The accuracy of channel state information (CSI) is critical for improving the capacity of wireles... more The accuracy of channel state information (CSI) is critical for improving the capacity of wireless networks. In this paper, we introduce a training protocol for wireless relay networks that uses channel estimation and feedforwarding methods. The feedforwarding method is the distinctive feature of the proposed protocol. As we show, each relay feedforwards the imperfect CSI to the destination in a way that provides a higher network capacity and a faster transfer of the CSI than the existing protocols. In addition, we show the importance of the effective CSI accuracy on the wireless relay network capacity by comparing networks with the perfect effective CSI, imperfect effective CSI, and noisy imperfect effective CSI available at the destination.
2009 Australasian Universities Power Engineering Conference, 2009
ABSTRACT This research describes the monitoring of the fundamental spectral features of the beari... more ABSTRACT This research describes the monitoring of the fundamental spectral features of the bearing damage through accelerated aging studies for induction motors with a power rating of 5 HP. For this aim, the bearing damage is characterized between 2-4 kHz through the spectral analysis methods applied to motor vibration signals. Also, coherence analysis approach, defined between the stator currents and vibration signals, is used for as another indicator of the bearing damage. After the computation of the coherences, a neuro-detector based on the auto-associative neural structure is trained in the frequency domain. Hence, the bearing damage detection is realized by observing the changes in the errors (residuals) generated by the neural net.
Iee Proceedings G Circuits Devices and Systems, Dec 1, 1990
ABSTRACT A method, based on 2-D asymmetric half-plane lattice parameters, for the design of two d... more ABSTRACT A method, based on 2-D asymmetric half-plane lattice parameters, for the design of two dimensional (2-D) recursive digital filters is presented. The design procedure calculates the lattice parameter factors from the prescribed frequency characteristics. The order of the design is controlled by an a priori error criterion, corresponding to the minimum mean squared error between two successive stages. The stability of the resulting filter is determined at each successive lattice stage from the computed 2D reflection factors. The capabilities of the proposed approach are demonstrated by the design of a fan filter and circularly symmetric lowpass filter. The computer time for their design is of the order of seconds for both filters
IGARSS 2001. Scanning the Present and Resolving the Future. Proceedings. IEEE 2001 International Geoscience and Remote Sensing Symposium (Cat. No.01CH37217), 2000
Abstract An efficient algorithm to obtain high resolution ISAR images in the case of limited freq... more Abstract An efficient algorithm to obtain high resolution ISAR images in the case of limited frequency band and small angular section is presented. The method is based on the 2-D autoregressive asymmetric half-plane modeling of the backscattered data using a 2-D complex lattice predictor. The locations of the scattering centers are determined by the zeroes of the transfer function of the prediction error filter. A simulation example is included to show the performance of the algorithm
Proceedings of the IEEE 13th Signal Processing and Communications Applications Conference, 2005., 2005
Abstract A new procedure, where the original image and blur parameters can be simultaneously iden... more Abstract A new procedure, where the original image and blur parameters can be simultaneously identified using twodimensional (2-D) hybrid lattice structures has been presented, utilizing the fact that noisy and blurred images be presented by an ...
Developed approaches to spectral estimation can be grouped as parametric and non-parametric metho... more Developed approaches to spectral estimation can be grouped as parametric and non-parametric methods. Non- parametric methods are classical methods which are based on periodogram and they use Fourier transform. In this study, a parametric method is investigated. The two- dimensional orthogonal lattice structures are applied to spectrum estimation and the results are compared with the classical periodogram.
A new lattice filter structure is presented to model two-dimensional (2- D) autoregressive (AR) f... more A new lattice filter structure is presented to model two-dimensional (2- D) autoregressive (AR) fields. This work is the generalization of the three-parameter lattice filter developed by S. R. Parker and A. H. Kayran [IEEE Trans. Acoust. Speech Signal Process. ASSP-32, No.4, 872-885 (1984)]. The proposed structure generates four prediction error fields (one forward and three backward prediction error fields) at the first stage. After the first stage, using one of the backward prediction error fields, two additional prediction error fields are generated. This leads to six prediction error fields whose linear combination defines the successive lattice stages and the reflection coefficients. In addition, a recursive relationship between the reflection coefficients of the lattice filter and the AR coefficients is derived. This new structure and the three-parameter lattice filter are compared from information-theoretic point of view. It is concluded that the new structure approximates th...
In this study, the relation between the parameters of a quarter-plane causal 2-D ARMA process and... more In this study, the relation between the parameters of a quarter-plane causal 2-D ARMA process and their equivalent 2-D AR process is considered. Based on this relationship, a new algorithm is proposed for determining the 2-D ARMA model parameters from the coefficients of the 2-D equivalent AR model obtained by applying 2-D MYW equation to the process under consideration.
