Matches 1 - 50 out of 132 1 2 3 >
Match Document Document Title
7298838 Adaptive cancellation network system and method for digital subscriber line  
A method for reducing transmit echo in a DSL modem comprises selecting at least one cancellation device of a plurality of cancellation devices. An attenuation signal is generated using the selected...
7231036 Anti-howling circuit detecting howling from effect of predicted echo signal  
In a system in which echo transferred from a received signal to an outgoing signal is canceled by subtracting an adaptively predicted echo signal from the outgoing signal, howling is detected by...
7146315 Multichannel voice detection in adverse environments  
A multichannel source activity detection system, e.g., a voice activity detection (VAD) system, and method that exploits spatial localization of a target audio source is provided. The method...
7146003 Noise level calculator for echo canceller  
A noise level calculator for detecting noise in a telephone line echo canceller that utilizes adaptive filters enables silencing of noise switching so that it is not heard on the far end side. The...
7123714 Speakerphone having improved outbound audio quality  
A telephone ( 310 ) and a method for providing outbound audio when the telephone is operating in a speakerphone mode. A first data unit ( 350 ) including a first unit type identifier ( 360 ) can be...
7120246 Computer apparatus having a multiway acoustic output and input system  
A computer apparatus is provided, which has a multipath acoustic output system and a multipath acoustic input system, which includes parts for enabling an adaptation of the filter of an acoustic...
7106856 Method and apparatus for performing echo cancellation within a communication network  
A switching center for use in a communication network includes a pool of echo cancellation units for use in providing echo cancellation services to users associated with the switching center on an...
7068779 Control of echo cancellers in a telecommunication system  
The invention relates to a communications network, including switching centers having no echo canceling equipment and switching centers having echo canceling equipment. The switching centers are...
7062041 Device and method for carrying out multichannel acoustic echo cancellation with a variable number of channels  
A multichannel full-duplex audio signal transmission system, comprising an adaptive filter ( 2 ) provided for multichannel acoustic echo cancellation. A channel combining device ( 5 ) is provided...
7046794 Double talk activity detector and method for an echo canceler circuit  
A double talk activity detector ( 30 ) and method for an echo canceler circuit ( 10 ) improves the probability of detecting a double talk condition based on at least pre-echo canceler uplink data (...
7043013 Method for adaptive control of multichannel acoustic echo cancellation system and device therefor  
A method for adaptive control of a multi-channel echo cancellation system including N loudspeakers, where N is an integer greater than or equal to 2, and M microphones, where M is an integer...
7039181 Consolidated voice activity detection and noise estimation  
Methods and apparatus compensating for background noise associated with a transmitted signal. In a first embodiment, an adder combines an echo estimate with the the transmitted signal to form a...
7020278 Echo canceller having improved non-linear processor  
A non-linear processor for use in an echo canceller is set forth. The non-linear processor includes a center clipping digital filter receiving an echo compensated signal. The non-linear processor...
7003101 Subband echo location and double-talk detection in communication systems  
A method of controlling an echo canceller in a communications channel, is disclosed wherein input signals from the communications channel are first subbanded into a subband. Echo locations are then...
6990194 Dynamic balance control for telephone  
A telephone includes a transmit channel and a receive channel, each including a bank of sub-band filters having a VAD coupled one to each sub-band filter. Each VAD measures the spectral energy in a...
6963642 Band-by-band full duplex communication  
A telephone includes a first channel having a microphone input and a line output, a second channel having a line input and a speaker output, and each channel having a plurality of band pass filters...
6961423 Method and apparatus for performing adaptive filtering  
A communication system having an echo canceller is disclosed. One embodiment of the echo canceller includes an adaptive filter used to provide an estimate of reflected echo which is removed from...
6952473 System and method for echo assessment in a communication network  
A method includes receiving a plurality of packets from at least two voice packet streams. The method also includes generating at least two voice signals using the plurality of packets. Each voice...
6952472 Dynamically estimating echo return loss in a communication link  
A method of estimating an echo return loss of a communication link measures the peak power value of a signal received from a far end of a communication link and the corresponding peak power value...
6947773 Method and apparatus for reducing echo feedback in a communication system  
A method and apparatus for reducing echo feedback in a wireless communication system ( 10 ) is accomplished when a receiving communication unit ( 24 ) senses a feedback signal, or echo, via an...
6947552 Echo canceler with echo path change detector  
An echo canceler includes an adaptive filter that adapts to changes in an echo path, a double-talk detector, and an echo path change detector. The echo path change detector estimates the loss on...
6947549 Echo canceller  
An echo canceller includes two parallel filters and a controller. The controller chooses the best of the two filters for the final echo cancellation. The filter coefficients are exchanged between...
6944289 Delay insertion for echo cancellation, with echo supression, in a communication network  
The invention provides an apparatus and method for bulk delay insertion prior to echo cancellation, with echo suppression. The exemplary apparatus embodiment ( 100 ) bandpass filters ( 120 ) and...
6944288 Double-talk and path change detection using a matrix of correlation coefficients  
A process is described which generates matrix coefficients using zero-lag auto and cross-correlations from signals commonly found in echo cancellers. Double-talk and path changes are then detected...
