quadrature amplitude modulation

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Gustavo Rodriguez-zurita - One of the best experts on this subject based on the ideXlab platform.

  • One-shot phase-visibility modulating interferometry by on–off non-quadrature amplitude modulation
    Optics and Lasers in Engineering, 2014
    Co-Authors: Cruz Meneses-fabian, Uriel Rivera-ortega, Gustavo Rodriguez-zurita
    Abstract:

    Abstract This manuscript presents a proposal for achieving in a single-shot the phase-visibility modulating interferometry method. The setup is based on a 4f optical system consisting of three apertures at the input plane and a grid with a fill factor of 1/2 at the Fourier plane. One of the apertures serves as a probe beam and the other two apertures serve as reference beams, with which a reference beam modulated in phase and amplitude by the on–off non-quadrature amplitude modulation method is created. We show that the grid implements simultaneously the on–off non-quadrature amplitude modulation technique; therefore multiple interferograms can be obtained in a single-shot. A theoretical model will be shown supported by the experimental results.

  • Inhomogeneous phase-visibility modulating interferometry by space on-off non-quadrature amplitude modulation
    Optics express, 2013
    Co-Authors: Uriel Rivera-ortega, Cruz Meneses-fabian, Gustavo Rodriguez-zurita
    Abstract:

    A new method in interferometry based on on-off non-quadrature amplitude modulation for object phase retrieval is presented. Although the technique introduces inhomogeneous visibility and phase variations in the interferogram, it is shown that the phase retrieval of a given object is still possible. This method is implemented by using three beams and two Mach-Zehnder interferometers in series. One of the arms of the system is used as a probe beam and the other two are used as reference beams, yielding from their sum the conventional reference beam of a two-beam interferometer. We demonstrate that, if there is a phase difference within the range of (0,π) between these two beams, the effect of modulation in both amplitude and phase is generated for the case of on-off non-quadrature amplitude modulation. An analytical discussion is provided to sustain this method. Numerical and experimental results are also shown.

Lajos Hanzo - One of the best experts on this subject based on the ideXlab platform.

  • Differential evolution algorithm aided MBER beamforming receiver for quadrature amplitude modulation systems
    2011
    Co-Authors: Jian-kang Zhang, S. Chen, Lajos Hanzo
    Abstract:

    Evolutionary computational intelligence methods have found wide-ranging application in communication and other walks of engineering. The main attraction of adopting evolutionary computational intelligence algorithms is that they may facilitate global or near global optimal designs with affordable computational costs. This contribution considers the beamforming assisted multiple-antenna receiver for multi-user quadrature amplitude modulation systems. The bit error rate (BER) expression as the function of the beamformer's weight vector is derived explicitly. The minimum BER (MBER) beamforming receiver can then be obtained as the solution of the resulting optimisation problem that minimises the MBER criterion. We propose to employ a differential evolution algorithm to solve the MBER optimisation by its virtue of computational efficiency and ability to locate a global minimum quickly.

  • Semi-blind adaptive beamforming for high-throughput quadrature amplitude modulation systems
    International Journal of Automation and Computing, 2010
    Co-Authors: S. Chen, Wang Yao, Lajos Hanzo
    Abstract:

    A semi-blind adaptive beamforming scheme is proposed for wireless systems that employ high-throughput quadrature amplitude modulation signalling. A minimum number of training symbols, equal to the number of receiver antenna array's elements, are first utilised to provide a rough initial least squares estimate of the beamformer's weight vector. A concurrent constant modulus algorithm and soft decision-directed scheme is then applied to adapt the beamformer. This semi-blind adaptive beamforming scheme is capable of converging fast to the minimum mean-square-error beamforming solution, as demonstrated in our simulation study.

  • adaptive minimum symbol error rate beamforming assisted detection for quadrature amplitude modulation
    IEEE Transactions on Wireless Communications, 2008
    Co-Authors: S. Chen, A Livingstone, H Q Du, Lajos Hanzo
    Abstract:

    We consider beamforming assisted detection for multiple antenna aided multiuser systems that employ the bandwidth efficient quadrature amplitude modulation scheme. A minimum symbol error rate (MSER) design is proposed for the beamforming assisted receiver, and it is shown that this MSER design provides significant performance enhancement, in terms of achievable symbol error rate, over the standard minimum mean square error (MMSE) design. A sample-by-sample adaptive algorithm, referred to as the least symbol error rate, is derived for adaptive implementation of the MSER beamforming solution. The proposed adaptive MSER scheme is evaluated in simulation using Rayleigh fading channels, in comparison with the adaptive MMSE benchmarker.

