ArticlePDF Available

All Optical Ultra-Wideband Signal Generation and Transmission Using Mode-locked laser Incorporated With Add-drop Microring Resonator (MRR)

Authors:
Reza Soltanian
Reza Soltanian
IS Amiri
IS Amiri
IS Amiri
  • This person is not on ResearchGate, or hasn't claimed this research yet.
S. E. Alavi at Universiti Teknologi Malaysia
S. E. Alavi
H. Ahmad at University of Malaya
H. Ahmad
Download full-text PDF
Read full-text
Download citation

Abstract

The novel technique for generating the robust, ultra-wideband (UWB) signal in optical domain using mode-locked laser incorporated with an add-drop microring resonator (MRR) filter is presented. In order to down conversion of UWB signal to RF domain two wavelengths range 1553.72 and 1553.92 nm which are 24.65 GHz apart from each other are used. These wavelengths were generated based on a single longitudinal mode (SLM) dual-wavelength fiber laser in a laser ring cavity. The upper wavelength of the generated dual-wavelength laser is modulated with the UWB spectrum using optical carrier suppression (OCS) scheme and the lower wavelength is kept unmodulated. After beating the modulated and unmodulated wavelength by launching into the photodiode, the 24 GHz UWB signal can be generated to be applied to UWB over Fiber (UWBoF) technology. The error vector magnitude (EVM) for the signal transmission was calculated and the EVM below 10% is achieved for 25Km optical and 20 m wireless links.
Content uploaded by Iraj Sadegh Amiri
Author content
All content in this area was uploaded by Iraj Sadegh Amiri on Jul 31, 2017
Content may be subject to copyright.
7/31/2017 All optical ultra-wideband signal generation and transmission using mode-locked laser incorporated with add-drop microring resonator - IOPscie…
http://iopscience.iop.org/article/10.1088/1612-2011/12/6/065105/pdf 1/3
LETTER
All optical ultra-wideband signal generation and
transmission using mode-locked laser incorporated
with add-drop microring resonator
M R K Soltanian , I S Amiri , S E Alavi and H Ahmad
Published 26 May 2015 • © 2015 Astro Ltd
Laser Physics Letters, Volume 12, Number 6
Abstract
This site uses cookies. By continuing to use this site you agree to our use of cookies. To find out
more, see our Privacy and Cookies policy.
1 1 2 1
isafiz@yahoo.com
ehsanalavi59@gmail.com
Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia
UTM MIMOS CoE in Telecommunication Technology, Faculty of Electrical Engineering, Universiti
Teknologi Malaysia, 81310 UTM Johor Bahru, Malaysia
Received 16 April 2015
Accepted 28 April 2015
Published 26 May 2015
M R K Soltanian
et al
2015
Laser Phys. Lett.
12 065105
https://doi.org/10.1088/1612-2011/12/6/065105
Buy this article in print
1
2
7/31/2017 All optical ultra-wideband signal generation and transmission using mode-locked laser incorporated with add-drop microring resonator - IOPscie…
http://iopscience.iop.org/article/10.1088/1612-2011/12/6/065105/pdf 2/3
The novel technique for generating the robust, ultra-wideband (UWB) signal in the optical
domain using a mode-locked laser incorporated with an add-drop microring resonator filter
is presented. In order to enable the down conversion of the UWB signal to the RF domain,
two wavelength ranges 1553.72 and 1553.92 nm, which are 24.65 GHz apart from each other,
are used. These wavelengths were generated based on a single longitudinal mode (SLM)
dual-wavelength fiber laser in a laser ring cavity. The upper wavelength of the generated
dual-wavelength laser is modulated with the UWB spectrum using an optical carrier
suppression (OCS) scheme and the lower wavelength is kept unmodulated. After beating the
modulated and unmodulated wavelength by launching into the photodiode, the 24 GHz
UWB signal can be generated to be applied to UWB over fiber (UWBoF) technology. The
error vector magnitude (EVM) for the signal transmission was calculated and the EVM
below 10% is achieved for 25 Km optical and 20 m wireless links.
Export citation and abstract BibTeX RIS
Access this article
Login options
Individual login
or
Institutional login
via Athens/Shibboleth
The computer you are using is not registered by an institution with a subscription to this article. Please log
in below. Find out more about journal subscriptions at your site.
Purchase this article online
Buy this article
By purchasing this article, you are accepting IOP's Terms and Conditions for Document Delivery. If you
would like to buy this article, but not online, please contact custserv@iop.org.
