Romli Mohamad - Academia.edu (original) (raw)
Papers by Romli Mohamad
Microwave and Optical Technology Letters, 2007
This paper presents the performance evaluation of a duo-stage SOA based All-Optical Multicasting ... more This paper presents the performance evaluation of a duo-stage SOA based All-Optical Multicasting capable Switch architecture suitable for the requirements of Grid Networking. SOAs based devices are located at the input and the output ports of the switch. The SOAs located at the input port serves as a multicasting and routing device feeding the signals into an N × N arrayed waveguide gratings and the SOAs at the output are regenerators to restore the quality of the signals before sending them into the network. This design uses the non-linearity processes in SOA such as Cross Gain Modulation and Cross Phase Modulation to achieve a maximum of 1–16 multicast at a bit-rate of 10 Gbps within the all-optical switch. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 59–62, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22031
Microwave and Optical Technology Letters, 2006
We present the experimental investigation of a counter-pumped double-pass discrete Raman amplifie... more We present the experimental investigation of a counter-pumped double-pass discrete Raman amplifier with and without a pump reflector. The pump reflector is constructed with high-reflectivity fiber Bragg grating. Gain improvement is obtained as a result of pump recycling, in comparison to the conventional double-pass Raman amplifier. Noise-figure degradation is found for large signals in the proposed Raman amplifier due to the enhanced double-Rayleigh scattering and bidirectional pumping caused by the pump reflector. The impact of pump-to-signal relative intensity noise in the experimental work is minimized by utilizing Fabry–Perot pump lasers. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 777–779, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21473
Laser Physics, 2009
A simple configuration for the reduction of stimulated Brillouin scattering threshold in photonic... more A simple configuration for the reduction of stimulated Brillouin scattering threshold in photonic crystal fiber is presented. The threshold reduction is contributed by the bidirectional pumping scheme through the reflection of transmitted Brillouin pump back to the gain medium. The pump recycling scheme has greatly reduced the Brillouin threshold of a 200-m long of photonic crystal fiber from 50 to 30 mW of Brillouin pump power.
This article discusses the optical-SNR variation of Stokes lines in BRFL. This variation is partl... more This article discusses the optical-SNR variation of Stokes lines in BRFL. This variation is partly attributed to the cavity modes interaction through intraline-FWM residing the same spectralwidth. The worst OSNR is obtained at 650mW RPP and 1555nm BPW. The improvement is obtained for the RPP beyond 650mW.
Laser Physics Letters, 2008
We demonstrate a dual-stage gain-clamped erbiumdoped fiber amplifier. The first-stage amplifier c... more We demonstrate a dual-stage gain-clamped erbiumdoped fiber amplifier. The first-stage amplifier consists of a short length of erbium-doped fiber to produce low noise figures. The second-stage is constructed from a counter-propagating ringlaser, in which the signals and the lasing wavelength propagate in the opposite direction. The lasing wavelength is selected via a reflective-type of fiber Bragg grating. The gain-clamping mechanism can be adjusted by either changing the fiber Bragg grating reflectivity or center wavelength. The noise figure penalty is about 1.5 dB for the gain-clamping value from 11 dB to 20.5 dB. (© 2008 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA)
Optics Letters, 2006
We demonstrate a multiple-wavelength Brillouin comb laser with cooperative Rayleigh scattering th... more We demonstrate a multiple-wavelength Brillouin comb laser with cooperative Rayleigh scattering that uses Raman amplification in dispersion-compensating fiber. The laser resonator is a linear cavity formed by reflector at each end of the dispersion-compensating fiber to improve the reflectivity of the Brillouin Stokes comb. Multiple Brillouin Stokes generation has been improved in terms of optical signal-to-noise ratio and power-level fluctuation between neighboring channels. Furthermore, the linewidth of the Brillouin Stokes is uniform within the laser output bandwidth.
I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fi... more I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fiber in a cost-effective manner. A Passive Optical Network (PON) technology has no active elements in the field and, thus, power and heat issues can be eliminated. The system also ...
I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fi... more I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fiber in a cost-effective manner. A Passive Optical Network (PON) technology has no active elements in the field and, thus, power and heat issues can be eliminated. The system also ...
This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, bu... more This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, burst and packet based traffic and also perform all optical multicasting. This switch design is based upon a wavelength routed switching matrix with the used of SOAs as wavelength converters and also to perform multicasting. Optical Switches with such capabilities are essential for future Optical Grid Networking. Physical performance of the MPOS at 10 Gbps will be presented in this paper.
