Echo Cancellation, Art or Science? Part III

  • Posted by admin
  • On August 29, 2012
Background In previous posts on echo cancellation we discussed the challenge of echo cancellation algorithms to efficiently handle the echo path, especially when it is long and volatile, and the complexity introduced by the invalidation phenomena.  In this post we will discuss another aspect in echo cancellation called Howling.
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Echo Cancellation, Art or Science? Part II

  • Posted by admin
  • On July 20, 2012
Background In the previous post on acoustic echo cancellation we discussed the importance and the challenge in handling of the echo path. In this post we will discuss a different aspect that echo cancellation algorithm must handle. It is not rare that users change the setting of their audio device during a call. For example […]
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Echo Cancellation, Art or Science? Part I

  • Posted by admin
  • On July 1, 2012
Background First, let us apologize that this post is going to be a bit technical. Don’t worry we will try to keep it as simple as possible.  Echo cancellation, and more specifically Acoustic Echo Cancellation (AEC) is theoretically a very simple algorithm. The AEC algorithm receives a reference signal (i.e. the audio played to the […]
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Improving Audio Quality for Skype

  • Posted by admin
  • On June 1, 2012
Background For many years, Skype has been one of the most popular softphones. Since Skype is being used on many brands of hardware and multiple network connections, there are bound to be occasions in which the audio quality is not satisfactory enough. We, at SoliCall, are constantly being approached for advice on ways to improve […]
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Echo Cancellation with Flash Clients

  • Posted by admin
  • On December 6, 2011
Background In the beginning of this year, Adobe has released an acoustic echo cancellation as an integral part of its platform. Based on the feedback we are getting, the problem of echo was successfully reduced but not in all environments and especially not in environments that include mobile platforms.  SoliCall’s network echo cancellation technology could […]
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Improving Audio Quality with Analog Telephone Adapter (ATA)

  • Posted by admin
  • On November 14, 2011
Background One of the first steps SMBs take towards VoIP is to add ATA to their existing analog telephone network. There are many well known brands of ATAs in the market today like Linksys PAP2, Cisco PAP2T, Grandstream HandyTone and others. Regularly we are requested to improve audio quality in such telephony systems – especially […]
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Noise Reduction and Echo Cancellation for existing VoIP Networks

  • Posted by admin
  • On October 8, 2011
Background Many times we are asked for ways to cancel noise and improve audio quality in existing telephony networks.  The majority of the requests come from call centers and SMBs that are looking for simple plug-and-play solutions to resolve audio quality issues that they are facing.  Since most of these request arise for companies that […]
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Acoustic Echo Cancellation and Sound Cards

  • Posted by admin
  • On September 1, 2011
Clock Synchronization Acoustic Echo Cancellation (AEC) is a method of removing the echo from the audio signal captured by the microphone. This is done by using the audio that is played to the speakers as a reference audio signal. Most AEC algorithms require that both audio signals, i.e. the signal captured from the microphone and […]
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Tips for Developing VoIP on Mobile Devices (Android,iOS,…)

  • Posted by admin
  • On August 1, 2011
CPU Consumption One of the main problems in mobile devices is their limited CPU Power. As a result the delay in the audio signal is increased and from time to time portions of the audio signal might get lost. In order to resolve these problems, you need to verify that your VoIP application is optimized […]
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Audio Quality When Using Speakerphone During Phone Calls

  • Posted by admin
  • On July 5, 2011
  Background There are different scenarios in which calls are made using speakerphones. For example: In manufacturing floor where the employees want to have an open communication channel without the limitation of headset or handset. When using intercom devices. When more than one person needs to listen to the call (e.g. in conference rooms). When […]
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