356 research outputs found
UMTS radio-over-fiber pico-cell interconnection employing uncooled DFB lasers for multi-mode fibre modulation bandwidth enhancement
This paper analyzes experimentally the use of distributed feedback lasers (DFB) in order to increase modulation bandwidth in multimode fibres, enabling 3 km bidirectional radio-over-multimode fibre UMTS transmission in a frequency-division duplexing (FDD) configuration
Optical Supersymmetry in the Time Domain
Originally emerged within the context of string and quantum field theory, and
later fruitfully extrapolated to photonics, the algebraic transformations of
quantum-mechanical supersymmetry were conceived in the space realm. Here, we
introduce a paradigm shift, demonstrating that Maxwell's equations also possess
an underlying supersymmetry in the time domain. As a result, we obtain a simple
analytic relation between the scattering coefficients of a large variety of
time-varying optical systems and uncover a wide new class of reflectionless,
three dimensional, all-dielectric, isotropic, omnidirectional,
polarization-independent, non-complex media. Temporal supersymmetry is also
shown to arise in dispersive media supporting temporal bound states, which
allows engineering their momentum spectra and dispersive properties. These
unprecedented features define a promising design platform for free-space and
integrated photonics, enabling the creation of a number of novel reconfigurable
reflectionless devices, such as frequency-selective, polarization-independent
and omnidirectional invisible materials, compact frequency-independent phase
shifters, broadband isolators, and versatile pulse-shape transformers
UWB wireless coexistence by fibre-based photonic ADC interference monitoring
The interference monitoring of UWB wireless picocell clusters through an in-house fibre installation is proposed and evaluated in a proof-of-concept experiment. UWB clusters enable range extension of UWB technology providing Gbit/s communications in home or office buildings. Coexistence of a large number of UWB clusters with other wireless services is guaranteed by a photonic analog-to-digital converter employing the in-house optical fiber installation
Performance of MB-OFDM UWB and WiMAX IEEE 802.16e converged radio-over-fiber in PON
Experimental results about the performance of converged radio-over- fiber transmission including multiband- OFDM UWB and WiMAX 802.16e wireless over a passive optical network are reported in this paper. The experimental study indicates that UWB and WiMAX converged transmission is feasible over the proposed distribution set-up employing a single wavelength. However, the results indicate that there is an EVM penalty of 3.2 dB for a UWB 10 km SSMF transmission in presence of WiMAX wireless
Joint distribution of polarization-multiplexed UWB and WiMAX radio in PON
In this paper, the feasibility of the joint distribution of ultra-wideband (UWB) and WIMAX wireless using polarization multiplexing as a coexistence technique is proposed and experimentally demonstrated within the framework of passive optical networks (PON). Four single- and orthogonal-polarization multiplexing schemes are studied targeting to reduce the mutual interference when UWB and WiMAX are distributed jointly through standard single-mode fiber (SSMF) without transmission impairments compensation techniques and amplification. Experimental results indicate successful transmission up to 25 km, in SSMF exceeding the range in typical PON deployments. The radio link penalty introduced by optical transmission is also investigated in this paper
VCSEL-based, CWDM - PON systems using reflective technology for bi-directional multi-play service provision
Orthogonal frequency division multiplexing based on radio-overfiber schemes allows the direct use of multiple, native format wireless platforms. In combination with standard baseband provision such as Gigabit Ethernet, this provides access to a wide range of services without requiring specialized end-user equipment. However, such signals have a high laser power-bandwidth requirement which may not be a good fit to the domestic environment. Here we explore the use of low-power optical components in customer premises which interface with an intermediate optical network node. Two solutions in the context of SSMF over a CWDM optical network are described, based on either reflective or direct modulation. EVMs of better than 35 dB were achieved. Š2012 Optical Society of America
Performance analysis of multiple radio-access provision in a multicore-fibre optical fronthaul
[EN] In this work we report a comprehensive experimental study targeting the dimensioning of the next-generation multicore-fibre (MCF) optical fronthaul employing space-division multiplexing (SDM). This fronthaul is capable of simultaneous provision of multiple radio-access technologies (multi-RATs) with advanced multi-antenna MIMO capabilities per RAT. The different parameters required for fronthaul dimensioning are evaluated considering state-of-the-art 4G LTE-Advanced altogether other legacy wireless standards in operation nowadays. In particular, the modulation characteristics, the antenna quality requirements (in terms of EVM, phase error or rho) and the signal-to-noise ratio (SNR) thresholds are evaluated employing fully-standard cellular signals transmitted on a multicore fibre (MCF) fronthaul. The study includes bi-directional signal transmission and multi-antenna MIMO multiplexing. The MCF optical fronthaul is evaluated with a multiplexed transmission of 2G, 3G, 3.9G and 4G MIMO signals in radio-over-multicore-fibre (RoMCF) employing a commercially available four-core MCF. The SNR requirements at the transmitter antenna are obtained for each cellular signal considering GSM, EDGE, EGPRS2-A, cdma2000 1xEV-DO, UMTS HSPA+ and LTE-Advanced standards. LTE-Advanced singleantenna and two-antenna systems implementing 2 x 2 MIMO transmission can be accomplished with SNR levels over 25 dB. In the case of LTE-Advanced 4 x 4 MIMO multiplexing over four cores of MCF media, 32 dB SNR is needed to achieve almost four times provided bitrate per user.This research was supported in part by Spain National Plan MINECO/FEDER UE TEC2015-70858-C2-1-R XCORE and GVA AICO/2018/324 NXTIC projects. The work of M. Morant is supported by Spain Juan de la Cierva, Spain IJCI-2016-27578 grant and Fundacion BBVA Leonardo 2018 HYPERCONN project.Morant, M.; Llorente, R. (2019). Performance analysis of multiple radio-access provision in a multicore-fibre optical fronthaul. Optics Communications. 436:161-167. https://doi.org/10.1016/j.optcom.2018.11.036S16116743
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