Make a recommendation
Recommend this journal
To gain access to this content, please complete the Recommendation Form and we will follow up with
your librarian or Institution on your behalf.
7/31/2017 All optical ultra-wideband signal generation and transmission using mode-locked laser incorporated with add-drop microring resonator - IOPscie…
http://iopscience.iop.org/article/10.1088/1612-2011/12/6/065105/pdf 3/3
Subscribe to this journal
Related content
JOURNAL ARTICLES
Tunable microwave output over a wide RF region generated by an optical dual-wavelength fiber laser
Generation of an ultra-stable dual-wavelength ytterbium-doped fiber laser using a photonic crystal fiber
Stable narrow spacing dual-wavelength Q-switched graphene oxide embedded in a photonic crystal fiber
Quadruple-wavelength tunable and dual-wavelength switchable ultrafast fiber laser
A tuneable, power efficient and narrow single longitudinal mode fibre ring laser using an inline dual-taper
fibre Mach–Zehnder filter
Switchable multi-wavelength fiber laser based on modal interference
... To compete for the future generation 5G network applications, the frequency shifts to millimeter wave (MMW) band is required and the technique known as radio over fiber (RoF) (Alavi et al. 2014a, b;Amiri et al. 2014aAmiri et al. , b, c, 2015aSoltanian et al. 2015;Xu et al. 2014). The salient features provide high tolerance, less latency for wireless transmission, good diversity and stable backhaul network. ...
... The salient features provide high tolerance, less latency for wireless transmission, good diversity and stable backhaul network. To provide such as a system, the ring bus based waveguide resonators is brought to the sense as it proves unexpected delegates in the form of various components such as a multiplexer, de-multiplexer, splitter and wavelength selection filter etc. (Ahmad et al. 2015;Alavi et al. 2014aAlavi et al. , b, 2015Amiri et al. 2016). In that elevation, another structural modification with material level (air-semiconductor) gives the strong adherence with respect to low loss (Alavi et al. 2016;Amiri et al. 2015a, b, c). ...
Dual-wavelength transmission system using double micro-resonator system for EMI healthcare applications
Article
Full-text available
  • Apr 2019
  • MICROSYST TECHNOL
To meet the 5G requirements for higher bandwidth, the focus has been shifted to millimeter waves paving the way to radio over fiber (RoF) in order to minimize radio losses. Dual wavelength transmission within RoF for electromagnetic immunity interference (EMI) can be utilized within local area network and long-haul transmission. Health care services will also be able to utilize the technology to transmit health-related data from thousands of patients to the specific destination by connecting to the long-haul fiber optic cable connection. To make dual-wavelength transmission stable and reliable, the formation of the two-wavelength light source is proposed in this paper by means of the double coupled micro-ring resonators. The proposed RoF system will be able to transmit EMI signals of patients over 300 km of optical fiber link and 3 m wireless link without the need for any intermediate signal amplifying device. All the patient’s data will be available to any doctor in any hospital securely by integrating with currently available wireless and the internet of things systems.
View
... Übertragungsgeschwindigkeiten und Rechenleistungen steigerten sich in den vergangenen Jahrzehnten um ein Vielfaches [Bre97,Pep17]. Vorangetrieben wird dieser Prozess durch neue technologische Ansätze und präzisere Fertigungsverfahren. Beispielsweise bieten, aufgrund des Einsatzes hochfrequenter, modengekoppelter Laser sowie hochpräziser Faserkomponenten [Sol15,Iu19] moderne Glasfaserleitung im Vergleich zu herkömmlichen Kupferleitungen massiv erhöhte Übertragungsbandbreiten [Oli14]. Die Herstellung immer leistungsfähigerer Komponenten stößt aufgrund der zunehmenden Miniaturisierung der Bauteile insbesondere im Bereich der Mikrochipherstellung zunehmend an physikalische Limitierungen, welche die Rechenleistung klassischer Komponenten in naher Zukunft begrenzen werden [Kis02,Wil17,The17]. ...
View
... Both the microring resonators have the same radius of 8 µm, and the power coupling coefficients are κ1 = κ2 = κ3 = 0.1. The effective area is 3.03 µm 2 , and The waveguide loss is α=0.5 dB/mm [33]. Due to a very small radius of the microring resonator which is about 8 µm, the waveguide loss will be then α=0.5 dB×10 -3 /µm which shows a negligible value. ...
