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7636436 Method for the performance testing of echo cancellers using an artificial segmented test signal  
A method for the performance testing of an echo canceller including the steps of transmitting a test signal to the echo canceller, recording an echo energy signal output from the echo canceller as...
7583613 Method of monitoring the quality of a realtime communication  
The invention concerns a method, a network element and a computer program product for monitoring the quality of a real-time communication ( 9 ) in a packet network ( 1 ) comprising at least two...
7573839 Line driver for an adaptive hybrid circuit  
A second output transmission signal (“TX 2 ”) added to a line driver is a scaled version of the main output transmission signal (“TX 1 ”). TX 2 is scaled from TX 1 by a variable scale...
7480377 Dual adaptive filter apparatus and method  
A method and apparatus for adapting dual filters is disclosed. In one aspect, a method may include transforming a signal, adapting a first adaptive filter based on the transformed signal,...
7477682 Echo cancellation for a packet voice system  
An apparatus and methods supporting improved echo cancellation in a packet network is disclosed. An embodiment of the present invention may permit a split-band communication system operating in a...
7406090 Managing a buffer for media processing  
A method and apparatus to perform buffer management for media processing are described.
7353002 Measuring a talking quality of a communication link in a network  
Device and method for measuring a talking quality of a communication link in a communications network ( 10 ). The device comprises measurement means ( 22; 31, 36 ) connected to the communication...
RE40054 Video-assisted audio signal processing system and method  
A circuit arrangement for controlling audio signal transmissions for a communications system that includes a microphone and a video camera. The arrangement comprises a video processor configured...
7312904 Apparatus, method and program for communication  
Facsimile communication is correctly performed even when an echo is generated in a communication line having a delay, by handling an echo signal in such a manner that when an echo of a CFR signal...
7221755 Method of capturing constant echo path information in a full duplex speakerphone  
A method of improving convergence of an echo canceller in a full duplex speakerphone, wherein the echo canceller includes LEC (Line Echo Canceller) and AEC (Acoustic Echo Canceller) portions,...
7194037 Active replica transformer hybrid  
A communication circuit includes a near end replication transmitter and a hybrid having an input in communication with an output of the near end transmitter. A high pass filter is responsive to the...
7177419 Methods and apparatuses for detecting and reducing non-linear echo in a multi-carrier communication system  
Apparatuses, systems, and methods for a multi-carrier communication system that detects and reduces an echo from a non-linear element present on the transmission medium. In an embodiment, a...
7173962 High-speed modem with uplink remote-echo canceller  
A high-speed modem operates at speeds as high as 64 kbps in both the downlink direction from a digital modem to an analog subscriber and at an increased speed in the uplink direction from the...
7133442 Rapid identification of transmission media channel characteristics  
Rapid identification and modeling of transmission media channel characteristics of a communications system using a correlation based technique. The technique provides a known training sequence used...
7068780 Hybrid echo canceller  
Systems and methods for reducing transmit echo in a transceiver are disclosed. A hybrid echo canceller includes a limited tap length FIR filter to cancel short-term echo, while an interpolated...
7062039 Methods and apparatus for improving adaptive filter performance by inclusion of inaudible information  
Adaptive filtering algorithm training signals incorporate adaptation-enhancing signals having properties, such as spectral whiteness and rapidly decaying auto-correlation between samples, which...
7043014 Apparatus and method for time-alignment of two signals  
A recently received portion of a transmit signal is utilized, and a pitch period of the received signal is determined. Then, the determined pitch period is utilized to search for similarities in...
7027593 Apparatus and method for echo control  
Determining the time delay between a transmitted signal and an echo. Then, the echo canceller is adjusted by the delay amount so that the echo canceller tail length is relatively short.
7023812 System and method for improving modem transmission through private branch exchanges, central offices, and other systems  
A modem including an echo canceller adapted to determine locations of far-end echo sources. The echo canceller is adapted to send a signal to turn off network echo suppressors and enter a training...
7020068 Echo and crosstalk cancellation  
A cancellation system comprises a channel circuit ( 11 ) for each noise source, such as echo in a particular cable pair. There are only eighty taps per channel, in two blocks (n_echo_a, f_echo_a)....
7003100 Modem with enhanced echo canceler  
A modem incorporating apparatus and methods to achieve computationally efficient echo cancellation. The apparatus include a cyclic echo synthesizer sub-canceler in the time domain and a echo...
6996231 Step size convergence control  
A method of converging a step size control for an adaptive filter of a communication channel including: (1) initializing a nominal step size value and a penalty point value; (2) combining the...
6959277 Voice feature extraction device  
In a conventional device for extracting voice features accurately without being influenced by noises, such as a voice recognition device, usually an input voice signal is processed first by a noise...
6947553 Communication system for controlling training of echo canceller and line switching system  
A communication system being made up of a two-wire/four-wire hybrid circuit, an echo canceller, and a control device and having functions of forming a plurality of communication paths and changing...
6934387 Method and apparatus for digital near-end echo/near-end crosstalk cancellation with adaptive correlation  
A communication transmitting and receiving system in which the effects of near-end echo and near-end crosstalk signal from the communication medium are mitigated by adaptively reproducing the...
6912281 Route delay sensitive echo cancellation  
Long distance telephone connections must commonly employ echo cancellers to eliminate irritating echo. The normal practice is to additionally employ non-linear processors (NLPs) as an integral...
