Zhi Guo Feng

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In this paper, we consider the optimal design of finite-impulse response (FIR) filters with coefficients expressed as sums of signed powers-of-two (SPT) terms, where the normalized peak ripple (NPR) is taken as the performance measure. This problem is formulated as a mixed-integer programming problem. Based on a transformation between two different integer(More)
In beamformer design, the microphone array configuration is often prescribed and the filter coefficients are varied in order to improve on the noise reduction performance. However, the positions of the microphone elements play an important role in the overall performance and should be optimized at the same time. This problem is addressed in this paper. In(More)
In this paper, the design of near-field broadband beamformer is considered. The idea is to design the beamformer filter coefficients such that the error between the actual response and the desired response is minimized. This problem can be formulated as a minimax optimization problem and can be transformed into a linear semi-definite programming problem.(More)
In this paper, we consider a general class of optimal sensor scheduling problems in discrete time. There are N1 sensors available for acquiring data so as to estimate the needed but unknown signal. Only N2 out of the N1 sensors can be turned on at any moment, while different weights can be assigned to different sensors. This problem is formulated as a(More)
In this article, we consider the design of broadband beamformers with low complexity. In fact, the design problem is multi-objective in nature, trading off between speech distortion and noise suppression. Finding a balance between these two objectives is important in order to achieve a desired sound quality. These measures are introduced as the objectives(More)
In this paper, the design of distributed broadband beamforming system is studied. In the configuration, we assume that each microphone is equipped with wireless communications capability. Once their mutual distance information is collected, localization techniques can be used to estimate the microphone locations. A broadband beamformer can then be designed(More)
In this paper, we consider the design of finite-impulse response (FIR) filters, where the coefficients are expressed as sums of signed powers-of-two (SPT) terms. To consume less energy, the hardware implementation complexity is required to be reduced. That is, we need to minimize the number of SPT terms, subject to a given performance requirement. This can(More)