Manipulating of nanometer spacing dual-wavelength by controlling the apodized grating depth in microring resonators
Article
Full-text available
  • Nov 2018
We propose a passive photonic design for an optically pumped laser system and tunable dual-wavelength generation application by employing optical nonlinear mode coupling of two coupled III–V semiconductor microring resonators, which is connected to a pump and drop waveguide buses. One of the two rings contains a grating, whereas the other has a planar surface. The mechanism underlying the dual-wavelength generation can be explained via the resonance detuning of the spectra that results in nonlinear mode mixing. The tunability of the wavelengths can be achieved by altering the grating depth of the microring resonator and the power coupling coefficients. In the grating design of the microring resonators, we have selected a trapezoidal-profiled apodized grating to obtain low reflectivity at the sidelobes. A time-domain traveling wave (TDTW) analysis yields an InGaAsP core refractive index of 3.3. This core is surrounded by a grating InP cladding with a refractive index of 3.2. We further confirm that the propagation of a Gaussian pulse input with a power of 10 mW and a bandwidth of 0.76 ps is well confined within the system mode propagation. The results show a 2:1 fan-out of two spectrally separate signals, which can be employed for compact and high functional sources on chips.
View
... Amiri et al. have shown that MRR can be used to generate multiple wavelengths when a soliton pulse is propagated inside the system [17] . Recently, some MRR systems, which are able to generate solitonic pulse shapes and WDM channels, are proposed [18,19] . Dense frequency channels can be produced when the soliton pulse is propagated within the nonlinear MRR system causing large bandwidth signals -which are applicable for wireless-assisted multi-NoC -to be achieved. ...
Wireless-assisted Multiple Network on Chip Using Microring Resonators
Article
  • Sep 2018
  • MICROPROCESS MICROSY
The multiple network-on-Chip (multi-NoC) architecture is an attractive solution to scale on-chip network bandwidth; however, its performance is influenced by its overall communication infrastructure. Incorporating wireless links attract the traffic and cause the power-gated components to stay in sleep state for a longer period of time. The presented research proposes a system generating discrete frequencies via a series of microring resonators to generate frequency channels with 200 MHz Full Width at Half Maximum (FWHM) and 2.5 GHz free spectral range (FSR) for wireless-assisted multi-NoC application. It also evaluates the proposed architecture tested with a 64-core processor with a mesh topology using synthetic traffic and the PARSEC benchmark. The results show that the average network power of the proposed architecture is 55.4% and 11.1% lower than traditional single-NoC and power-gating multi-NoC designs respectively. Furthermore, evaluation of network latency shows that the proposed architecture has an average reduction by 10.4% in comparison with power-gated multi-NoC design.
View
... By using the Kerr-Vernier effect, we propose to design a system to accomplish stereo sensors. By varying the input identical light sources a change in the refractive index of the device is caused by the nonlinear effect [18][19][20]. We have attempted to describe cell ...
View
... The nonlinear materials play an important role in photonic crystal fibers, optical waveguide and optical ring resonators [9][10][11][12], which has experienced a revolutionary development on the variety of applications such as optical filters, optical sensing, modulators, laser, broadband sources, telecommunications, SC generation and so on [13][14][15]. In these studies, a Kerr nonlinearity is assumed in such a way, the refractive index varies in response to the optical intensity instantaneously [16][17][18]. Due to compactness and suitability of the ring resonator waveguides, these devices have recently attracted considerable attention for the integrated photonics circuit applications. Recently several experimental and theoretical investigations were reported such as, in the case of the optical waveguide for SC generation in silicon nanowire, As 2 S 3 chalcogenide planar waveguide, ChG planar waveguides [19][20][21] etc. SC generations were generated by launching a femtosecond pulse polarized (soliton) in the nonlinear waveguide. ...
On-Chip Supercontinuum Generation in Nanostructured Ge 11.5 As 24 Se 64.5 Chalcogenide Waveguides using Panda-ring Resonator
Article
Full-text available
  • May 2018
The on-chip scale microring circuit is proposed to numerically investigate the supercontinuum (SC) generation of light power. The device is formed by the chalcogenide Panda-ring resonator with the nanoscale planar waveguide using Ge11.5As24Se64.5 chalcogenide glass channel waveguide, air-clad and MgF2 glass for lower cladding. The waveguide is designed to exhibit normal dispersion along with a low-energy pumped at 1.55 μm using a short pulse, which has the duration of 50 fs and peak power ranging from 1 W to 100 W. The numerical result obtained has shown a good-quality SC generation of both the spectral bandwidth and high output peak power. All SC spectral extended to more than 13 μm by cumulative Kerr nonlinearities. The obtained results can be useful for developing new experimental work in the important area of SC generation on compact chip broadband sources, which can be used in both infrared and radio wave applications.
