The Experts below are selected from a list of 5994 Experts worldwide ranked by ideXlab platform
H R Fetterman - One of the best experts on this subject based on the ideXlab platform.
-
nonlinear intermodulation distortion suppression in coherent analog fiber Optic Link using electro Optic polymeric dual parallel mach zehnder modulator
2011Co-Authors: Larry R Dalton, H R FettermanAbstract:A linearized dual parallel Mach-Zehnder modulator (DPMZM) based on electro-Optic (EO) polymer was both fabricated, and experimentally used to suppress the third-order intermodulation distortion (IMD3) in a coherent analog fiber Optic Link. This Optical transmitter design was based on a new EO chromophore called B10, which was synthesized for applications dealing with the fiber-Optic communication systems. The chromophore was mixed with amorphous polycarbonate (APC) to form the waveguide’s core material. The DPMZM was configured with two MZMs, of different lengths in parallel, with unbalanced input and output couplers and a phase shifter in one arm. In this configuration each of the MZMs carried a different Optical power, and imposed a different depth of Optical modulation. When the two Optical beams from the MZMs were combined to generate the transmitted signal it was possible to set the IMD3 produced by each modulator to be equal in amplitude but 180° out of phase from the other. Therefore, the resulting IMD3 of the DPMZM transmitter was effectively canceled out during two-tone experiments. A reduction of the IMD3 below the noise floor was observed while leaving fifth-order distortion (IMD5) as the dominant IMD product. This configuration has the capability of broadband operation and shot-noise limited operation simultaneously.
-
a broadband linearized coherent analog fiber Optic Link employing dual parallel mach zehnder modulators
2009Co-Authors: Guanghao Zhu, Wei Liu, H R FettermanAbstract:A composite Optical transmitter based on dual parallel Mach-Zehnder modulators is proposed to linearize double-sideband suppressed-carrier coherent analog fiber-Optic Links. The optimization condition for achieving the best spurious-free dynamic range (SFDR) is discussed, with a simple and exact expression for the maximized SFDR being derived. Unlike other existing linearization schemes, the proposed technique has the advantages of broadband operation and shot-noise-limited signal-to-noise ratio at the same time. For a lossless Link employing a transmitter laser with moderate Optical power of 100 mW, a broadband SFDR as high as 144 dB middot Hz4/5 is theoretically predicted.
Jianqiang Li - One of the best experts on this subject based on the ideXlab platform.
-
intermodulation distortion suppression for intensity modulated analog fiber Optic Link incorporating Optical carrier band processing
2013Co-Authors: Kun Xu, Jianqiang LiAbstract:An intermodulation distortion suppression method based on the Optical carrier band processing is demonstrated. A systematic analysis of the main Optical spectrum contributors for the third-order intermodulation distortion in the nonlinear system is presented. Theoretical analysis shows that the third-order intermodulation distortion terms can cancel each other if a proper phase shifting is imposed to the Optical carrier band. We experimentally demonstrate the approach with a two-tone test and a suppression of about 33 dB in the third-order intermodulation distortion is obtained. Experimental results show that an overall fundamental to third-order intermodulation distortion ratio of up to 64 dB is achieved and the Link dynamic range is improved by 14.7 dB, compared with the conventional Link without the proposed Optical carrier band processing.
-
intermodulation distortion suppression for intensity modulated analog fiber Optic Link incorporating Optical carrier band processing
2013Co-Authors: Kun Xu, Jianqiang LiAbstract:An intermodulation distortion suppression method based on the Optical carrier band processing is demonstrated. A systematic analysis of the main Optical spectrum contributors for the third-order intermodulation distortion in the nonlinear system is presented. Theoretical analysis shows that the third-order intermodulation distortion terms can cancel each other if a proper phase shifting is imposed to the Optical carrier band. We experimentally demonstrate the approach with a two-tone test and a suppression of about 33 dB in the third-order intermodulation distortion is obtained. Experimental results show that an overall fundamental to third-order intermodulation distortion ratio of up to 64 dB is achieved and the Link dynamic range is improved by 14.7 dB, compared with the conventional Link without the proposed Optical carrier band processing.
Kun Xu - One of the best experts on this subject based on the ideXlab platform.
-
intermodulation distortion suppression for intensity modulated analog fiber Optic Link incorporating Optical carrier band processing
2013Co-Authors: Kun Xu, Jianqiang LiAbstract:An intermodulation distortion suppression method based on the Optical carrier band processing is demonstrated. A systematic analysis of the main Optical spectrum contributors for the third-order intermodulation distortion in the nonlinear system is presented. Theoretical analysis shows that the third-order intermodulation distortion terms can cancel each other if a proper phase shifting is imposed to the Optical carrier band. We experimentally demonstrate the approach with a two-tone test and a suppression of about 33 dB in the third-order intermodulation distortion is obtained. Experimental results show that an overall fundamental to third-order intermodulation distortion ratio of up to 64 dB is achieved and the Link dynamic range is improved by 14.7 dB, compared with the conventional Link without the proposed Optical carrier band processing.
-
intermodulation distortion suppression for intensity modulated analog fiber Optic Link incorporating Optical carrier band processing
2013Co-Authors: Kun Xu, Jianqiang LiAbstract:An intermodulation distortion suppression method based on the Optical carrier band processing is demonstrated. A systematic analysis of the main Optical spectrum contributors for the third-order intermodulation distortion in the nonlinear system is presented. Theoretical analysis shows that the third-order intermodulation distortion terms can cancel each other if a proper phase shifting is imposed to the Optical carrier band. We experimentally demonstrate the approach with a two-tone test and a suppression of about 33 dB in the third-order intermodulation distortion is obtained. Experimental results show that an overall fundamental to third-order intermodulation distortion ratio of up to 64 dB is achieved and the Link dynamic range is improved by 14.7 dB, compared with the conventional Link without the proposed Optical carrier band processing.
F Bucholtz - One of the best experts on this subject based on the ideXlab platform.
-
analysis of an analog fiber Optic Link employing a low biased mach zehnder modulator followed by an erbium doped fiber amplifier
2009Co-Authors: Vincent J Urick, M Godinez, P S Devgan, Jason D Mckinney, F BucholtzAbstract:In this paper, a complete analysis of an analog fiber-Optic Link employing a low-biased Mach-Zehnder modulator followed by Optical amplification with an erbium-doped fiber amplifier is presented. The expressions for RF gain, RF noise figure, second- and third-order intercept points, and spurious-free dynamic range are derived. Experimental data are employed to support the analytical results, and the optimal bias points for the metrics are demonstrated.
-
wide band qam over fiber using phase modulation and interferometric demodulation
2004Co-Authors: Vincent J Urick, J X Qiu, F BucholtzAbstract:Transmission of microwave quadrature amplitude modulation over an all-Raman 105-km fiber-Optic Link is demonstrated. The Link employs Optical phase modulation and single-port interferometric demodulation to deliver up to 6 Gb/s in a single channel.
R.d. Esman - One of the best experts on this subject based on the ideXlab platform.
-
photodetector nonlinearity limitations on a high dynamic range 3 ghz fiber Optic Link
1998Co-Authors: K J Williams, L T Nichols, R.d. EsmanAbstract:The performance of a dc to 3 GHz externally modulated Link utilizing balanced high-power photodetection is presented. Nonlinearity measurements of high power photodiodes show 1 dB compression currents in excess of 55 mA and an output third-order intercept point of +32 to +34 dBm. These high current photodetectors permit the use of high power lasers as external modulator sources for low noise fiber Optic Links with only small degradations in the predicted Link dynamic range. An externally modulated Link with a 240 mW Nd:YAG laser, a dual-output 4-V V, (dc) modulator, and balanced 100 mA total photocurrent yielded a Link noise figure from 15.5 to 17.5 dB, a spur-free dynamic range of 119.5 dBHz/sup 2/3/, and a 1-dB compression dynamic range of 168.4 dBHz.
-
externally modulated 3 ghz fibre Optic Link utilising high current and balanced detection
1997Co-Authors: K J Williams, L T Nichols, R.d. EsmanAbstract:The performance of a DC to 3 GHz externally modulated Link utilising balanced high-power photodetectors is presented. High power photodiodes with 1 dB compression currents in excess of 56 mA are used with a 240 mW NdYAG laser, a dual-output 4 V V/sub x/ modulator, and balanced 100 mA total photocurrent yielding a Link gain of 3 to 6 dB and a noise figure of 15.5-17.5 dB.
-
a low loss downconverting analog fiber Optic Link
1995Co-Authors: G K Gopalakrishnan, W K Burns, R P Moeller, M M Howerton, K J Williams, R.d. EsmanAbstract:An analog fiber-Optic Link for concurrent detection and downconversion of microwave signals is reported. Optical amplification is employed in conjunction with electrical power combining of photodetectors to demonstrate Link losses of 19.6 and 22.9 dB at RF carrier frequencies of 9 and 16 GHz, respectively. Analytic expressions validating the experimental observations are also developed. The Link may be employed to detect phase sensitive or phase-modulated microwave signals and shows excellent potential for application in sensor systems involving remoting of an antenna element. >
-
Stimulated Brillouin scattering for improvement of microwave fibre-Optic Link efficiency
1994Co-Authors: Keith J. Williams, R.d. EsmanAbstract:Stimulated Brillouin scattering is used to increase the modulation depth of a weakly-modulated Optical signal by rejecting the forward travelling carrier power. For an input power of eight times the stimulated Brillouin threshold, an improvement of 8 dB in Link loss from 0.1 to 20 GHz is achieved.