The Experts below are selected from a list of 20340 Experts worldwide ranked by ideXlab platform
Tobias Hidalgo Stitz - One of the best experts on this subject based on the ideXlab platform.
-
On the Use of Filter Bank Based Multicarrier Modulation for Professional Mobile Radio
2013 IEEE 77th Vehicular Technology Conference (VTC Spring), 2013Co-Authors: Markku Renfors, Faouzi Bader, Leonardo Baltar, Didier Le Ruyet, Daniel Roviras, Philippe Mege, Martin Haardt, Tobias Hidalgo StitzAbstract:Our main emphasis is on the use of enhanced OFDM and Filter Bank based multicarrier (FB-MC) waveforms for utilizing effectively the available fragmented spectrum in heterogeneous radio environments. Special attention is on the broadband-narrowband coexistence scenario of the Professional Mobile Radio (PMR) evolution. The target here is to provide broadband data services in coexistence with narrowband legacy services of the TETRA family. The core idea is a multi-mode radio platform, based on variable Filter Bank processing, which is able to perform modulation/detection functions simultaneously for different signal formats with adjustable center frequencies, bandwidths and subchannel spacings.
-
Spectrum monitoring scheme for Filter Bank based cognitive radios
2010 Future Network & Mobile Summit, 2010Co-Authors: Tero Ihalainen, Ari Viholainen, Tobias Hidalgo Stitz, Markku RenforsAbstract:This paper focuses on the spectrum monitoring problem, i.e., detecting reappearing primary users during secondary transmissions in cognitive radio systems. The Filter Bank multicarrier (FBMC) concept is used as the basis as it facilitates simultaneous spectrum sensing and reception of secondary transmissions using the same device. With FBMC it is possible to support, in a spectrally efficient manner, narrow subcarrier-wide gaps in the spectrum of the transmitted signal for monitoring purposes. Such scheme allows fast reaction to reappearing primary users and it needs minimum amount of coordination between independent secondary systems operating in the same frequency band. We analyze the effect of the Filter Bank frequency response on energy detection based spectrum sensing. We also evaluate the impact of spectral regrowth due to transmitter power amplifiers, which is a critical issue in the proposed scheme.
-
Prototype Filter design for Filter Bank based multicarrier transmission
2009 17th European Signal Processing Conference, 2009Co-Authors: Ari Viholainen, Markku Renfors, Tero Ihalainen, Tobias Hidalgo Stitz, Maurice BellangerAbstract:This paper concentrates on an efficient prototype Filter design in the context of Filter Bank based multicarrier (FBMC) transmission. An advantage of the chosen method, frequency sampling technique, is that near perfect reconstruction prototype Filters can be expressed using a closed-form representation with only a few adjustable parameters. The performance of various designs are analyzed using the offset-QAM based FBMC system. Numerical results are provided to characterize different optimization criteria in terms of frequency selectivity of resulting prototype Filters and total interference level of the Filter Bank structure. Furthermore, it is shown what kind of performance trade-offs can be obtained by adjusting those free parameters. In this sense, the presented results offer useful information to a system designer.
-
practical issues in frequency domain synchronization for Filter Bank based multicarrier transmission
International Symposium on Communications Control and Signal Processing, 2008Co-Authors: Tobias Hidalgo Stitz, Tero Ihalainen, Markku RenforsAbstract:In this paper we address the practical problems when dealing with synchronization and channel estimation in a Filter Bank based multicarrier system. We present an approach for performing timing synchronization, carrier frequency offset estimation and correction, and channel estimation based on the use of the same training sequences for all the three tasks. We show that it is possible to perform them all after the analysis Filter Bank at the receiver, at low sampling rate, taking advantage of the high selectivity of the subband Filters. The possibility to implement all the receiver baseband signal processing functionalities in frequency domain results in a very flexible overall receiver architecture, suitable for dynamic use of the frequency spectrum.
-
channel equalization in Filter Bank based multicarrier modulation for wireless communications
EURASIP Journal on Advances in Signal Processing, 2007Co-Authors: Tero Ihalainen, Tobias Hidalgo Stitz, Mika Rinne, Markku RenforsAbstract:Channel equalization in Filter Bank based multicarrier (FBMC) modulation is addressed. We utilize an efficient oversampled Filter Bank concept with 2x-oversampled subcarrier signals that can be equalized independently of each other. Due to Nyquist pulse shaping, consecutive symbol waveforms overlap in time, which calls for special means for equalization. Two alternative linear low-complexity subcarrier equalizer structures are developed together with straightforward channel estimation-based methods to calculate the equalizer coefficients using pointwise equalization within each subband (in a frequency-sampled manner). A novel structure, consisting of a linear-phase FIR amplitude equalizer and an allpass Filter as phase equalizer, is found to provide enhanced robustness to timing estimation errors. This allows the receiver to be operated without time synchronization before the Filter Bank. The coded error-rate performance of FBMC with the studied equalization scheme is compared to a cyclic prefix OFDM reference in wireless mobile channel conditions, taking into account issues like spectral regrowth with practical nonlinear transmitters and sensitivity to frequency offsets. It is further emphasized that FBMC provides flexible means for high-quality frequency selective Filtering in the receiver to suppress strong interfering spectral components within or close to the used frequency band.
