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Ke WANG Ampalavanapillai NIRMALATHAS Christina LIM Efstratios SKAFIDAS
In this paper, we propose a high-speed full-duplex optical wireless communication system using a single channel imaging receiver for personal area network applications. This receiver is composed of an imaging lens, a small sensitive-area photodiode, and a 2-aixs actuator and it can reject most of the background light. Compared with the previously proposed system with single wide field-of-view (FOV) non-imaging receiver, the coverage area at 12.5 Gb/s is extended by > 20%. Furthermore, since the rough location information of the user is available in our proposed system, instead of searching for the focused light spot over a large area on the focal plane of the lens, only a small possible area needs to be scanned. In addition, by pre-setting a proper comparison threshold when searching for the focused light spot, the time needed for searching can be further reduced. Proof-of-concept experiments have been carried out and the results show that with this partial searching algorithm and pre-set threshold, better performance is achieved.
Kensuke IKEDA Christina LIM Ampalavanapillai NIRMALATHAS Chathurika RANAWEERA
Communication networks for wide-scale distributed energy resources (DERs) including photovoltaics (PVs), wind, storage and battery systems and electric vehicles (EVs) will be indispensable in future power grids. In this paper, we compare optical fronthaul networks using existing optical ground wires (OPGWs) for centralized radio access network (C-RAN) architecture to realize cost effective wireless communication network expansion including low population area. We investigate the applicability of optical data transport technologies of physical layer split (PLS), analog radio-on-fiber (ARoF), and common public radio interface (CPRI). The deployment costs of them are comparatively analyzed. It was shown that physical layer split and analog radio-on-fiber with subcarrier multiplexing (SCM) result in lower cost than other technologies.
Christina LIM Ampalavanapillai NIRMALATHAS Dalma NOVAK Rodney WATERHOUSE
We investigate the capacity limitations of a WDM ring fiber-radio backbone incorporating wavelength interleaving where each base station drives a sectorized antenna interface. We also investigate the issues related to the merging of such networks with standard WDM infrastructures. The investigations show that re-allocating the interleaved WDM channels to fit within a 100 GHz block enables the millimeter-wave (mm-wave) fiber-radio system with sectorized antenna interfaces to integrate easily with WDM systems. The performance of a variety of channel allocations for the merged fiber-radio network is examined and simulation studies of the transmission of multiple channels are carried out. The overall network capacity of the merged mm-wave fiber-radio network is improved with the proposed channel allocation schemes.
Benoît J. GOUHIER Ka-Lun LEE Ampalavanapillai NIRMALATHAS Christina LIM Efstratios SKAFIDAS
In this paper, we present a new electro-optic (EO) probing system based on heterodyne detection. The use of a recirculating frequency shifter allows to expand the bandwidth of the system far beyond what is attainable with a conventional heterodyne EO set-up. The performance for the frequencies up to 50GHz is analysed to forecast the viability of the system up to the THz range.
Dong-Soo LEE Yang Jing WEN Je Soo KO Man Seop LEE Ampalavanapillai NIRMALATHAS
We investigate the impact of electrical band-limitation on the transmission performance of both carrier suppressed return-to-zero (CSRZ) and CSRZ differential phase shift keying (CSRZ-DPSK) format for high spectral efficiency DWDM systems. Results show that electrical band-limitation improves signal spectral compactness, leading to reduced linear crosstalk and improved tolerance against chromatic dispersion in optical fiber link without causing any degradation to fiber nonlinearity tolerance. In addition, it is shown that the electrical band-limitation is more efficient to CSRZ-DPSK signal than CSRZ signal in reducing signal degradation caused by linear crosstalk and fiber chromatic dispersion.