Journal ArticleDOI
Modulated filter banks with arbitrary system delay: efficient implementations and the time-varying case
Gerald Schuller,Tanja Karp +1 more
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TLDR
A new method for the design and implementation of modulated filter banks with perfect reconstruction is presented, based on the decomposition of the analysis and synthesis polyphase matrices into a product of two different types of simple matrices, replacing the polyphase filtering part in a modulatedfilter bank.Abstract:
We present a new method for the design and implementation of modulated filter banks with perfect reconstruction. It is based on the decomposition of the analysis and synthesis polyphase matrices into a product of two different types of simple matrices, replacing the polyphase filtering part in a modulated filter bank. Special consideration is given to cosine-modulated as well as time-varying filter banks. The new structure provides several advantages. First of all, it allows an easy control of the input-output system delay, which can be chosen in single steps of input sampling rate, independent of the filter length. This property can be used in audio coding applications to reduce pre-echoes. Second, it results in a structure that is nearly twice as efficient as performing the polyphase filtering directly. Perfect reconstruction is a structurally inherent feature of the new formulation, even for nonlinear operations or time-varying coefficients. Hence, the structure is especially suited for the design of time-varying filter banks where both the number of bands as well as the prototype filters can be changed while maintaining perfect reconstruction and critical sampling. Further, a proof of effective completeness is given, and the design of equal magnitude-response analysis and synthesis filter banks is described. Filter design can be performed by nonconstrained optimization of the matrix coefficients according to a given cost function. Design and audio-coding application examples are given to show the performance of the new filter bank.read more
Citations
More filters
Book ChapterDOI
Multirate Systems and Filter Banks
Tapio Saramaki,Robert Bregovic +1 more
TL;DR: In this article, the basic operations of these filter banks are considered and the requirements are stated for alias-free, perfect-reconstruction (PR), and nearly perfect reconstruction (NPR) filter banks.
Journal ArticleDOI
Perceptual coding of digital audio
T. Painter,Andreas Spanias +1 more
TL;DR: This paper reviews methodologies that achieve perceptually transparent coding of FM- and CD-quality audio signals, including algorithms that manipulate transform components, subband signal decompositions, sinusoidal signal components, and linear prediction parameters, as well as hybrid algorithms that make use of more than one signal model.
Journal ArticleDOI
Perceptual audio coding using adaptive pre- and post-filters and lossless compression
TL;DR: A subjective listening test of the combined pre-filter/lossless coder and a state-of-the-art perceptual audio coder (PAC) shows that the new method achieves a comparable compression ratio and audio quality with a lower delay.
Book
Audio Signal Processing and Coding
TL;DR: This chapter discusses signal processing Essentials, audio Coding Standards and Algorithms, and quality measures for Perceptual Audio Coding.
Patent
Radio communication system employing spectral reuse transceivers
R. Brent Saunders,Thomas F. Smaidris,Edward C. Gerhardt,William R. Highsmith,Pouehll Gregori M,Odom Dehvid M,Larry W. Koos +6 more
Abstract: A spectral reuse transceiver-based communication system conducts communications between a master site and a plurality of remote sites using a selected portion of a communication bandwidth containing a plurality of sub-bandwidth channels. Each remote site transceiver monitors the communication bandwidth for activity on the sub-bandwidth channels, and informs a master site transceiver which sub-bandwidth communication channels are absent communication activity and therefore constitute clear channels. The master site transceiver compiles an aggregate list of clear channels from all the remote sites and then broadcasts the aggregate list to the remote sites. The master site and a remote site then conduct communications therebetween by frequency-hopping and/or orthogonal frequency multiplexing among the clear channels using an a priori known PN sequence.
References
More filters
Book
Multirate Systems and Filter Banks
TL;DR: In this paper, a review of Discrete-Time Multi-Input Multi-Output (DIMO) and Linear Phase Perfect Reconstruction (QLP) QMF banks is presented.
Book
Wavelets and Subband Coding
Martin Vetterli,Jelena Kovacevic +1 more
TL;DR: Wavelets and Subband Coding offered a unified view of the exciting field of wavelets and their discrete-time cousins, filter banks, or subband coding and developed the theory in both continuous and discrete time.
Book ChapterDOI
Factoring wavelet transforms into lifting steps
Ingrid Daubechies,Wim Sweldens +1 more
TL;DR: In this paper, a self-contained derivation from basic principles such as the Euclidean algorithm, with a focus on applying it to wavelet filtering, is presented, which asymptotically reduces the computational complexity of the transform by a factor two.
Book ChapterDOI
Multirate Systems and Filter Banks
Tapio Saramaki,Robert Bregovic +1 more
TL;DR: In this article, the basic operations of these filter banks are considered and the requirements are stated for alias-free, perfect-reconstruction (PR), and nearly perfect reconstruction (NPR) filter banks.
Book
Signal processing with lapped transforms
TL;DR: Applications of transforms in signal processing signal processing in subbands lapped orthogonal transforms the modulated lapped transform heirarchical lapped transforms applications of lapping transforms.