An analysis of Near Travelling Wave-Semiconductor Optical Amplifier (NTW-SOA) is presented to investigate its inline detector performance. The detected voltage is evaluated for various lengths and positions of the electrode along the active region of the device, for input optical power levels ranging from-25 dBm to +5 dBm. Under optimum conditions, the differential detection scheme shows an improvement of 3.7 dB, 4 dB for 40 mA, 50 mA bias currents respectively at-10 dBm input power, when compared with the best differential inline detection scheme reported in the literature. Further an improvement of 4.3 dB and 5.5 dB are obtained, when compared with the single electrode detection model under similar operating conditions. © 2010 PACS.