Fouret, JoachimAhmadi, MasoudEl-Hennawey, MohamedLiao, Can2020-02-052020-02-052008US8014468B2 2004-12-15 2011-09-06 Microsoft Corporation Energy detection receiver for UWB CN100562925C * 2005-09-29 2009-11-25 华为技术有限公司 Method for automatic recognizing voice for limited range US8804700B2 2008-07-16 2014-08-12 Freescale Semiconductor, Inc. Method and apparatus for detecting one or more predetermined tones transmitted over a communication network US8233951B2 2010-01-25 2012-07-31 Research In Motion Limited Error correction for DTMF corruption on uplinkhttps://t.ly/W32REMSA Google ScholarA fast DTMF detector for filtering a packetized linear voice signal to identify whether the voice signal contains a DTMF tone. The detector includes a plurality of parallel notch filters for knocking down DTMF tones. The energies of the filtered signals output by the notch filters are calculated and criteria based upon the calculated energies are applied to determine if the voice signal contains a DTMF tone. The criteria include an energy differential test, a twist test, a low frequency tolerance test, a high frequency tolerance test, a packetized linear voice signal energy level test, a dial tone filtered signal energy level test, and a 1004 Hz filtered signal energy level test.enUniversity of DTMF detectionOther