A method of mitigating start-of-packet interference in a millimetre waveband wireless mesh communications network which comprises a first plurality of network node devices each having a transceiver unit which includes a beamforming antenna device, and a second plurality of millimetre waveband wireless communications links each of which interconnects a respective pair of the transceiver units of the network node devices, the method comprising: allocating respective baseband centre frequencies to pairs of transceivers of the network node devices, which baseband centre frequencies are for use with respective communications links of the network, each such allocated baseband centre frequency being offset from at least one other allocated baseband centre frequency by a respective predetermined offset amount; and at a first transceiver of a selected pair of transceivers, encoding a data packet using an encoding signal having the baseband centre frequency allocated to the selected pair of transceivers, to generate an encoded signal.