A network node, wireless device and various methods are provided. For example, a network node for operating in an unlicensed frequency band is provided. The network node includes processing circuitry configured to: modify at least one function of at least one carrier in a frequency band edge of the unlicensed frequency band where the frequency band edge being located, in a frequency domain, in a non-transmission portion of a spectrum mask that is configured to reduce leakage into an adjacent frequency band, and perform a communication function using the at least one carrier having the modified at least one function.