View
... Electro-optic circuits have been used in various aspects to serve the current required information capacity, in which both electronic and optical signals can be applied and used incorporating in the information networks [1][2][3][4]. Currently, the requirement of the high capacity network is heading to the 5G protocol [5,6], in which the applications of the internet of thing (IoT) [6] will be realized. ...
On-chip Electro-optic Multiplexing Circuit using Serial Microring Boxcar Filters
Article
Full-text available
  • May 2018
We propose a new variant of electro-optic multiplexing scheme using the boxcar filter arrangement. The circuits consist of multistage add-drop multiplexers that can offer external input-output connections. Input from a single light source can be fed into the system through the input port or through the free-space from light fidelity (LiFi) node. The light signal is fed into boxcar filters and the roll-off bands are obtained. The output of the circuits is formed at the drop, through and the whispering gallery mode (WGM) node of the circuit output. By using the electro-optic conversion in Si-Graphene-Au layer stack, time division (TDM), wavelength division (WDM), frequency division multiplexing (FDM) can be performed. The simulations have shown that a combination of 7 roll-off bands with the maximum spectral widths or bandwidths of ∼6.09 µm or ∼7.63 THz can be obtained.
View
View
Four Wave Mixing Generation by Using Nonlinearity Material with Half-Panda Structure
Article
  • Feb 2019
  • OPTIK
By simulating the structure of half Panda waveguide base on nonlinear material, it was able to generate the four-wave mixing base on 3 picks which the highest pick was pump and the lowest power goes to converted. In this research the high Q factor showing the optimization for the waveguide was successful which was 2.58 × 10 ³ in drop port. better power transferring occurred with the nonlinear material has been used. It has been found that signal and pump intensity were higher than the converted values. Finite different time domain (FDTD) is the simulation that has been used in this modeling.
View
Computation of Ion Exchange Buried Microring Resonator Waveguide for THz Communication Applications
Article
Full-text available
  • Jun 2018
The ion exchange creates the optical buried waveguides, whereas it is the method that the glass doping occurs with the condition of existence of the mobile metal ions. The most common ion used is silver (Ag+) due to its broad variation in the refractive index. The proposed application presented in this work is to use the microring resonator (MRR) system based on the buried waveguides simulated by the ion exchange method. The passive MRRs are realized as the multi-wavelength transceiver, applicable in optical technologies such as the optical sensing, Terahertz (THz) communication and optical switching. The cross-sectional view of the simulated buried optical waveguide for the Ag+ concentrations of 0.8 mol/m³ is presented. The fundamental mode propagation is simulated using the time-domain traveling wave method, where the simulation of the optical power flow density and the electric field distributions of the buried waveguides were performed. The two coupled MRRs are used to generate tunable dual-wavelength with spacing in the range of Terahertz (THz). As results, the dual wavelengths in the range between 0.25 and 0.96 THz were generated at the throughput and drop port of the MRRs system.
View
Ring Resonator Systems to Perform Optical Communication Enhancement Using Soliton
Article
Full-text available
  • Jan 2015
The title explain new technique of secured and high capacity optical communication signals generation by using the micro and nano ring resonators. The pulses are known as soliton pulses which are more secured due to having the properties of chaotic and dark soliton signals with ultra short bandwidth. They have high capacity due to the fact that ring resonators are able to generate pulses in the form of solitons in multiples and train form. These pulses generated by ring resonators are suitable in optical communication due to use the compact and integrated rings system, easy to control, flexibility, less loss, application in long distance communication and many other advantages. Using these pulses overcome the problems such as losses during the propagation, long distances, error detection, using many repeaters or amplifiers, undetectable received signals, pulse broadening, overlapping and so on. This book show how to generate soliton pulses using ring resonators in the micro and nano range which can be used in optical communication to improve the transmission technique and quality of received signals in networks such as WiFi and wireless communication.
