Narrow-Band OFDM Mode for WLAN

Systems and techniques relating to wireless communications are described. A described system includes circuitry configured to generate, in accordance with a clock signal, a first baseband signal for transmission over a wireless channel, one or more first preamble symbols of the first baseband signal are based on a pre-determined preamble sequence when a first clock frequency is used in the clock signal. The described system includes circuitry configured to generate, in accordance with the clock signal, a second baseband signal for transmission over the wireless channel, one or more second preamble symbols of the second baseband signal are based on the pre-determined preamble sequence, the one or more second preamble symbols have a longer duration than the one or more first preamble symbols when a second clock frequency is used in the clock signal. The second clock frequency is lower than the first clock frequency and is used to extend a wireless communication range of the wireless channel.