Carrier-less amplitude and phase (CAP) modulation can be a good candidate for short range optical communications for considerable computational complexity reduction and simple system structure. In this paper, a detailed investigation on the digital filters in CAP modulation system is presented. An adaptive equalizer based on cascaded multimodulus algorithm (CMMA) is used for the demodulation at the receiver. The impact of digital filter taps on system performance is investigated through comprehensive simulations and a 10 Gb/s CAP16 modulation system is demonstrated experimentally. The BER performance for different length of fiber link is measured. Compared with back-to-back (BTB) transmissions, 2 dB and 3.5 dB receiver power penalty are observed at BER of 10-3 for 20 km and 40 km fiber link respectively. It clearly demonstrates the feasibility of the CAP16 modulation for the short range transmission systems.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics