The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
A R Chraplyvy - One of the best experts on this subject based on the ideXlab platform.
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m ary pulse position modulation and frequency shift keying with additional polarization phase modulation for high sensitivity optical transmission
Optics Express, 2011Co-Authors: S. Chandrasekhar, E. C. Burrows, T.h. Wood, Robert W. Tkach, Peter J Winzer, A R ChraplyvyAbstract:We present a new class of optical modulation formats based on the combination of m-ary pulse-position modulation (m-PPM) or m-ary frequency-shift keying (FSK) with additional polarization and/or phase modulation, which is applied on the information carrying pulses in the case of m-PPM or on the information carrying frequency carriers in the case of m-FSK. We describe the principle and implementation of this class of optical modulation formats, and formulate their theoretical receiver sensitivities in optically pre-amplified receivers. Pilot-assisted frequency-domain equalization, similar to that used in coherent optical orthogonal frequency-division multiplexing (CO-OFDM), is used for reliable channel estimation and compensation. CO-OFDM also allows m-FSK to be implemented with high spectral efficiency. As a particular format in this class, m-PPM in combination with polarization-division-multiplexed quadrature phase-shift keying (PDM-QPSK), termed as PQ-mPPM, offers superior receiver sensitivity in optically pre-amplified receivers at bit error ratios (BERs) around the thresholds of common forward-error correction codes. Record receiver sensitivities of 3.5 photons per bit (ppb) at BER = 10−3 and 2.7 ppb at BER = 1.5 × 10−2 are experimentally demonstrated at 2.5 Gb/s and 6.23 Gb/s using PQ-16PPM and PQ-4PPM, respectively. We further demonstrate the transmission of a 6.23-Gb/s PQ-4PPM signal over a 370-km unrepeatered ultra-large-area-fiber span with 71.7-dB total loss budget.
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m ary pulse position modulation and frequency shift keying with additional polarization phase modulation for high sensitivity optical transmission
Optics Express, 2011Co-Authors: Xiang Liu, E. C. Burrows, T.h. Wood, Robert W. Tkach, Peter J Winzer, S. Chandrasekhar, A R ChraplyvyAbstract:We present a new class of optical modulation formats based on the combination of m-ary pulse-position modulation (m-PPM) or m-ary frequency-shift keying (FSK) with additional polarization and/or phase modulation, which is applied on the information carrying pulses in the case of m-PPM or on the information carrying frequency carriers in the case of m-FSK. We describe the principle and implementation of this class of optical modulation formats, and formulate their theoretical receiver sensitivities in optically pre-amplified receivers. Pilot-assisted frequency-domain equalization, similar to that used in coherent optical orthogonal frequency-division multiplexing (CO-OFDM), is used for reliable channel estimation and compensation. CO-OFDM also allows m-FSK to be implemented with high spectral efficiency. As a particular format in this class, m-PPM in combination with polarization-division-multiplexed quadrature phase-shift keying (PDM-QPSK), termed as PQ-mPPM, offers superior receiver sensitivity in optically pre-amplified receivers at bit error ratios (BERs) around the thresholds of common forward-error correction codes. Record receiver sensitivities of 3.5 photons per bit (ppb) at BER = 10−3 and 2.7 ppb at BER = 1.5 × 10−2 are experimentally demonstrated at 2.5 Gb/s and 6.23 Gb/s using PQ-16PPM and PQ-4PPM, respectively. We further demonstrate the transmission of a 6.23-Gb/s PQ-4PPM signal over a 370-km unrepeatered ultra-large-area-fiber span with 71.7-dB total loss budget.
Masayuki Izutsu - One of the best experts on this subject based on the ideXlab platform.
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continuous phase frequency shift keying with external modulation
IEEE Journal of Selected Topics in Quantum Electronics, 2006Co-Authors: Takahide Sakamoto, Tetsuya Kawanishi, Masayuki IzutsuAbstract:A high-speed external modulation scheme for optical continuous-phase frequency-shift keying (CPFSK) is presented. In external frequency-shift keying (FSK) modulation using single-sideband modulation technology, an optical upper/lower sideband (USB/LSB) component with respect to a carrier frequency is selectively generated. However, the FSK-modulated signal has phase discontinuities at the timings of frequency shifts. To overcome the problem, we propose a synchronous control technique that enables continuous phase modulation. In the external CPFSK modulation, the USB/LSB is allowed to shift to the other state when their phases coincide with each other. It is shown that CPFSK with a zero-to-peak frequency deviation of 0.5times(bit rate) is achieved with this synchronous control. Occupant bandwidth is less than half that of the externally modulated incoherent FSK with phase discontinuities. At a modulation speed of 10 Gb/s, higher order sidelobes are highly suppressed by more than 20 dB at the 20-GHz offset, comparing to a conventional binary phase-shift keying (BPSK). By the use of a Mach-Zehnder interferometer with balanced photodetection, receiver sensitivity is 3-dB greater than that of an on-off keying, as well as a BPSK. In this paper, we report on the experimental demonstration of CPFSK modulation/demodulation. A six-channel wavelength-division-multiplexed, 10-Gb/s CPFSK modulation/demodulation was successfully demonstrated
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high speed optical dqpsk and fsk modulation using integrated mach zehnder interferometers
Optics Express, 2006Co-Authors: Tetsuya Kawanishi, Takahide Sakamoto, Tetsuya Miyazaki, Masayuki Izutsu, Takahisa Fujita, Shingo Mori, Kaoru Higuma, Junichiro IchikawaAbstract:We investigated an integrated optical modulator consisting of two Mach-Zehnder interferometers. The modulator can generate optical signals in various types of modulation formats, which have advantages for long-haul transmission, optical labeling, etc. By using a fabricated versatile optical modulator having traveling-wave electrodes designed for high-speed signals, we demonstrated generation of optical 40Gb/s frequency-shift-keying signals, which can be demodulated by an optical filter. 80Gb/s optical differential quadrature-shift-keying modulation was also demonstrated, where 40Gb/s in-phase and quadrature data were, simultaneously, fed to the modulator.
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novel modulation scheme for optical continuous phase frequency shift keying
Optics InfoBase Conference Papers, 2006Co-Authors: Takahide Sakamoto, Tetsuya Kawanishi, Tetsuya Miyazaki, Masayuki IzutsuAbstract:We propose a novel scheme for continuous-phase frequency-shift-keying (CP-FSK) optical modulation. By synchronizing the baseband signal with the clock for sideband generation, external CP-FSK modulation is demonstrated at 10 Gbit/s for the first time.
Takahide Sakamoto - One of the best experts on this subject based on the ideXlab platform.
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continuous phase frequency shift keying with external modulation
IEEE Journal of Selected Topics in Quantum Electronics, 2006Co-Authors: Takahide Sakamoto, Tetsuya Kawanishi, Masayuki IzutsuAbstract:A high-speed external modulation scheme for optical continuous-phase frequency-shift keying (CPFSK) is presented. In external frequency-shift keying (FSK) modulation using single-sideband modulation technology, an optical upper/lower sideband (USB/LSB) component with respect to a carrier frequency is selectively generated. However, the FSK-modulated signal has phase discontinuities at the timings of frequency shifts. To overcome the problem, we propose a synchronous control technique that enables continuous phase modulation. In the external CPFSK modulation, the USB/LSB is allowed to shift to the other state when their phases coincide with each other. It is shown that CPFSK with a zero-to-peak frequency deviation of 0.5times(bit rate) is achieved with this synchronous control. Occupant bandwidth is less than half that of the externally modulated incoherent FSK with phase discontinuities. At a modulation speed of 10 Gb/s, higher order sidelobes are highly suppressed by more than 20 dB at the 20-GHz offset, comparing to a conventional binary phase-shift keying (BPSK). By the use of a Mach-Zehnder interferometer with balanced photodetection, receiver sensitivity is 3-dB greater than that of an on-off keying, as well as a BPSK. In this paper, we report on the experimental demonstration of CPFSK modulation/demodulation. A six-channel wavelength-division-multiplexed, 10-Gb/s CPFSK modulation/demodulation was successfully demonstrated
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high speed optical dqpsk and fsk modulation using integrated mach zehnder interferometers
Optics Express, 2006Co-Authors: Tetsuya Kawanishi, Takahide Sakamoto, Tetsuya Miyazaki, Masayuki Izutsu, Takahisa Fujita, Shingo Mori, Kaoru Higuma, Junichiro IchikawaAbstract:We investigated an integrated optical modulator consisting of two Mach-Zehnder interferometers. The modulator can generate optical signals in various types of modulation formats, which have advantages for long-haul transmission, optical labeling, etc. By using a fabricated versatile optical modulator having traveling-wave electrodes designed for high-speed signals, we demonstrated generation of optical 40Gb/s frequency-shift-keying signals, which can be demodulated by an optical filter. 80Gb/s optical differential quadrature-shift-keying modulation was also demonstrated, where 40Gb/s in-phase and quadrature data were, simultaneously, fed to the modulator.
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novel modulation scheme for optical continuous phase frequency shift keying
Optics InfoBase Conference Papers, 2006Co-Authors: Takahide Sakamoto, Tetsuya Kawanishi, Tetsuya Miyazaki, Masayuki IzutsuAbstract:We propose a novel scheme for continuous-phase frequency-shift-keying (CP-FSK) optical modulation. By synchronizing the baseband signal with the clock for sideband generation, external CP-FSK modulation is demonstrated at 10 Gbit/s for the first time.
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ultra wide band signal generation using high speed optical frequency shift keying technique
International Topical Meeting on Microwave Photonics, 2004Co-Authors: Tetsuya Kawanishi, Takahide Sakamoto, M IzutsuAbstract:We proposed a novel technique for generation of micro- or millimeter-wave pulses using optical frequency-shift-keying (FSK) modulation. FSK signals were obtained by an integrated four optical phase modulators.
Liesbet Lagae - One of the best experts on this subject based on the ideXlab platform.
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frequency shift keying in vortex based spin torque oscillators
Journal of Applied Physics, 2011Co-Authors: Mauricio Manfrini, T Devolder, Joovon Kim, P Crozat, C Chappert, W Van Roy, Liesbet LagaeAbstract:Vortex-based spin-torque oscillators can be made from extended spin valves connected to an electrical nanocontact. We study the implementation of frequency shift keying modulation in these oscillators. Upon a square modulation of the current in the 10 MHz range, the vortex frequency follows the current command, with easy identification of the two swapping frequencies in the spectral measurements. The frequency distribution of the output power can be accounted for by convolution transformations of the dc current vortex waveform, and the current modulation. Modeling indicates that the frequency transitions are phase coherent and last less than 25 ns. Complementing the multi-octave tunability and first-class agility, the capability of frequency shift keying modulation is an additional milestone for the implementation of vortex-based oscillators in radio frequency circuits.
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frequency shift keying in vortex based spin torque oscillators
arXiv: Materials Science, 2010Co-Authors: Mauricio Manfrini, T Devolder, Joovon Kim, P Crozat, C Chappert, W Van Roy, Liesbet LagaeAbstract:Vortex-based spin-torque oscillators can be made from extended spin valves connected to an electrical nanocontact. We study the implementation of frequency shift keying modulation in these oscillators. Upon a square modulation of the current in the 10 MHz range, the vortex frequency follows the current command, with easy identification of the two swapping frequencies in the spectral measurements. The frequency distribution of the output power can be accounted for by convolution transformations of the dc current vortex waveform, and the current modulation. Modeling indicates that the frequency transitions are phase coherent and last less than 25 ns. Complementing the multi-octave tunability and first-class agility, the capability of frequency shift keying modulation is an additional milestone for the implementation of vortex-based oscillators in RF circuit.
