The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Minghsu Chuang - One of the best experts on this subject based on the ideXlab platform.
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10 ms 18 band quasi ansi s1 11 1 3 octave filter bank for digital hearing aids
IEEE Transactions on Circuits and Systems, 2013Co-Authors: Chihwei Liu, Kuochiang Chang, Minghsu ChuangAbstract:The ANSI S1.11 1/3-octave filter bank is suitable for digital hearing aids, but its large group delay and high computational complexity complicate matters considerably. This study presents a 10-ms 18-band quasi-ANSI S1.11 1/3-octave filter bank for processing 24 kHz audio signals. We first discuss a filter order optimization algorithm to define the quasi-ANSI filters. The group delay constraint of filters is limited to 10 ms. The proposed design adopts an efficient prescription-fitting algorithm to reduce inter-band interference, enabling the proposed quasi-ANSI filter bank to compensate any type of hearing loss (HL) using the NAL-NL1 or HSE prescription formulas. Simulation results reveal that the maximum matching error in the prescriptions of the mild HL, moderate HL, and severe-to-profound HL is less than 1.5 dB. This study also investigates the complexity-effective multirate IFIR quasi-ANSI filter bank. For an 18-band digital hearing aid with a 24 kHz sampling rate, the proposed architecture eliminates approximately 93% of the multiplications and up to 74% of the storage elements, compared with a parallel FIR filters architecture. The proposed analysis filter bank (AFB) was designed in UMC 90 nm CMOS high-VT technology, and on the basis of post-layout simulations, it consumes 73 μW (@VDD=1 V). By voltage scaling (to 0.6 V), the simulation results show that the power consumption decreases to 27 μW, which is approximately 30% of that consumed by the most energy-efficient AFB available in the literature for use in hearing aids.
Chihwei Liu - One of the best experts on this subject based on the ideXlab platform.
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10 ms 18 band quasi ansi s1 11 1 3 octave filter bank for digital hearing aids
IEEE Transactions on Circuits and Systems, 2013Co-Authors: Chihwei Liu, Kuochiang Chang, Minghsu ChuangAbstract:The ANSI S1.11 1/3-octave filter bank is suitable for digital hearing aids, but its large group delay and high computational complexity complicate matters considerably. This study presents a 10-ms 18-band quasi-ANSI S1.11 1/3-octave filter bank for processing 24 kHz audio signals. We first discuss a filter order optimization algorithm to define the quasi-ANSI filters. The group delay constraint of filters is limited to 10 ms. The proposed design adopts an efficient prescription-fitting algorithm to reduce inter-band interference, enabling the proposed quasi-ANSI filter bank to compensate any type of hearing loss (HL) using the NAL-NL1 or HSE prescription formulas. Simulation results reveal that the maximum matching error in the prescriptions of the mild HL, moderate HL, and severe-to-profound HL is less than 1.5 dB. This study also investigates the complexity-effective multirate IFIR quasi-ANSI filter bank. For an 18-band digital hearing aid with a 24 kHz sampling rate, the proposed architecture eliminates approximately 93% of the multiplications and up to 74% of the storage elements, compared with a parallel FIR filters architecture. The proposed analysis filter bank (AFB) was designed in UMC 90 nm CMOS high-VT technology, and on the basis of post-layout simulations, it consumes 73 μW (@VDD=1 V). By voltage scaling (to 0.6 V), the simulation results show that the power consumption decreases to 27 μW, which is approximately 30% of that consumed by the most energy-efficient AFB available in the literature for use in hearing aids.
Kuochiang Chang - One of the best experts on this subject based on the ideXlab platform.
