A high speed orthogonal dense wavelength division multiplexing DWDM signal generator includes a multi-peak continuous wave signal generator responsive to a light source, an optical filter for separating multi-peaks of lightwaves from the generator; and a polarization multiplexing stage responsive to the multi-peaks of lightwaves from the optical filter for providing a polarization multiplexing optical signal. The generator includes a cascaded phase modulator and intensity modulator driven by a repetitive frequency (I) to generate multiple spectral peaks, each peak being modulated by an optical modulator driven by a respective baud rate (f baud/s) electrical signal.