission in an unlicensed spectrum band; performing, by the ED, a first listen-before-talk, LBT, operation for the allocated time-frequency resource; if the first LBT operation fails, performing, by the ED, a second LBT operation within the allocated time-frequency resource; characterized in that in response to the second LBT operation succeeding, transmitting, by the ED, an uplink transmission within a remaining portion of the allocated time-frequency resource, the uplink transmission comprising: an activation signal to indicate a start of the uplink transmission; and uplink payload data, an activation signal to indicate a start of the uplink transmission; and uplink payload data, wherein the ED is allocated a subset of subcarriers of a component carrier, CC, bandwidth; the second LBT operation is a narrowband LBT operation that is based on energy measured on the allocated subset of subcarriers during one or more orthogonal frequency division multiplexing, OFDM, symbol intervals immediately preceding a start point within the allocated time-frequency resource, wherein a bandwidth of the narrowband LBT operation performed by the ED is narrower than a full channel bandwidth of the CC or bandwidth part in which an uplink resource is scheduled; and the transmitting of the uplink transmission comprises transmitting, by the ED, the uplink transmission on the allocated subset of subcarriers within the remaining portion of the allocated time-frequency resource.