Markku Renfors - One of the best experts on this subject based on the ideXlab platform.
-
On the Use of Filter Bank Based Multicarrier Modulation for Professional Mobile Radio
2013 IEEE 77th Vehicular Technology Conference (VTC Spring), 2013Co-Authors: Markku Renfors, Faouzi Bader, Leonardo Baltar, Didier Le Ruyet, Daniel Roviras, Philippe Mege, Martin Haardt, Tobias Hidalgo StitzAbstract:Our main emphasis is on the use of enhanced OFDM and Filter Bank based multicarrier (FB-MC) waveforms for utilizing effectively the available fragmented spectrum in heterogeneous radio environments. Special attention is on the broadband-narrowband coexistence scenario of the Professional Mobile Radio (PMR) evolution. The target here is to provide broadband data services in coexistence with narrowband legacy services of the TETRA family. The core idea is a multi-mode radio platform, based on variable Filter Bank processing, which is able to perform modulation/detection functions simultaneously for different signal formats with adjustable center frequencies, bandwidths and subchannel spacings.
-
Spectrum monitoring scheme for Filter Bank based cognitive radios
2010 Future Network & Mobile Summit, 2010Co-Authors: Tero Ihalainen, Ari Viholainen, Tobias Hidalgo Stitz, Markku RenforsAbstract:This paper focuses on the spectrum monitoring problem, i.e., detecting reappearing primary users during secondary transmissions in cognitive radio systems. The Filter Bank multicarrier (FBMC) concept is used as the basis as it facilitates simultaneous spectrum sensing and reception of secondary transmissions using the same device. With FBMC it is possible to support, in a spectrally efficient manner, narrow subcarrier-wide gaps in the spectrum of the transmitted signal for monitoring purposes. Such scheme allows fast reaction to reappearing primary users and it needs minimum amount of coordination between independent secondary systems operating in the same frequency band. We analyze the effect of the Filter Bank frequency response on energy detection based spectrum sensing. We also evaluate the impact of spectral regrowth due to transmitter power amplifiers, which is a critical issue in the proposed scheme.
-
Prototype Filter design for Filter Bank based multicarrier transmission
2009 17th European Signal Processing Conference, 2009Co-Authors: Ari Viholainen, Markku Renfors, Tero Ihalainen, Tobias Hidalgo Stitz, Maurice BellangerAbstract:This paper concentrates on an efficient prototype Filter design in the context of Filter Bank based multicarrier (FBMC) transmission. An advantage of the chosen method, frequency sampling technique, is that near perfect reconstruction prototype Filters can be expressed using a closed-form representation with only a few adjustable parameters. The performance of various designs are analyzed using the offset-QAM based FBMC system. Numerical results are provided to characterize different optimization criteria in terms of frequency selectivity of resulting prototype Filters and total interference level of the Filter Bank structure. Furthermore, it is shown what kind of performance trade-offs can be obtained by adjusting those free parameters. In this sense, the presented results offer useful information to a system designer.
-
practical issues in frequency domain synchronization for Filter Bank based multicarrier transmission
International Symposium on Communications Control and Signal Processing, 2008Co-Authors: Tobias Hidalgo Stitz, Tero Ihalainen, Markku RenforsAbstract:In this paper we address the practical problems when dealing with synchronization and channel estimation in a Filter Bank based multicarrier system. We present an approach for performing timing synchronization, carrier frequency offset estimation and correction, and channel estimation based on the use of the same training sequences for all the three tasks. We show that it is possible to perform them all after the analysis Filter Bank at the receiver, at low sampling rate, taking advantage of the high selectivity of the subband Filters. The possibility to implement all the receiver baseband signal processing functionalities in frequency domain results in a very flexible overall receiver architecture, suitable for dynamic use of the frequency spectrum.
-
channel equalization in Filter Bank based multicarrier modulation for wireless communications
EURASIP Journal on Advances in Signal Processing, 2007Co-Authors: Tero Ihalainen, Tobias Hidalgo Stitz, Mika Rinne, Markku RenforsAbstract:Channel equalization in Filter Bank based multicarrier (FBMC) modulation is addressed. We utilize an efficient oversampled Filter Bank concept with 2x-oversampled subcarrier signals that can be equalized independently of each other. Due to Nyquist pulse shaping, consecutive symbol waveforms overlap in time, which calls for special means for equalization. Two alternative linear low-complexity subcarrier equalizer structures are developed together with straightforward channel estimation-based methods to calculate the equalizer coefficients using pointwise equalization within each subband (in a frequency-sampled manner). A novel structure, consisting of a linear-phase FIR amplitude equalizer and an allpass Filter as phase equalizer, is found to provide enhanced robustness to timing estimation errors. This allows the receiver to be operated without time synchronization before the Filter Bank. The coded error-rate performance of FBMC with the studied equalization scheme is compared to a cyclic prefix OFDM reference in wireless mobile channel conditions, taking into account issues like spectral regrowth with practical nonlinear transmitters and sensitivity to frequency offsets. It is further emphasized that FBMC provides flexible means for high-quality frequency selective Filtering in the receiver to suppress strong interfering spectral components within or close to the used frequency band.