View
Switchable multi-wavelength and dual-scale soliton fiber laser incorporating cascaded chirped fiber Bragg gratings
Article
Full-text available
  • Feb 2015
A simple scheme of a switchable multi-wavelength and dual-scale soliton fiber laser is proposed by cascading three chirped fiber Bragg gratings (CFBGs). By managing the cavity dispersion and controlling the losses of attenuators, quadruple-wavelength switchable pulses are generated, including one dissipative soliton (DS) and three conventional solitons (CSs). The central wavelength of the DS is 1565 nm with a pulse duration of 12.5 ps which can be compressed to ~571 fs after a 70 m single mode fiber external to cavity. Three CSs are achieved at 1539.5, 1544.5, and 1549.5 nm with pulse durations of 9.6, 8.7, and 8.8 ps, corresponding to the CFBG-based comb spectral filtering. These results demonstrate that the proposed method offers potential opportunities to exploit the flexibly switchable multi- wavelength CS/DS-pulse sources at picosecond and femtosecond scales.
View
Generation and transmission of 3 × 3 w-band multi-input multi-output orthogonal frequency division multiplexing-radio-over-fiber signals using micro-ring resonators
Article
Full-text available
  • Nov 2014
Using the micro-ring resonator (MRR) system, the single and multi-carriers at frequencies of f 1 = 192.898 , f 2 = 192.990 , f 3 = 193.1 , f 4 = 193.315 , and f 5 = 193.537 THz with a free spectral range (FSR) of 92, 110, 215, and 222 GHz, respectively, are generated to be suitable for a radio-over-fiber (RoF) system based on multi-input multi-output (MIMO) with orthogonal frequency division multiplexing (OFDM). Demonstrated are the concepts of all-optical MIMO signal generation and its transmission over a 50 km single mode fiber (SMF) optical link and an up to 3 m wireless link. Sixty-four multi-carriers are used in the all-optical generation of three MIMO W-Band RF signals, where the single carriers ( f 3 − f 5 ) transport the signals over the RoF link. The bit error rate (BER) of the overall system performance is discussed; thus, the transmission of MIMO signals is feasible for up to an SMF path 50 km long and a wireless distance of 3 m.
View
All-optical generation of two IEEE802.11n signals for 2 × 2 MIMO-RoF via MRR system
Article
Full-text available
  • Dec 2014
A radio over fiber (RoF) system capable of very spectrally efficient data transmission and based on multiple-input and multiple-output (MIMO) and orthogonal frequency-division multiplexing (OFDM) is presented here. Carrier generation is the basic building block for implementation of OFDM transmission, and multi-carriers can be generated using the microring resonator (MRR) system. A series of MRRs incorporated with an add/drop filter system was utilized to generate multi-carriers in the 193.00999-193.01001 THz range, which were used to all-optically generate two MIMO WLAN RF signals suitable for the IEEE802.11n standard communication systems, and also generate single wavelengths at frequencies of 193.08, 193.1 and 193.12 THz with free spectral range (FSR) of 20 GHz used to optically transport the separated MIMO signals over a single mode fiber (SMF). The error vector magnitude (EVM) and bit-error-rate (BER) of overall system performance are discussed. Results show that the generated RF signals propagated wirelessly through MIMO channel using the 2×2 MIMO Tx antennas. There is an acceptable EVM variation for wireless distance lower than 70, 30 and 15 m It can be concluded that the transmission of both MIMO RF signals is feasible for up to a 50 km SMF path length and wireless distance of 15m.
View
Stable narrow spacing dual-wavelength Q-switched graphene oxide embedded in a photonic crystal fiber
Article
Full-text available
  • Aug 2014
  • LASER PHYS
An ultra-stable dual-wavelength saturable absorber based on a cladding-embedded commercial graphene oxide (GO) solution by capillary action in a solid core photonic crystal fiber (PCF) is demonstrated for the first time. The saturation absorption property is achieved through evanescent coupling between the guided light and the cladding-filled graphene layers. Stable spacing dual-wavelength fiber lasing is attained by controlling the polarization state of a simple 0.9 m long ring of highly doped Leikki Er80-8/125 erbium-doped fiber as the primary gain medium with PCF, polarization controller and tunable bandpass filter. Embedded GO is used to generate the desired pulsed output, and the laser is capable of generating pulses having a repetition rate of 24 kHz with an average output power and pulse energy of 0.167 mW and 8.98 nJ, respectively, at the maximum pump power of 220 mW.
