Observations of real telephone conversations show that for much of the time one or other user is listening, not talking. During that time there is no need to transmit audio from the listener's microphone to the talker's earpiece, and when call gapping is used, the audio is not transmitted. This frees the bandwidth for other users.
US Patent Issued to Heidenhain on May 10 for "Encoder Device and Gapping and Centering Device for an Encoder Device" (California Inventor)
May 14, 2011; ALEXANDRIA, Va., May 14 -- United States Patent no. 7,939,795, issued on May 10, was assigned to Heidenhain Corp. (Schaumburg,...