AbstractOriginal results are presented for an optical wireless system employing dicode pulse position modulation (DiPPM) and a PIN‐BJT receiver. When operating at λ = 0.85 μm and a bit rate of 10 Mb/s, a sensitivity of −51 dBm (Pe = 10−9) is achieved, which represents a 10.3‐dB improvement, as compared to an equivalent PCM system. The work also demonstrates that DiPPM achieves comparable sensitivities to those of the digital PPM format, but at significantly reduced line rates, thus making it a credible candidate for mobile devices using optical wireless technology. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 273–277, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20794