We propose and demonstrate for the first time a cost-effective and colorless wavelength-division-multiplexed passive optical network which can provide a full-duplex 155-Mb/s up/downstream data and broadcast signals on a single wavelength using light-injected optical sources and bidirectional transmission in a single fiber. The optical sources for downstream and upstream baseband data are Fabry-Perot laser diode (FPLD) at the central office and a reflective semiconductor optical amplifier (RSOA) at each optical network unit, respectively. The broadband light source (BLS) for the downstream is implemented by using mutually injected FPLDs. The transmission experiment shows that the error-free operation for baseband data and a high-quality broadcast signal with 3-dB CNR margin can be obtained.