  • ICC - Semi-Blind Spatial Equalisation for MIMO Channels with quadrature amplitude modulation
    2008 IEEE International Conference on Communications, 2008
    Co-Authors: S. Chen, Lajos Hanzo, Wang Yao
    Abstract:

    Semi-blind spatial equalisation is considered for multiple-input multiple-output (MIMO) systems that employ high-throughput quadrature amplitude modulation scheme. A minimum number of training symbols, equal to the number of transmitters, are first utilised to provide a rough least squares channel estimate of the system's MIMO channel matrix for the initialisation of the spatial equalisers' weight vectors. A constant modulus algorithm aided soft decision-directed blind algorithm is then employed to adapt the spatial equalisers. This semi- blind scheme has a very-low computational complexity, and it converges fast to the minimum mean-square-error spatial equalisation solution as demonstrated in our simulation study.

S. Chen - One of the best experts on this subject based on the ideXlab platform.

  • Differential evolution algorithm aided MBER beamforming receiver for quadrature amplitude modulation systems
    2011
    Co-Authors: Jian-kang Zhang, S. Chen, Lajos Hanzo
    Abstract:

    Evolutionary computational intelligence methods have found wide-ranging application in communication and other walks of engineering. The main attraction of adopting evolutionary computational intelligence algorithms is that they may facilitate global or near global optimal designs with affordable computational costs. This contribution considers the beamforming assisted multiple-antenna receiver for multi-user quadrature amplitude modulation systems. The bit error rate (BER) expression as the function of the beamformer's weight vector is derived explicitly. The minimum BER (MBER) beamforming receiver can then be obtained as the solution of the resulting optimisation problem that minimises the MBER criterion. We propose to employ a differential evolution algorithm to solve the MBER optimisation by its virtue of computational efficiency and ability to locate a global minimum quickly.

  • Semi-blind adaptive beamforming for high-throughput quadrature amplitude modulation systems
    International Journal of Automation and Computing, 2010
    Co-Authors: S. Chen, Wang Yao, Lajos Hanzo
    Abstract:

    A semi-blind adaptive beamforming scheme is proposed for wireless systems that employ high-throughput quadrature amplitude modulation signalling. A minimum number of training symbols, equal to the number of receiver antenna array's elements, are first utilised to provide a rough initial least squares estimate of the beamformer's weight vector. A concurrent constant modulus algorithm and soft decision-directed scheme is then applied to adapt the beamformer. This semi-blind adaptive beamforming scheme is capable of converging fast to the minimum mean-square-error beamforming solution, as demonstrated in our simulation study.

  • adaptive minimum symbol error rate beamforming assisted detection for quadrature amplitude modulation
    IEEE Transactions on Wireless Communications, 2008
    Co-Authors: S. Chen, A Livingstone, H Q Du, Lajos Hanzo
    Abstract:

    We consider beamforming assisted detection for multiple antenna aided multiuser systems that employ the bandwidth efficient quadrature amplitude modulation scheme. A minimum symbol error rate (MSER) design is proposed for the beamforming assisted receiver, and it is shown that this MSER design provides significant performance enhancement, in terms of achievable symbol error rate, over the standard minimum mean square error (MMSE) design. A sample-by-sample adaptive algorithm, referred to as the least symbol error rate, is derived for adaptive implementation of the MSER beamforming solution. The proposed adaptive MSER scheme is evaluated in simulation using Rayleigh fading channels, in comparison with the adaptive MMSE benchmarker.

  • ICC - Semi-Blind Spatial Equalisation for MIMO Channels with quadrature amplitude modulation
    2008 IEEE International Conference on Communications, 2008
    Co-Authors: S. Chen, Lajos Hanzo, Wang Yao
    Abstract:

    Semi-blind spatial equalisation is considered for multiple-input multiple-output (MIMO) systems that employ high-throughput quadrature amplitude modulation scheme. A minimum number of training symbols, equal to the number of transmitters, are first utilised to provide a rough least squares channel estimate of the system's MIMO channel matrix for the initialisation of the spatial equalisers' weight vectors. A constant modulus algorithm aided soft decision-directed blind algorithm is then employed to adapt the spatial equalisers. This semi- blind scheme has a very-low computational complexity, and it converges fast to the minimum mean-square-error spatial equalisation solution as demonstrated in our simulation study.

Uriel Rivera-ortega - One of the best experts on this subject based on the ideXlab platform.