This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, bu... more This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, burst and packet based traffic and also perform all optical multicasting. This switch design is based upon a wavelength routed switching matrix with the used of SOAs as wavelength converters and also to perform multicasting. Optical Switches with such capabilities are essential for future Optical Grid Networking. Physical performance of the MPOS at 10 Gbps will be presented in this paper.
This work presents a novel routing protocol based MPOS (B.H.L. Lee et al., 2006), which is used i... more This work presents a novel routing protocol based MPOS (B.H.L. Lee et al., 2006), which is used in the construction of the multiprotocol switch for multimedia traffic. The MPOS routing segregates the different types of multimedia traffic into dedicated classes/priorities and assigns a light path for each of them. Experimental results of the MPOS routing optimize cost of the maximum end-to-end delay at high traffic load.
I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fi... more I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fiber in a cost-effective manner. A Passive Optical Network (PON) technology has no active elements in the field and, thus, power and heat issues can be eliminated. The system also ...
IEEE Photonics Technology Letters, 2006
The letter presents a study on the performance of an all-optical multicasting technique utilizing... more The letter presents a study on the performance of an all-optical multicasting technique utilizing the nonlinearity of semiconductor optical amplifier (SOA) technology for all-optical grid computing network. The technique not only has the capability to optically control the degree of multicasting but also performs all-optical switching simultaneously. Experimental results show the design's capability to multicast an incoming 10-Gb/s optical signal onto 16 outgoing signals using cross-gain modulation in a single SOA. A second SOA is also included in the design as a 2R regenerator.
This work presents a novel routing protocol based MPOS (B.H.L. Lee et al., 2006), which is used i... more This work presents a novel routing protocol based MPOS (B.H.L. Lee et al., 2006), which is used in the construction of the multiprotocol switch for multimedia traffic. The MPOS routing segregates the different types of multimedia traffic into dedicated classes/priorities and assigns a light path for each of them. Experimental results of the MPOS routing optimize cost of the maximum end-to-end delay at high traffic load.
I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fi... more I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fiber in a cost-effective manner. A Passive Optical Network (PON) technology has no active elements in the field and, thus, power and heat issues can be eliminated. The system also ...
This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, bu... more This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, burst and packet based traffic and also perform all optical multicasting. This switch design is based upon a wavelength routed switching matrix with the used of SOAs as wavelength converters and also to perform multicasting. Optical Switches with such capabilities are essential for future Optical Grid Networking. Physical performance of the MPOS at 10 Gbps will be presented in this paper.
Microwave and Optical Technology Letters, 2006
An all-optical gain-clamped Raman fiber amplifier (RFA) based on the ring-lasing technique using ... more An all-optical gain-clamped Raman fiber amplifier (RFA) based on the ring-lasing technique using a pair of circulators is demonstrated experimentally. The RFA is powered using a pair of 1465-nm pump laser diodes, which provide a peak gain at around 1565 nm. The analyses of the gain and the noise figure are carried out using different lasing wavelengths between 1550 and 1565 nm. The gain and noise figure variations are 0.4 and 0.5 dB in the gain-clamping range, respectively. We observe a strong influence of pump-signal relative-intensity noise transfer, which results in a noise-figure penalty at the signal. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 721–724, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21455
IEEE Photonics Technology Letters, 2006
The letter presents a study on the performance of an all-optical multicasting technique utilizing... more The letter presents a study on the performance of an all-optical multicasting technique utilizing the nonlinearity of semiconductor optical amplifier (SOA) technology for all-optical grid computing network. The technique not only has the capability to optically control the degree of multicasting but also performs all-optical switching simultaneously. Experimental results show the design's capability to multicast an incoming 10-Gb/s optical signal onto 16 outgoing signals using cross-gain modulation in a single SOA. A second SOA is also included in the design as a 2R regenerator.
This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, bu... more This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, burst and packet based traffic and also perform all optical multicasting. This switch design is based upon a wavelength routed switching matrix with the used of SOAs as wavelength converters and also to perform multicasting. Optical Switches with such capabilities are essential for future Optical Grid Networking. Physical performance of the MPOS at 10 Gbps will be presented in this paper.
I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fi... more I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fiber in a cost-effective manner. A Passive Optical Network (PON) technology has no active elements in the field and, thus, power and heat issues can be eliminated. The system also ...