The accuracy of channel state information (CSI) is critical for improving the capacity of wireles... more The accuracy of channel state information (CSI) is critical for improving the capacity of wireless networks. In this paper, we introduce a training protocol for wireless relay networks that uses channel estimation and feedforwarding methods. The feedforwarding method is the distinctive feature of the proposed protocol. As we show, each relay feedforwards the imperfect CSI to the destination in a way that provides a higher network capacity and a faster transfer of the CSI than the existing protocols. In addition, we show the importance of the effective CSI accuracy on the wireless relay network capacity by comparing networks with the perfect effective CSI, imperfect effective CSI, and noisy imperfect effective CSI available at the destination.
2009 Australasian Universities Power Engineering Conference, 2009
ABSTRACT This research describes the monitoring of the fundamental spectral features of the beari... more ABSTRACT This research describes the monitoring of the fundamental spectral features of the bearing damage through accelerated aging studies for induction motors with a power rating of 5 HP. For this aim, the bearing damage is characterized between 2-4 kHz through the spectral analysis methods applied to motor vibration signals. Also, coherence analysis approach, defined between the stator currents and vibration signals, is used for as another indicator of the bearing damage. After the computation of the coherences, a neuro-detector based on the auto-associative neural structure is trained in the frequency domain. Hence, the bearing damage detection is realized by observing the changes in the errors (residuals) generated by the neural net.
Iee Proceedings G Circuits Devices and Systems, Dec 1, 1990
ABSTRACT A method, based on 2-D asymmetric half-plane lattice parameters, for the design of two d... more ABSTRACT A method, based on 2-D asymmetric half-plane lattice parameters, for the design of two dimensional (2-D) recursive digital filters is presented. The design procedure calculates the lattice parameter factors from the prescribed frequency characteristics. The order of the design is controlled by an a priori error criterion, corresponding to the minimum mean squared error between two successive stages. The stability of the resulting filter is determined at each successive lattice stage from the computed 2D reflection factors. The capabilities of the proposed approach are demonstrated by the design of a fan filter and circularly symmetric lowpass filter. The computer time for their design is of the order of seconds for both filters
IGARSS 2001. Scanning the Present and Resolving the Future. Proceedings. IEEE 2001 International Geoscience and Remote Sensing Symposium (Cat. No.01CH37217), 2000
Abstract An efficient algorithm to obtain high resolution ISAR images in the case of limited freq... more Abstract An efficient algorithm to obtain high resolution ISAR images in the case of limited frequency band and small angular section is presented. The method is based on the 2-D autoregressive asymmetric half-plane modeling of the backscattered data using a 2-D complex lattice predictor. The locations of the scattering centers are determined by the zeroes of the transfer function of the prediction error filter. A simulation example is included to show the performance of the algorithm
Proceedings of the IEEE 13th Signal Processing and Communications Applications Conference, 2005., 2005
Abstract A new procedure, where the original image and blur parameters can be simultaneously iden... more Abstract A new procedure, where the original image and blur parameters can be simultaneously identified using twodimensional (2-D) hybrid lattice structures has been presented, utilizing the fact that noisy and blurred images be presented by an ...
Developed approaches to spectral estimation can be grouped as parametric and non-parametric metho... more Developed approaches to spectral estimation can be grouped as parametric and non-parametric methods. Non- parametric methods are classical methods which are based on periodogram and they use Fourier transform. In this study, a parametric method is investigated. The two- dimensional orthogonal lattice structures are applied to spectrum estimation and the results are compared with the classical periodogram.
A new lattice filter structure is presented to model two-dimensional (2- D) autoregressive (AR) f... more A new lattice filter structure is presented to model two-dimensional (2- D) autoregressive (AR) fields. This work is the generalization of the three-parameter lattice filter developed by S. R. Parker and A. H. Kayran [IEEE Trans. Acoust. Speech Signal Process. ASSP-32, No.4, 872-885 (1984)]. The proposed structure generates four prediction error fields (one forward and three backward prediction error fields) at the first stage. After the first stage, using one of the backward prediction error fields, two additional prediction error fields are generated. This leads to six prediction error fields whose linear combination defines the successive lattice stages and the reflection coefficients. In addition, a recursive relationship between the reflection coefficients of the lattice filter and the AR coefficients is derived. This new structure and the three-parameter lattice filter are compared from information-theoretic point of view. It is concluded that the new structure approximates th...
In this study, the relation between the parameters of a quarter-plane causal 2-D ARMA process and... more In this study, the relation between the parameters of a quarter-plane causal 2-D ARMA process and their equivalent 2-D AR process is considered. Based on this relationship, a new algorithm is proposed for determining the 2-D ARMA model parameters from the coefficients of the 2-D equivalent AR model obtained by applying 2-D MYW equation to the process under consideration.
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Papers by Ahmet Hamdi Kayran