Tetsuya Kawanishi - One of the best experts on this subject based on the ideXlab platform.
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continuous phase frequency shift keying with external modulation
IEEE Journal of Selected Topics in Quantum Electronics, 2006Co-Authors: Takahide Sakamoto, Tetsuya Kawanishi, Masayuki IzutsuAbstract:A high-speed external modulation scheme for optical continuous-phase frequency-shift keying (CPFSK) is presented. In external frequency-shift keying (FSK) modulation using single-sideband modulation technology, an optical upper/lower sideband (USB/LSB) component with respect to a carrier frequency is selectively generated. However, the FSK-modulated signal has phase discontinuities at the timings of frequency shifts. To overcome the problem, we propose a synchronous control technique that enables continuous phase modulation. In the external CPFSK modulation, the USB/LSB is allowed to shift to the other state when their phases coincide with each other. It is shown that CPFSK with a zero-to-peak frequency deviation of 0.5times(bit rate) is achieved with this synchronous control. Occupant bandwidth is less than half that of the externally modulated incoherent FSK with phase discontinuities. At a modulation speed of 10 Gb/s, higher order sidelobes are highly suppressed by more than 20 dB at the 20-GHz offset, comparing to a conventional binary phase-shift keying (BPSK). By the use of a Mach-Zehnder interferometer with balanced photodetection, receiver sensitivity is 3-dB greater than that of an on-off keying, as well as a BPSK. In this paper, we report on the experimental demonstration of CPFSK modulation/demodulation. A six-channel wavelength-division-multiplexed, 10-Gb/s CPFSK modulation/demodulation was successfully demonstrated
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high speed optical dqpsk and fsk modulation using integrated mach zehnder interferometers
Optics Express, 2006Co-Authors: Tetsuya Kawanishi, Takahide Sakamoto, Tetsuya Miyazaki, Masayuki Izutsu, Takahisa Fujita, Shingo Mori, Kaoru Higuma, Junichiro IchikawaAbstract:We investigated an integrated optical modulator consisting of two Mach-Zehnder interferometers. The modulator can generate optical signals in various types of modulation formats, which have advantages for long-haul transmission, optical labeling, etc. By using a fabricated versatile optical modulator having traveling-wave electrodes designed for high-speed signals, we demonstrated generation of optical 40Gb/s frequency-shift-keying signals, which can be demodulated by an optical filter. 80Gb/s optical differential quadrature-shift-keying modulation was also demonstrated, where 40Gb/s in-phase and quadrature data were, simultaneously, fed to the modulator.
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novel modulation scheme for optical continuous phase frequency shift keying
Optics InfoBase Conference Papers, 2006Co-Authors: Takahide Sakamoto, Tetsuya Kawanishi, Tetsuya Miyazaki, Masayuki IzutsuAbstract:We propose a novel scheme for continuous-phase frequency-shift-keying (CP-FSK) optical modulation. By synchronizing the baseband signal with the clock for sideband generation, external CP-FSK modulation is demonstrated at 10 Gbit/s for the first time.
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ultra wide band radio signal generation using optical frequency shift keying technique
IEEE Microwave and Wireless Components Letters, 2005Co-Authors: Tetsuya Kawanishi, T Sakamoto, M IzutsuAbstract:We proposed a novel technique for generation of micro- or millimeter-wave pulses using optical frequency-shift-keying (FSK) modulation. FSK signals were obtained by an integrated four optical phase modulators. The pulses can be obtained as an optical beat of two spectral components, during transient FSK state which is shorter than 100 ps.
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ultra wide band signal generation using high speed optical frequency shift keying technique
International Topical Meeting on Microwave Photonics, 2004Co-Authors: Tetsuya Kawanishi, Takahide Sakamoto, M IzutsuAbstract:We proposed a novel technique for generation of micro- or millimeter-wave pulses using optical frequency-shift-keying (FSK) modulation. FSK signals were obtained by an integrated four optical phase modulators.
