A method of transmitting data may include converting a stream of serial data bits into a set of parallel quadrature amplitude modulation (QAM) symbols. The method may additionally include applying a partial discrete Fourier transform-spread technique to transform a block of low-frequency subcarriers into a single-carrier QAM signal. The single-carrier QAM signal may bear information of a first subset of QAM symbols from the set of parallel QAM symbols. The method may additionally include transforming one or more remaining QAM symbols to form one or more subcarriers. Each of the one or more subcarriers may bear information of a corresponding QAM symbol from the one or more remaining QAM symbols. The method may additionally include generating a hybrid signal that includes the single-carrier QAM signal and the one or more subcarriers. The method may additionally include transmitting the hybrid signal.