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10 ms 18 band quasi ansi s1 11 1 3 octave filter bank for digital hearing aids
IEEE Transactions on Circuits and Systems, 2013Co-Authors: Chihwei Liu, Kuochiang Chang, Minghsu ChuangAbstract:The ANSI S1.11 1/3-octave filter bank is suitable for digital hearing aids, but its large group delay and high computational complexity complicate matters considerably. This study presents a 10-ms 18-band quasi-ANSI S1.11 1/3-octave filter bank for processing 24 kHz audio signals. We first discuss a filter order optimization algorithm to define the quasi-ANSI filters. The group delay constraint of filters is limited to 10 ms. The proposed design adopts an efficient prescription-fitting algorithm to reduce inter-band interference, enabling the proposed quasi-ANSI filter bank to compensate any type of hearing loss (HL) using the NAL-NL1 or HSE prescription formulas. Simulation results reveal that the maximum matching error in the prescriptions of the mild HL, moderate HL, and severe-to-profound HL is less than 1.5 dB. This study also investigates the complexity-effective multirate IFIR quasi-ANSI filter bank. For an 18-band digital hearing aid with a 24 kHz sampling rate, the proposed architecture eliminates approximately 93% of the multiplications and up to 74% of the storage elements, compared with a parallel FIR filters architecture. The proposed analysis filter bank (AFB) was designed in UMC 90 nm CMOS high-VT technology, and on the basis of post-layout simulations, it consumes 73 μW (@VDD=1 V). By voltage scaling (to 0.6 V), the simulation results show that the power consumption decreases to 27 μW, which is approximately 30% of that consumed by the most energy-efficient AFB available in the literature for use in hearing aids.
Duncan A. Robertson - One of the best experts on this subject based on the ideXlab platform.
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Radar micro-Doppler signatures of drones and birds at K-Band and W-band
Scientific Reports, 2018Co-Authors: Samiur Rahman, Duncan A. RobertsonAbstract:Due to the substantial increase in the number of affordable drones in the consumer market and their regrettable misuse, there is a need for efficient technology to detect drones in airspace. This paper presents the characteristic radar micro-Doppler properties of drones and birds. Drones and birds both induce micro-Doppler signatures due to their propeller blade rotation and wingbeats, respectively. These distinctive signatures can then be used to differentiate a drone from a bird, along with studying them separately. Here, experimental measurements of micro-Doppler signatures of different types of drones and birds are presented and discussed. The data have been collected using two radars operating at different frequencies; K-Band (24 GHz) and W-band (94 GHz). Three different models of drones and four species of birds of varying sizes have been used for data collection. The results clearly demonstrate that a phase coherent radar system can retrieve highly reliable and distinctive micro-Doppler signatures of these flying targets, both at K-Band and W-band. Comparison of the signatures obtained at the two frequencies indicates that the micro-Doppler return from the W-band radar has higher SNR. However, micro-Doppler features in the K-Band radar returns also reveal the micro-motion characteristics of drones and birds very effectively.
Jacques Oksman - One of the best experts on this subject based on the ideXlab platform.
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Wide-band, band-pass and versatile Hybrid Filter Bank A/D conversion for software radio
IEEE Circuits and Systems Magazine, 2009Co-Authors: Caroline Lelandais-perrault, Daniel Poulton, Pierre Duhamel, Tudor Petrescu, Jacques OksmanAbstract:This paper deals with analog-to-digital (A/D) conversion for future software/cognitive radio systems. For these applications, A/D converters should convert wideband signals and offer high resolutions. In order to achieve this and to overcome technological limitations, the A/D conversion systems should be versatile, i.e. it should be possible to adapt the conversion characteristics (resolution and bandwidth) by software. This work studies and adapts Hybrid Filter Banks (HFBs) in this context. First, HFBs, which can provide large conversion bandwidth, are extended to band-pass sampling, thus minimizing the sampling frequency. Then, we provide efficient ways of improving the HFB resolution in a smaller frequency band, only by reprogramming the digital part. Moreover, this study takes into account the main drawback of HFBs which is their very high sensitivity to analog imperfections. Simulation results are presented to demonstrate the performance of HFBs.