View
Photonic crystal fiber based dual-wavelength Q-switched fiber laser using graphene oxide as a saturable absorber
Article
Full-text available
  • May 2014
A Q -switched dual-wavelength fiber laser with narrow channel spacing is proposed and demonstrated. The fiber laser is built around a 3 m long erbium doped fiber as the gain medium and a 10 cm long photonic crystal fiber (PCF) as the element used to generate the dual-wavelength output. The PCF has a solid core approximately 4.37 μm in diameter and is surrounded by microscopic air-holes with a diameter of about 5.06 μm each as well as a zero-dispersion wavelength of about 980 nm. A graphene oxide based saturable absorber is used to generate the desired pulsed output. At the maximum pump power of 72 mW the laser is capable of generating pulses with a repetition rate and pulse-width of 31.0 kHz and 7.0 μs, respectively, as well as an average output power and pulse energy of 0.086 mW and 2.8 nJ, respectively. The proposed fiber laser has substantial potential for use in applications that require longer duration pulsed outputs such as in range finding and terahertz radiation generation.
View
Generation and Wired/Wireless Transmission of IEEE802.16m Signal Using Solitons Generated By Microring Resonator
Article
Full-text available
  • May 2014
Multi-carrier generation is the main building block for generating WiMax signal. In order to use WiMax signal in radio over fiber applications the use of all optical generation of RF signals is required. To generate multi carriers optically, the system consisting of series of Microring Resonators (MRRs) incorporating with an add/drop filter system are used. Thus the high frequency (THz) solitons range of 193.29–193.35 THz at frequencies of 193.333, 193.3355 and 193.3388 THz with the Free Spectral Range (FSR) of 2.5 and 5.8 GHz could be performed using MRRs, providing required WiMax signal used in wired/wireless communication. The generated multi carriers are multiplexed with the single carrier soliton and transmitted through single mode fiber (SMF) after being beaten to photodiode, a WiMax signal is propagated wirelessly in transmitter antenna base station and is received by the second antenna located in the receiver. Here, based on the switching of channel 1 or channel 2, the 2.5 GHz or 5.8 GHz RF WiMax can be generated. When the RF signal is up-converted at the Receiver Central Office (RCO), the detected signal is analysed in order to evaluate the error vector magnitude (EVM) of each wireless channel. As results, both channels show a soft EVM variation for different path lengths, where the transmission of both channels is feasible for up to a 50 km SMF path length.
View
Coexistence of conventional solitons and stretched pulses in a fiber laser mode-locked by carbon nanotubes
Article
  • Apr 2015
We have proposed a nanotube-mode-locking fiber laser that can generate conventional solitons and stretched pulses in the same cavity. The net cavity dispersion of laser is slightly negative. The central wavelength and bandwidth of the conventional solitons are 1584.7 and 9.2 nm, respectively. The stretched pulse locates at 1572 nm with a bandwidth of 18.8 nm. The switchable mode-locking operation is mainly attributable to the bandwidth-dependent stretching factor that is tunable due to the spectral filtering effect induced by nonlinear polarization rotation.
View
Switchable dual-wavelength all-fiber laser mode-locked by carbon nanotubes
Article
  • Nov 2014
  • LASER PHYS
We have proposed a compact dual-wavelength all-fiber pulse laser based on a single-walled carbon nanotube and chirped fiber Bragg gratings (CFBGs). A transmission filter is composed of a circulator and two CFBGs and is capable of controlling the operation of the proposed fiber laser. Mode-locking operations can be switched between 1551.2 and 1548.6 nm with the appropriate adjustment of polarization controller. Our laser delivers the pulses with the spectral bandwidth of about 0.6 nm and the pulse duration of about 7 ps. This work provides a low-cost, stable, and dual-wavelength ultrafast-pulsed laser source suitable for practical applications.
View
Tunable microwave output over a wide RF region generated by an optical dual-wavelength fiber laser
Article
  • Aug 2014
  • LASER PHYS
The dual-wavelength fiber laser provides a compact, robust and stable platform for the generation of microwave signals. Two approaches towards generating microwave emissions using dual wavelengths are explored in this work, with both exploiting the heterodyning beat technique. Both approaches are based on a ring fiber laser with an erbium-doped fiber, having absorption coefficients of 16.0–20.0 dBm at 1531 nm and 11.0–13.0 dBm at 980 nm, serving as the active gain medium. A 10 cm long photonic crystal fiber with a solid core diameter of 4.37 μm and surrounded by air holes of 5.06 μm diameter with a separation of 5.52 μm between them serves to create the desired dual-wavelength output. A tunable band pass filter with bandwidth of 0.8 nm serves as a tuning mechanism together with a polarization controller. Channel spacings as narrow as 0.00043 nm can be realized, giving a microwave output of about 671.9 MHz. Furthermore, the channel spacing can be extended to as large as 0.03631 nm, giving a microwave emission in excess of 4.59 GHz. The output is highly stable, with little change in power or wavelength observed over a test period of 22 min.
View