Simultaneous WDM and broadcast transmission using a single multiwavelength waveguide-grating-router laser

We have demonstrated a new technique for simultaneously transmitting multiple WDM channels and broad-band broadcast services using a single multiwavelength waveguide-grating-router laser. Four 150 Mb/s WDM channels, spaced by 1.6 nm, were formed by modulating four gain sections on an 8-wavelength waveguide-grating-router laser. A broadcast service, consisting of 79 MPEG video channels multiplexed into 16 QPSK subcarriers, was simultaneously added to each WDM carrier by modulating the laser´s common gain section. To eliminate degradations in video quality due to clipping distortion during baseband zeros, baseband extinction ratios for the four WDM channels were kept in the 55% to 58% range.