6889066 Network echo suppression in mobile stations  
In one embodiment, a mobile station such as a dual-mode, AMPS and CDMA, handset communicates with an AMPS base station in a wireless communication system. The mobile station includes an acoustic...
6785384 Two-step algorithm for training an echo cancellation filter  
A two-step training method for the estimation filter in the echo cancellation (EC) path of the analog front-end (AFE) circuit for a modem, such as an asymmetric digital subscriber line (ADSL)...
6744884 Speaker-phone system change and double-talk detection  
A speaker-phone that is operable to perform system change detection, double-talk detection and if desired, optimal step-size control. The invention differentiates between system change and...
6738481 Noise reduction apparatus and method  
A method and noise reduction apparatus comprises a microphone array including a plurality of microphone elements for receiving a training signal including a plurality of training signal samples,...
6725066 Method of cancelling echoes in a telecommunications system and an echo canceller for the execution of the method  
A method of canceling echoes in a telecommunications system wherein an exchange of information takes place between a local subscriber and a subscriber at the remote end of a transmission link and...
6707912 Method and apparatus for setting a step size for an adaptive filter coefficient of an echo canceller  
The step sizes for tap positions of an adaptive filter ( 124 ) in an echo canceller ( 125 ) for canceling an echo signal are individually selected based upon a profile of the echo environment. A...
6650627 Tone detection in communication networks  
A communication circuitry for providing effective detection of tones in a communication network. The communication circuitry comprises filtration circuitry, summation circuitry, detection...
6636604 Method and device for suppressing echo in a hands free device such as a telephone  
An method and a device for echo suppression in a handsfree apparatus, particularly for a telephone is disclosed. With the aid of a control unit, control signals are generated from the signal of the...
6590976 Two-step algorithm for training an echo cancellation filter  
A two-step training method for the estimation filter in the echo cancellation (EC) path of the analog front-end (AFE) circuit for a modem, such as an asymmetric digital subscriber line (ADSL)...
6553122 Method and apparatus for multi-channel acoustic echo cancellation and recording medium with the method recorded thereon  
Even if received signals are highly cross-correlated, echoes can be effectively cancelled and no psychoacoustical problems arise. A received signal x i (k) (where i=1, 2, . . . , N) and an...
6510225 Ultrasonically-calibrated fast-start echo canceller for cellular and pcs telephone car kits  
The present disclosure describes an ultrasonically-calibrated fast-start adaptive echo canceller system. The system consists of at least one ultrasonic transducer for transmitting ultrasound signal...
6510224 Enhancement of near-end voice signals in an echo suppression system  
An enhanced near-end voice signal may be generated in a hands-free environment by receiving an audio signal, generating an estimated acoustic echo signal, and generating a processed signal by...
6507653 Desired voice detection in echo suppression  
A hybrid echo suppresser and associated methods of use provide echo suppression in a bi-directional communications system, while minimizing desired-voice signal disruption. The hybrid echo...
6498850 Multichannel echo canceller with a compander  
A compander circuit ( 20 ) for echo cancellation in telecommunications apparatus with an estimator module ( 21 ) for estimating an echo coupling and a delay of a line echo and a characteristic...
6496581 Coupled acoustic echo cancellation system  
Full acoustic coupling and echo cancellation is provided in implementations where there is acoustic coupling between acoustic zones. In acoustic echo cancellation systems, including active acoustic...
6456697 Device and method of channel effect compensation for telephone speech recognition  
Device and method of channel effect compensation for a telephone speech recognition system is disclosed. The telephone speech recognition system comprises a compensatory neutral network and a...
6442275 Echo canceler including subband echo suppressor  
Residual echo components resulting from an adaptive echo canceler are minimized by employing a subband echo suppressor. The residual echo components are minimized by individually, controllably...
6347140 Echo canceling method and apparatus  
In a communication system ( 100 ), a first echo return loss through communication system ( 100 ) associated with a first call connection between a caller ( 111 ) and a first caller ( 114 ) is...
6243462 Echo canceller and method of controlling the same  
On the basis of tap coefficients which a tap coefficient updating circuit updates in succession, a maximum-tap position detecting unit, a fluctuation width detecting unit and a comparator detect a...
H001885 Apparatus and method for controlling the operational state of an echo canceller  
An apparatus for processing wireless telecommunications is provided. The apparatus includes an echo canceller module. An echo canceller module controller is connected to the echo canceller module....
6108720 Echo canceling modem which dynamically switches sizes of sample buffer between first size for quick response time and second size for robustness to interrupt latency  
An apparatus for and method of implementing a novel buffer based full duplex communication system is disclosed. The disclosed invention is particularly useful in native signal processing systems...
5909426 Orthogonal LMS algorithms for fast line echo canceler training  
An echo canceler for calculating an echo impulse response during a training sequence, wherein a sequence of data samples is selected such that a full rank data correlation matrix comprised of such...
5892757 Asymmetric duplex modem utilizing narrow band echo cancellation  
A full-duplex modem having improved transmission speeds over voice grade telephone circuits that extends the concepts of asymmetric transmission to include echo cancellation techniques. The...
5841809 Access line termination unit  
A post-cursor tap coefficient of a decision feedback equalizer is used as a coefficient of an echo canceler during a cold-start echo canceler training period in which a communication start-up...
Matches 1 - 50 out of 72 1 2 >