Search

We experimentally demonstrate a 100 G ADC-MLSE-based 4-lanes NRZ direct detection transceiver. The DSP engine enables the use of low cost 10 G optoelectronics and supports 40 km metro transmission suitable for both ASE limited and point-to-point applications. The fully implemented mixed signal ASIC is based on standard 65 nm CMOS process.

We propose a novel architecture of an optical code division multiple access, implemented by the method of self-heterodyne filtering (SHF). Theoretical and experimental results are introduced. The SHF method allows multiple channel access by the use of low-cost passive optical components, and standard on-off keying modulation.

We propose coherent detection with one sample/symbol. Maximum-likelihood sequence estimation (MLSE) is used to compensate for intersymbol interference introduced by antialiasing filtering. The 100 000-ps/nm chromatic dispersion and 100-ps differential group delay are compensated with 1.5-dB penalty. Blind MLSE equalization is proposed.

Blind channel estimation is critical for digital signal processing (DSP) compensation of optical fiber communications links. The overall channel consists of deterministic distortions such as chromatic dispersion, as well as random and time varying distortions including polarization mode dispersion and timing jitter. It is critical to obtain robust acquisition and tracking methods for estimating these distortions effects, which, in turn, can be compensated by means of DSP such as Maximum Likelihood Sequence Estimation (MLSE). Here, a novel blind estimation algorithm is developed, accompanied by inclusive mathematical modeling, and followed by extensive set of real time experiments that verify quantitatively its performance and convergence. The developed blind channel estimation is used as the basis of an MLSE receiver. The entire scheme is fully implemented in a 65 nm CMOS Application Specific Integrated Circuit (ASIC). Experimental measurements and results are presented, including Bit Error Rate (BER) measurements, which demonstrate the successful data recovery by the MLSE ASIC under various channel conditions and distances.

We propose coherent detection with one sample per symbol. MLSE is used to compensate for ISI introduced by anti-aliasing filtering. 100,000 ps/nm CD and 100 ps DGD are fully compensated with only 1.5 dB penalty.