  • One-shot phase-visibility modulating interferometry by on–off non-quadrature amplitude modulation
    Optics and Lasers in Engineering, 2014
    Co-Authors: Cruz Meneses-fabian, Uriel Rivera-ortega, Gustavo Rodriguez-zurita
    Abstract:

    Abstract This manuscript presents a proposal for achieving in a single-shot the phase-visibility modulating interferometry method. The setup is based on a 4f optical system consisting of three apertures at the input plane and a grid with a fill factor of 1/2 at the Fourier plane. One of the apertures serves as a probe beam and the other two apertures serve as reference beams, with which a reference beam modulated in phase and amplitude by the on–off non-quadrature amplitude modulation method is created. We show that the grid implements simultaneously the on–off non-quadrature amplitude modulation technique; therefore multiple interferograms can be obtained in a single-shot. A theoretical model will be shown supported by the experimental results.

  • Homogeneous polarized light by non-quadrature amplitude modulation
    Optics and Lasers in Engineering, 2014
    Co-Authors: Cruz Meneses-fabian, Rosaura Kantun-montiel, Gildardo-pablo Lemus-alonso, Uriel Rivera-ortega
    Abstract:

    Abstract A method to create homogenous polarized light based on non-quadrature amplitude modulation is proposed. This method consists of the addition of two optical fields out of phase, different from m π and in the variation of their amplitudes, only for obtaining a resulting field modulated in both phase and amplitude. This principle is used to modulate the vertical components in both phase and amplitude, while the horizontal component is varied in amplitude but with a constant phase. Thus, any amplitude relation and phase difference between components can be created, and therefore any polarization state could be obtained. A theoretical model is shown and supported with numerical simulations of several polarization examples.

  • Polarized light by quadrature amplitude modulation
    8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics Lasers and Applications, 2013
    Co-Authors: Rosaura Kantun-montiel, Cruz Meneses-fabian, Uriel Rivera-ortega, Gildardo-pablo Lemus-alonso, Erika Barojas-gutierrez, Rosario Pastrana-sanchez
    Abstract:

    A new method to create elliptically polarized light based on the quadrature amplitude modulation is proposed. This method begins from an unpolarized light and does not use any classical methods, as for instance those using polarizers and retarders or also by refraction, scattering, dichroism or birefringence effects. This method is based on the amplitude modulation of two optical waves in quadrature in order to modulate the field in amplitude and phase. With this idea, we show that any amplitude relation and relative phase difference between components can be created and therefore any polarization state can be carried out. A theoretical model will be shown, and it will be sustained with numerical simulations of several polarization examples

  • Homogeneous polarized light by non-quadrature amplitude modulation
    8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics Lasers and Applications, 2013
    Co-Authors: Gildardo-pablo Lemus-alonso, Rosaura Kantun-montiel, Cruz Meneses-fabian, Uriel Rivera-ortega, Francisco Alejandro Lara-cortes, Rigoberto Juarez-salazar, Carlos Robledo-sanchez
    Abstract:

    A method to create homogenous polarized light based on non-quadrature amplitude modulation is proposed. This method consists in the addition of two fields out of phase different from mπ and in the variation of their amplitudes only for obtaining a resulting field modulated in both phase and amplitude. This principle is used to modulate the vertical component in both phase and amplitude, while the horizontal component is varied in amplitude only keeping constant its phase, thus any amplitude relation and phase difference between components can be created and therefore any polarization state could be obtained. A theoretical model will be shown, and it will be sustained with numerical simulations of several polarization examples.

  • Inhomogeneous phase-visibility modulating interferometry by space on-off non-quadrature amplitude modulation
    Optics express, 2013
    Co-Authors: Uriel Rivera-ortega, Cruz Meneses-fabian, Gustavo Rodriguez-zurita
    Abstract:

    A new method in interferometry based on on-off non-quadrature amplitude modulation for object phase retrieval is presented. Although the technique introduces inhomogeneous visibility and phase variations in the interferogram, it is shown that the phase retrieval of a given object is still possible. This method is implemented by using three beams and two Mach-Zehnder interferometers in series. One of the arms of the system is used as a probe beam and the other two are used as reference beams, yielding from their sum the conventional reference beam of a two-beam interferometer. We demonstrate that, if there is a phase difference within the range of (0,π) between these two beams, the effect of modulation in both amplitude and phase is generated for the case of on-off non-quadrature amplitude modulation. An analytical discussion is provided to sustain this method. Numerical and experimental results are also shown.

Cruz Meneses-fabian - One of the best experts on this subject based on the ideXlab platform.

