Polycom OMNISMART OMNIVS500U Instrukcja Użytkownika

How to Choose an Acoustic Echo Canceller Application Note Polycom Installed Voice Business Group September 2004

The two most critical states of the echo canceller are receive and double-talk. The receive state is the only opportunity for the echo canceller to c

acoustics have such a large impact. If this cannot be arranged, at least consider the operating environment differences in each case in the final dec

A Short Glossary of AEC Related Terms Near end The end of the connection where the echo canceller is located. This is where the echoes take place.

Technical Support For support on the Vortex product line, call toll-free (USA/Canada) 888-248-4143, then select option 1, then option 3. For exclus

Introduction Acoustic echo cancellers (AEC) greatly enhance the audio quality of a multipoint hands-free communications system. They allow conferenc

AECNonlinearProcessingMicSpeakerEchoesNear speechFar speechFar speechNear speech +echoes + distortionFar EndNear EndXMTRCVDistortion Figure 1: Illust

frequently, if at all. With acoustic echo cancellation, the echo path is very complex (dozens or hundreds of reflections), lasts 100-200 ms, and can

Form Factor The form factor of the solution is very important because it determines how useful it is in an application. The performance of the produ

Step 2: Eliminate the products that don’t meet G.167 or the tail length needs of the application. It is relatively easy to determine how well an AEC

Room Acoustics G.167 testing is performed in real rooms. If the product meets the requirements in these rooms, it is compliant. A device that is G.

The equation assumes that both the microphone and the speaker are mounted on the same wall (which is the worst case in terms of the number of reflect

Step 3: Judge audio quality and state machine performance by comparative listening. Ideally, the AEC will let speech signals pass through it unharmed