Microwave and Optical Technology Letters, 2007
This paper presents the performance evaluation of a duo-stage SOA based All-Optical Multicasting ... more This paper presents the performance evaluation of a duo-stage SOA based All-Optical Multicasting capable Switch architecture suitable for the requirements of Grid Networking. SOAs based devices are located at the input and the output ports of the switch. The SOAs located at the input port serves as a multicasting and routing device feeding the signals into an N × N arrayed waveguide gratings and the SOAs at the output are regenerators to restore the quality of the signals before sending them into the network. This design uses the non-linearity processes in SOA such as Cross Gain Modulation and Cross Phase Modulation to achieve a maximum of 1–16 multicast at a bit-rate of 10 Gbps within the all-optical switch. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 59–62, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22031
Microwave and Optical Technology Letters, 2006
We present the experimental investigation of a counter-pumped double-pass discrete Raman amplifie... more We present the experimental investigation of a counter-pumped double-pass discrete Raman amplifier with and without a pump reflector. The pump reflector is constructed with high-reflectivity fiber Bragg grating. Gain improvement is obtained as a result of pump recycling, in comparison to the conventional double-pass Raman amplifier. Noise-figure degradation is found for large signals in the proposed Raman amplifier due to the enhanced double-Rayleigh scattering and bidirectional pumping caused by the pump reflector. The impact of pump-to-signal relative intensity noise in the experimental work is minimized by utilizing Fabry–Perot pump lasers. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 777–779, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21473
Laser Physics, 2009
A simple configuration for the reduction of stimulated Brillouin scattering threshold in photonic... more A simple configuration for the reduction of stimulated Brillouin scattering threshold in photonic crystal fiber is presented. The threshold reduction is contributed by the bidirectional pumping scheme through the reflection of transmitted Brillouin pump back to the gain medium. The pump recycling scheme has greatly reduced the Brillouin threshold of a 200-m long of photonic crystal fiber from 50 to 30 mW of Brillouin pump power.
This article discusses the optical-SNR variation of Stokes lines in BRFL. This variation is partl... more This article discusses the optical-SNR variation of Stokes lines in BRFL. This variation is partly attributed to the cavity modes interaction through intraline-FWM residing the same spectralwidth. The worst OSNR is obtained at 650mW RPP and 1555nm BPW. The improvement is obtained for the RPP beyond 650mW.
Laser Physics Letters, 2008
We demonstrate a dual-stage gain-clamped erbiumdoped fiber amplifier. The first-stage amplifier c... more We demonstrate a dual-stage gain-clamped erbiumdoped fiber amplifier. The first-stage amplifier consists of a short length of erbium-doped fiber to produce low noise figures. The second-stage is constructed from a counter-propagating ringlaser, in which the signals and the lasing wavelength propagate in the opposite direction. The lasing wavelength is selected via a reflective-type of fiber Bragg grating. The gain-clamping mechanism can be adjusted by either changing the fiber Bragg grating reflectivity or center wavelength. The noise figure penalty is about 1.5 dB for the gain-clamping value from 11 dB to 20.5 dB. (© 2008 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA)
Optics Letters, 2006
We demonstrate a multiple-wavelength Brillouin comb laser with cooperative Rayleigh scattering th... more We demonstrate a multiple-wavelength Brillouin comb laser with cooperative Rayleigh scattering that uses Raman amplification in dispersion-compensating fiber. The laser resonator is a linear cavity formed by reflector at each end of the dispersion-compensating fiber to improve the reflectivity of the Brillouin Stokes comb. Multiple Brillouin Stokes generation has been improved in terms of optical signal-to-noise ratio and power-level fluctuation between neighboring channels. Furthermore, the linewidth of the Brillouin Stokes is uniform within the laser output bandwidth.
I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fi... more I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fiber in a cost-effective manner. A Passive Optical Network (PON) technology has no active elements in the field and, thus, power and heat issues can be eliminated. The system also ...
I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fi... more I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fiber in a cost-effective manner. A Passive Optical Network (PON) technology has no active elements in the field and, thus, power and heat issues can be eliminated. The system also ...
This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, bu... more This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, burst and packet based traffic and also perform all optical multicasting. This switch design is based upon a wavelength routed switching matrix with the used of SOAs as wavelength converters and also to perform multicasting. Optical Switches with such capabilities are essential for future Optical Grid Networking. Physical performance of the MPOS at 10 Gbps will be presented in this paper.