6940972 Controlling echo cancellation  
Controlling echo cancellation includes receiving signals associated with a call. A signal of the signals is detected. Whether the detected signal is a high speed signal or a low speed signal is...
6940971 Method and system for activating echo suppression in a communications network  
A method for allocating echo canceling devices in a telecommunications network having at least two networks connected to one another by network switching nodes. The network switching nodes have...
6931101 Method and apparatus for inband testing of an echo canceller  
Provided is a method and apparatus for inband testing of an echo canceller. The apparatus includes a signal generator for generating an excitation signal including a preamble portion and a test...
6925174 Interaction between echo canceller and packet voice processing  
System and method for processing communication signals in a communication system having a detector for detecting a parameter of a communication signal. A communication signal is provided to a...
6920219 Method and apparatus for providing echo cancellation  
A method for providing echo cancellation between a first and second communication unit detects an echo condition ( 200 ) between first and second communication units. In addition, the method...
6912209 Voice gateway with echo cancellation  
A network gateway is configured to facilitate on line and off line bi-directional communication between a number of near end data and telephony devices with far end data termination devices via a...
6904146 Full duplex echo cancelling circuit  
Sub-band filtering, adaptive echo cancellation, and residual echo suppression are selectively and separately applied in hierarchical order under the control of a circuit that monitors four separate...
6868158 Echo processing apparatus  
An echo canceller has a high-pass filter 11, a speaker 3, an A/D converter 6, and an echo canceller 7 . The high-pass filter 11 suppresses a low-frequency component in a received signal....
6850783 Methods and apparatus for mitigating the effects of microphone overload in echo cancelation systems  
Methods and apparatus for echo and noise cancelation contemplate occasional saturation of an echo and/or noise containing source signal and control adaptation of a cancelation filter to minimize...
6839427 Method and apparatus for echo canceller automatic gain control  
A method and apparatus that performs specific automatic gain control in an echo canceller ( 16 ). The disclosed method and apparatus utilize a low complexity algorithm that performs automatic gain...
6839426 Echo cancellor  
An echo cancellor having a main tap coefficient holding section to renew a tap coefficient used to establish a pseudo transmission characteristic of an echo path and a sub tap coefficient holding...
6836547 Protecting an echo canceller against random transitions in echo paths  
A method and apparatus is capable of detecting the presence of a non-linear echo path as well as transitions from non-linear echo path to linear echo path and vice versa. Additionally, when...
6757384 Robust double-talk detection and recovery in a system for echo cancelation  
Echoes caused by discontinuities in a telecommunications transmission lines cause double talk which cause divergence problems with echo cancellers. Divergence problems in echo cancellers cause...
6751314 Dynamic allocation of resources for echo cancellation  
A method is presented for dynamic resource allocation in a speech signal echo canceler enabling more efficient echo cancellation and as a result the ability for an Integrated Circuit to handle...
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...
6738482 Noise suppression system with dual microphone echo cancellation  
An active noise suppression system for use in noisy environments includes a dual microphone noise suppression system in which the echo between the two microphones is substantially canceled or...
6735303 Periodic signal detector  
A periodic signal detector includes sample counting means for counting a number of samples between adjacent zero cross points in an input signal, the sample counting means outputting the number of...
6700979 Echo canceller  
An echo canceler provided with a noise detecting section which holds signals showing a presupposed ambient noise such as a horn of a vehicle. The noise detecting section is adapted to monitor a...
6694019 Method and apparatus for infinite return loss handler for network echo canceller  
A communication device and method for detecting an infinite return loss (IRL) condition and temporarily halting or bypassing operations of an echo canceller in response to detecting that condition....
6665402 Method and apparatus for performing echo cancellation  
An echo cancellation device for reducing a magnitude of an echo occurring in a voice signal propagating in a channel of a communication system. The echo cancellation device is capable to...
6662027 Method of arbitrating speakerphone operation in a portable communication device for eliminating false arbitration due to echo  
A speakerphone arbitration method is used to eliminate the effects of echo in imperfect telephone circuits. The method assumes that speech energy received at the speaker phone is an echo, unless...
6658107 Methods and apparatus for providing echo suppression using frequency domain nonlinear processing  
Frequency domain nonlinear processing techniques are applied in the context of echo suppression. According to exemplary embodiments, the filtering characteristic of a nonlinear processor is...
6622030 Echo suppression using adaptive gain based on residual echo energy  
An echo suppressor for bi-directional communications includes an echo canceler and a residual echo suppressor having variable gain. The gain of the residual echo suppressor is controlled based on a...
6611593 Call control of ancillary telecommunications equipment using continuity tests  
System and method for controlling an ancillary telecommunications device such as an echo canceller within a telecommunications system. The system and method include and involve a switching system...
6591118 Method for switching a mobile telephone for a transmitted/received voice signal in a speakerphone mode  
Switching a mobile telephone for selectively receiving or transmitting a voice signal in a speakerphone mode by counting the number of the full-rate voice data received from the sender, and...
6580793 Method and apparatus for echo cancellation with self-deactivation  
An echo canceling system with self deactivation includes an echo canceller based on an adaptive filter, and an echo detector. The adaptive filter determines an estimate of an echo signal present in...
Matches 1 - 50 out of 132 1 2 3 >