An apparatus for communication in a wireless communication network comprises a coder that encodes a set of data symbols to produce a set of coded symbols; a modulator that modulates the coded symbols onto a set of subcarrier frequencies to generate a time-domain signal comprising a sum of a set of modulated pulse waveforms; and a transmitter configured for transmitting the time-domain signal in the wireless communication network. The coder employs a matrix of spreading codes, wherein each column of the matrix multiplies a different one of the data symbols, which causes the modulator to produce a corresponding one of the set of modulated pulse waveforms. Each column of the matrix of spreading codes comprises a set of linearly increasing phases, which provides a time offset to the corresponding modulated pulse waveforms.