A system, method and apparatus are described for digitally synthesizing a signal for FM transmission. A complex variable frequency digital IF signal is generated for use by a digital modulator in transmission of a signal with an integrated circuit. In some examples, the integrated circuit includes various baseband processing blocks, an up-sampler, a summer, a numerically controlled oscillator (NCO) and a complex rotator, all arranged in cooperation with one another. The complex variable frequency digital IF signal can be used by a digital quadrature modulator for generation of the synthesized analog RF transmission signal, and optionally for use with an orthogonal frequency division multiplexing (OFDM) scheme.