IM/DD WDM-PON Communication System Based on Optical Frequency Comb Generated in Silica Whispering Gallery Mode Resonator

Abstract

This article reports an implementation of a microsphere-based optical frequency comb (OFC) generator for substitution of individual laser arrays and simulates wavelength division multiplexed passive optical network (WDM-PON) based on this OFC generator. Our proposed generator is built based on silica microsphere, barely studied for fiber optical communication systems, and is a promising solution with photonic integration capability. Kerr OFC as a multiple light source containing more than 20 spectral carriers in the fundamental mode family in the C-band and beyond is demonstrated experimentally. Four of these OFC generator carriers with the highest peak power are studied in simulated 4-channel 393 GHz spaced WDM-PON. Additionally, we show this OFC as a source of optical carriers capable of providing data transmission over most utilized fiber types in modern optical communication systems, namely, singlemode fiber (SMF), non-zero dispersion-shifted fiber (NZ-DSF), and cut-off shifted fiber (CSF). We show through the simulations that error-free data transmission is possible, providing a total transmission capacity of 40 Gbit/s by using four OFC generated carriers.INDEX TERMS Optical frequency comb (OFC), silica microsphere, wavelength-division-multiplexing (WDM), passive optical network (PON).

Optical Frequency Combs Generated in Silica Microspheres in the Telecommunication C-, U-, and E-Bands

“…Samples of silica microresonators were made of standard ITU-T G.652.D telecommunication fiber Corning SMF28e using the technology described in detail in [24]. In brief, it is based on repeated melting of a thinned fiber end with a fiber splicer.…”

“…Note that the mode spacing 400 GHz = M × 100 GHz (M = 4) satisfies the ITU-T recommendation G.694.1 [36], which specifies the spectral grid for WDM systems. To excite WGMs in a microsphere, we used tapered fibers made of Corning SMF28e with gas burners [24,25,37].…”

“…Silica microresonators made of a standard optical fiber are suitable for application in the telecommunication range, since they can be pumped by narrow-linewidth C-band telecom lasers, and the corresponding experimental schemes are based on standard telecom components. Recently, we studied theoretically [23,24] and demonstrated experimentally [25] the implementation of wavelength division multiplexed-passive optical network (WDM-PON) in the C-band using an OFC generator based on a silica microsphere as a multiple light source. When several lasers (laser array) are replaced by a single OFC source, it improves the energy efficiency of the WDM fiber optical communication system, at the same time providing stable frequency spacing and strong phase relation between generated carriers (modes) [24][25][26].…”

“…Recently, we studied theoretically [23,24] and demonstrated experimentally [25] the implementation of wavelength division multiplexed-passive optical network (WDM-PON) in the C-band using an OFC generator based on a silica microsphere as a multiple light source. When several lasers (laser array) are replaced by a single OFC source, it improves the energy efficiency of the WDM fiber optical communication system, at the same time providing stable frequency spacing and strong phase relation between generated carriers (modes) [24][25][26]. Extending OFCs to the L-band is also a straightforward solution for WDM-PONs, when the use of the C-band is insufficient for satisfying the bandwidth demand.…”

POL-MUX System for Noncoherent Optical Networks

“…POL-MUX system was the subject of research mostly in the 1990s and plenty of research groups were interested in this topic. Although it allows doubling of bandwidth and brings many advantages in comparison with other known multiplexing techniques, due to difficult demultiplexing, it was no longer prospective for further development, and WDM systems played the main role in the field of optical networks for many years [8][9][10][11][12][13]. The renaissance came after 2000, when the group of Yao et al [5,6] engaged in research of POL-MUX systems using an all-optic scheme for polarization demultiplexing.…”