The loss of the beginning or end of a speech burst is known as clipping, this is usually a result of voice switching controlled by voice activity detection. The main source of clipping within a TETRA system are handsfree terminals. The TETRA CODEC is capable of operating in a discontinuous mode like GSM but there appear to be no terminals available which can operate in this mode.
Information on recommended charactistics of handsfree telephone operation can be found in [P.340] which replaces [P.34].
There is no requirement for clipping parameters or operation other than as specified as part of the TETRA CODEC, therefore no requirement shall be specified.
There is a related problem in non-duplex calls with the operation of PTT. If the user doesn't wait for the PTT to be acknowledged then several words can be lost at the start of their transmission.
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