An integrated acoustic echo and noise cancellation system for hands-free telephony is presented. The proposed system includes a new residual echo cancellation scheme based on spectral analysis and a new double-talk detector suitable for real-time implementation. Residual echo is whitened via AR analysis during no near-end-talk period and is cancelled by noise reduction. Removing speech characte...

Echo is defined as the delayed and attenuated version of the original signal produced by some device, such as a loudspeaker. As a consequence a person listens to a delayed replica of its own voice signal. This is an undesired effect that appears whenever the output signal is fed back into the system’s input and it can be quite disturbing on voice conversations. Echo arises in long distance comm...

Echo cancellation is one unavoidable module in any voice related communication systems such as telephone, mobile and VOIP. In several applications run time high speed echo cancellation can give better quality of service. Real time echo cancellation is an important feature for hands-free operation of telecommunication equipment like mobile phones. A desirable acoustic echo control should be capa...

While many previous studies have examined acoustic echo cancellation (AEC) in terms of quality, computation complexity, and implementation issues on DSP processors, this work evaluates quality-delay-computation trade-off of unconstrained frequency-domain recursiveleast-square AEC algorithm on general purpose microprocessors. Specially, trade-off among echo cancellation quality, sampling delay, ...

We show: Theorem 0.1. Let K be a fully LS(K)-tame and short abstract elementary class (AEC) with amalgamation. Write H1 := i(2LS(K))+ and assume that K is categorical in some λ ≥ H1. The following are equivalent: (1) K≥H1 has primes over sets of the form M ∪ {a}. (2) K is categorical in all λ′ ≥ H1. Note that (1) implies (2) appears in an earlier paper. Here we prove (2) implies (1), generalizi...

Article history: Available online 7 May 2009

A novel acoustic echo canceller for speakerphone system based upon Iterative Maximal Length Correlation (IMLC) algorithm is proposed. This algorithm is robust to double talk because of the nature of the ML sequence; it also iteratively reduces the far-end speech's effects. This simple structure was found to perform very well. We also perform a rigorous convergence analysis and derive the lower ...

| 1. Graduate School of Design, Harvard University, Gund Hall, 48 Quincy Street, Cambridge, MA, 02138, USA. [email protected] 2. Includes the value of construction work done during the year for construction work performed by general contractors and special trade contractors 3. Includes all establishments that were in business at any time during the year. Construction establishments that ...

We use orthogonality calculus to prove a downward transfer from categoricity in a successor in abstract elementary classes (AECs) that have a good frame (a forking-like notion for types of singletons) on an interval of cardinals: Theorem 0.1. Let K be an AEC and let LS(K) ≤ λ < θ be cardinals. If K has a type-full good [λ, θ]-frame and K is categorical in both λ and θ, then K is categorical in ...

We show that Shelah’s Eventual Categoricity Conjecture follows from the existence of class many strongly compact cardinals. This is the first time the consistency of this conjecture has been proven. We do so by showing that every AEC with LS(K) below a strongly compact cardinal κ is < κ tame and applying the categoricity transfer of Grossberg and VanDieren [GV06a]. These techniques also apply t...