Ying Wei - One of the best experts on this subject based on the ideXlab platform.
-
design of low complexity adjustable Filter Bank for personalized hearing aid solutions
IEEE Transactions on Audio Speech and Language Processing, 2015Co-Authors: Ying Wei, Yinfeng WangAbstract:The emerging demand for personalized hearing aids requires the Filter Bank of a hearing aid system to be capable of decomposing the sound waves in accordance with the characteristic of the patient’s hearing loss. In this paper, an efficient adjustable Filter Bank is proposed to achieve this goal. By careful design, the number of the subbands as well as the location of the subbands can be easily adjusted by changing a 4-bit control signal. The proposed Filter Bank has extremely low complexity due to the adoption of fractional interpolation and the technique of symmetric and complementary Filters. Only one prototype Filter is needed for each of the stages, the multiple passbands generation stage and masking stage. We show, by means of examples, that the proposed Filter Bank can meet different needs of hearing loss cases with acceptable delay.
-
a computationally efficient nonuniform fir digital Filter Bank for hearing aids
IEEE Transactions on Circuits and Systems, 2005Co-Authors: Yong Lian, Ying WeiAbstract:A computationally efficient nonuniform digital FIR Filter Bank is proposed for hearing aid applications. The eight nonuniform spaced subbands are formed with the help of frequency-response masking technique. Two half-band finite-impulse response (FIR) Filters are employed as prototypes resulting in significant improvements in the computational efficiency. We show, by means of example, that an eight-band nonuniform FIR Filter Bank with stopband attenuation of 80 dB can be implemented with 15 multipliers. The performance of the Filter Bank is enhanced by optimizing the gains for each subband. The tests on various hearing loss cases suggest that the proposed Filter achieves reasonable good matching between audiograms and magnitude responses of the Filter Bank at very low computational cost.
-
a computationally efficient non uniform digital fir Filter Bank for hearing aid
IEEE International Workshop on Biomedical Circuits and Systems, 2004Co-Authors: Ying Wei, Yong LianAbstract:A computationally efficient non-uniform digital FIR Filter Bank is proposed for hearing aid applications. The ten non-uniform sub-bands are formed with the help of frequency masking technique. Two half-band Filters are employed as prototypes resulting in significant improvements in the computational efficiency. The example shows that the proposed Filter Bank with stopband attenuation of 40dB can be implemented with 14 multipliers and matches the hearing audiograms with less than +/-5dB errors.
Masaaki Ikehara - One of the best experts on this subject based on the ideXlab platform.
-
decorrelating compensation scheme for coefficient errors of a Filter Bank parallel a d converter
IEEE Transactions on Wireless Communications, 2004Co-Authors: Yukitoshi Sanada, Masaaki IkeharaAbstract:In this letter, a parallel analog-digital (A/D) conversion scheme with a Filter Bank for low intermediate-frequency receivers is presented. The analysis Filters of the Filter Bank divide the frequency components of the received signal, and achieve parallel A/D conversion. Therefore, the required conversion rates and the resolution of the A/D converters can be reduced and the receiver can demodulate wideband signals. As the analysis Filters consist of analog components, their coefficients include errors. These errors cause mutual interference between signals in orthogonal frequencies. In order to remove this interference, a decorrelating compensation scheme is proposed.
-
decorrelating compensation scheme for coefficient errors of a Filter Bank parallel a d converter
Vehicular Technology Conference, 2002Co-Authors: Yukitoshi Sanada, Masaaki IkeharaAbstract:A parallel A/D conversion scheme with a Filter Bank for low-IF receivers is presented. The analysis Filters of the Filter Bank divide the frequency components of the received signal, and achieve parallel A/D conversion. Therefore, the required conversion rates and the resolution of the A/D converters can be reduced and the receiver can demodulate wideband signals. As the analysis Filters consist of analog components, their coefficients include errors. These errors cause mutual interference between signals in orthogonal frequencies. In order to remove this interference, a decorrelating compensation scheme is proposed.
Maurice Bellanger - One of the best experts on this subject based on the ideXlab platform.
-
Prototype Filter design for Filter Bank based multicarrier transmission
2009 17th European Signal Processing Conference, 2009Co-Authors: Ari Viholainen, Markku Renfors, Tero Ihalainen, Tobias Hidalgo Stitz, Maurice BellangerAbstract:This paper concentrates on an efficient prototype Filter design in the context of Filter Bank based multicarrier (FBMC) transmission. An advantage of the chosen method, frequency sampling technique, is that near perfect reconstruction prototype Filters can be expressed using a closed-form representation with only a few adjustable parameters. The performance of various designs are analyzed using the offset-QAM based FBMC system. Numerical results are provided to characterize different optimization criteria in terms of frequency selectivity of resulting prototype Filters and total interference level of the Filter Bank structure. Furthermore, it is shown what kind of performance trade-offs can be obtained by adjusting those free parameters. In this sense, the presented results offer useful information to a system designer.
