Polarization-interleave-multiplexed discrete multi-tone modulation with direct detection utilizing MIMO equalization

Abstract

Discrete multi-tone (DMT) modulation is an attractive modulation format for short-reach applications to achieve the best use of available channel bandwidth and signal noise ratio (SNR). In order to realize polarization-multiplexed DMT modulation with direct detection, we derive an analytical transmission model for dual polarizations with intensity modulation and direct diction (IM-DD) in this paper. Based on the model, we propose a novel polarization-interleave-multiplexed DMT modulation with direct diction (PIM-DMT-DD) transmission system, where the polarization de-multiplexing can be achieved by using a simple multiple-input-multiple-output (MIMO) equalizer and the transmission performance is optimized over two distinct received polarization states to eliminate the singularity issue of MIMO demultiplexing algorithms. The feasibility and effectiveness of the proposed PIM-DMT-DD system are investigated via theoretical analyses and simulation studies.

Programmable disaggregated multi-dimensional S-BVT as an enabler for high capacity optical metro networks

“…In order to further improve system/network capacity while improving SE, polarization information can also be exploited [27,28]. Accordingly, different signals can be independently transmitted over orthogonal polarizations of the same optical wavelength.…”

“…Specifically, a time delay between the two polarization modes appears as they are transmitted at different propagation constants. Different techniques have been proposed in the literature to mitigate this effect and dynamically equalize the channel, which includes multiple input multiple output (MIMO) technique [28].…”

Meeting the future metro network challenges and requirements by adopting programmable S-BVT with direct-detection and PDM functionality

“…For instance, two OFDM signals can be multiplexed into orthogonal polarization states (polarization division multiplexing, PDM), enabling 50 % spectral saving and promoting resource dynamicity [9, 10,11].…”

“…Specifically, electrical solutions can relay on lin-45 ear and nonlinear equalization, which can be based on multiple-input multipleoutput (MIMO) processing, implemented with a polarization diversity receiver [3,10,11,15]. Additionally, polarization tracking algorithms can be also implemented in the digital domain to control the SOP of the received signal [16].…”

“…linear equalizer based on ZF has been implemented by setting half of the TS to 0, in order to create orthogonal symbols [11]. Hence, increased overhead is needed in comparison with independent equalization.…”