A divided spectrum balanced detection technique for intensity noisereduction in SAC OCDMA systems

In this paper we propose a simple divided spectrum balanced detection (DSBD) for spectral amplitudecoding (SAC) optical code division multiple access (OCDMA) systems. SAC OCDMA systems are limited byphase induced intensity noise (PIIN), which is a signal dependent source of noise. Our proposed techniquereduces the PIIN by dividing the spectrum of the signal into two or more, and detecting each spectrumby a different photodiode. The DSBD scheme reduces the detected optical power at photodetection, thusresulting in a higher mitigation of the PIIN. Theoretical results show that DSBD demonstrate noticeableimprovement over traditional balanced detection technique, for example an up to 33% increase in thenumber of active users can be achieved, and at least 1 × 10−3b/s Hz increase in the spectral efficiency isobtained. However, the SDBD is more complex and append more constrains on system components