This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, bu... more This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, burst and packet based traffic and also perform all optical multicasting. This switch design is based upon a wavelength routed switching matrix with the used of SOAs as wavelength converters and also to perform multicasting. Optical Switches with such capabilities are essential for future Optical Grid Networking. Physical performance of the MPOS at 10 Gbps will be presented in this paper.
This work presents a novel routing protocol based MPOS (B.H.L. Lee et al., 2006), which is used i... more This work presents a novel routing protocol based MPOS (B.H.L. Lee et al., 2006), which is used in the construction of the multiprotocol switch for multimedia traffic. The MPOS routing segregates the different types of multimedia traffic into dedicated classes/priorities and assigns a light path for each of them. Experimental results of the MPOS routing optimize cost of the maximum end-to-end delay at high traffic load.
I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fi... more I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fiber in a cost-effective manner. A Passive Optical Network (PON) technology has no active elements in the field and, thus, power and heat issues can be eliminated. The system also ...
IEEE Photonics Technology Letters, 2006
The letter presents a study on the performance of an all-optical multicasting technique utilizing... more The letter presents a study on the performance of an all-optical multicasting technique utilizing the nonlinearity of semiconductor optical amplifier (SOA) technology for all-optical grid computing network. The technique not only has the capability to optically control the degree of multicasting but also performs all-optical switching simultaneously. Experimental results show the design's capability to multicast an incoming 10-Gb/s optical signal onto 16 outgoing signals using cross-gain modulation in a single SOA. A second SOA is also included in the design as a 2R regenerator.
This work presents a novel routing protocol based MPOS (B.H.L. Lee et al., 2006), which is used i... more This work presents a novel routing protocol based MPOS (B.H.L. Lee et al., 2006), which is used in the construction of the multiprotocol switch for multimedia traffic. The MPOS routing segregates the different types of multimedia traffic into dedicated classes/priorities and assigns a light path for each of them. Experimental results of the MPOS routing optimize cost of the maximum end-to-end delay at high traffic load.
I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fi... more I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fiber in a cost-effective manner. A Passive Optical Network (PON) technology has no active elements in the field and, thus, power and heat issues can be eliminated. The system also ...
This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, bu... more This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, burst and packet based traffic and also perform all optical multicasting. This switch design is based upon a wavelength routed switching matrix with the used of SOAs as wavelength converters and also to perform multicasting. Optical Switches with such capabilities are essential for future Optical Grid Networking. Physical performance of the MPOS at 10 Gbps will be presented in this paper.
Microwave and Optical Technology Letters, 2006
An all-optical gain-clamped Raman fiber amplifier (RFA) based on the ring-lasing technique using ... more An all-optical gain-clamped Raman fiber amplifier (RFA) based on the ring-lasing technique using a pair of circulators is demonstrated experimentally. The RFA is powered using a pair of 1465-nm pump laser diodes, which provide a peak gain at around 1565 nm. The analyses of the gain and the noise figure are carried out using different lasing wavelengths between 1550 and 1565 nm. The gain and noise figure variations are 0.4 and 0.5 dB in the gain-clamping range, respectively. We observe a strong influence of pump-signal relative-intensity noise transfer, which results in a noise-figure penalty at the signal. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 721–724, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21455
IEEE Photonics Technology Letters, 2006
The letter presents a study on the performance of an all-optical multicasting technique utilizing... more The letter presents a study on the performance of an all-optical multicasting technique utilizing the nonlinearity of semiconductor optical amplifier (SOA) technology for all-optical grid computing network. The technique not only has the capability to optically control the degree of multicasting but also performs all-optical switching simultaneously. Experimental results show the design's capability to multicast an incoming 10-Gb/s optical signal onto 16 outgoing signals using cross-gain modulation in a single SOA. A second SOA is also included in the design as a 2R regenerator.
This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, bu... more This paper presents a novel optical switch, MPOS concept which is capable of handling circuit, burst and packet based traffic and also perform all optical multicasting. This switch design is based upon a wavelength routed switching matrix with the used of SOAs as wavelength converters and also to perform multicasting. Optical Switches with such capabilities are essential for future Optical Grid Networking. Physical performance of the MPOS at 10 Gbps will be presented in this paper.
I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fi... more I. INTRODUCTION The FTTH system is just now coming to the market and leverages the benefits of fiber in a cost-effective manner. A Passive Optical Network (PON) technology has no active elements in the field and, thus, power and heat issues can be eliminated. The system also ...