  • One-shot phase-visibility modulating interferometry by on–off non-quadrature amplitude modulation
    Optics and Lasers in Engineering, 2014
    Co-Authors: Cruz Meneses-fabian, Uriel Rivera-ortega, Gustavo Rodriguez-zurita
    Abstract:

    Abstract This manuscript presents a proposal for achieving in a single-shot the phase-visibility modulating interferometry method. The setup is based on a 4f optical system consisting of three apertures at the input plane and a grid with a fill factor of 1/2 at the Fourier plane. One of the apertures serves as a probe beam and the other two apertures serve as reference beams, with which a reference beam modulated in phase and amplitude by the on–off non-quadrature amplitude modulation method is created. We show that the grid implements simultaneously the on–off non-quadrature amplitude modulation technique; therefore multiple interferograms can be obtained in a single-shot. A theoretical model will be shown supported by the experimental results.

  • Homogeneous polarized light by non-quadrature amplitude modulation
    Optics and Lasers in Engineering, 2014
    Co-Authors: Cruz Meneses-fabian, Rosaura Kantun-montiel, Gildardo-pablo Lemus-alonso, Uriel Rivera-ortega
    Abstract:

    Abstract A method to create homogenous polarized light based on non-quadrature amplitude modulation is proposed. This method consists of the addition of two optical fields out of phase, different from m π and in the variation of their amplitudes, only for obtaining a resulting field modulated in both phase and amplitude. This principle is used to modulate the vertical components in both phase and amplitude, while the horizontal component is varied in amplitude but with a constant phase. Thus, any amplitude relation and phase difference between components can be created, and therefore any polarization state could be obtained. A theoretical model is shown and supported with numerical simulations of several polarization examples.

  • Polarized light by quadrature amplitude modulation
    8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics Lasers and Applications, 2013
    Co-Authors: Rosaura Kantun-montiel, Cruz Meneses-fabian, Uriel Rivera-ortega, Gildardo-pablo Lemus-alonso, Erika Barojas-gutierrez, Rosario Pastrana-sanchez
    Abstract:

    A new method to create elliptically polarized light based on the quadrature amplitude modulation is proposed. This method begins from an unpolarized light and does not use any classical methods, as for instance those using polarizers and retarders or also by refraction, scattering, dichroism or birefringence effects. This method is based on the amplitude modulation of two optical waves in quadrature in order to modulate the field in amplitude and phase. With this idea, we show that any amplitude relation and relative phase difference between components can be created and therefore any polarization state can be carried out. A theoretical model will be shown, and it will be sustained with numerical simulations of several polarization examples

  • Homogeneous polarized light by non-quadrature amplitude modulation
    8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics Lasers and Applications, 2013
    Co-Authors: Gildardo-pablo Lemus-alonso, Rosaura Kantun-montiel, Cruz Meneses-fabian, Uriel Rivera-ortega, Francisco Alejandro Lara-cortes, Rigoberto Juarez-salazar, Carlos Robledo-sanchez
    Abstract:

    A method to create homogenous polarized light based on non-quadrature amplitude modulation is proposed. This method consists in the addition of two fields out of phase different from mπ and in the variation of their amplitudes only for obtaining a resulting field modulated in both phase and amplitude. This principle is used to modulate the vertical component in both phase and amplitude, while the horizontal component is varied in amplitude only keeping constant its phase, thus any amplitude relation and phase difference between components can be created and therefore any polarization state could be obtained. A theoretical model will be shown, and it will be sustained with numerical simulations of several polarization examples.

  • Inhomogeneous phase-visibility modulating interferometry by space on-off non-quadrature amplitude modulation
    Optics express, 2013
    Co-Authors: Uriel Rivera-ortega, Cruz Meneses-fabian, Gustavo Rodriguez-zurita
    Abstract:

    A new method in interferometry based on on-off non-quadrature amplitude modulation for object phase retrieval is presented. Although the technique introduces inhomogeneous visibility and phase variations in the interferogram, it is shown that the phase retrieval of a given object is still possible. This method is implemented by using three beams and two Mach-Zehnder interferometers in series. One of the arms of the system is used as a probe beam and the other two are used as reference beams, yielding from their sum the conventional reference beam of a two-beam interferometer. We demonstrate that, if there is a phase difference within the range of (0,π) between these two beams, the effect of modulation in both amplitude and phase is generated for the case of on-off non-quadrature amplitude modulation. An analytical discussion is provided to sustain this method. Numerical and experimental results are also shown.

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