In embodiments, a wireless device, such as a Wi-Fi device, transmits communication signals on secondary channels within an operational bandwidth of a wireless network, concurrent with a transmission from another wireless device on a primary channel. The wireless device may detect that a first frequency band within an operating bandwidth of a wireless network is occupied by a first transmission transmitted by a second wireless device, and determine that a second, different frequency band within the operating bandwidth of the wireless network is not occupied. In response, the wireless device may transmit a second transmission occupying the second frequency band concurrent with the first transmission. The wireless device may set a duration of the second transmission based at least in part on a determination of whether the second wireless device is configured to assess the state of all frequency bands within the operating bandwidth before beginning a subsequent transmission.