Sound acoustics

Ingenieurbüro für Nachrichtentechnik und Akustik

Quality enhancement of Standardized CODECs

Up to now the quality of the standardized TETRA Codec is  limited.

Especially frequently appearing background noise introduces remarkable quality degradation, leading to unacceptable intelligibility.

The objective quality measure amounts less than 3 on the MOS scale for about 50 % of all applications in natural environment .

The new parameterization is also suitable for quality enhancement of current products.


Optional extensions as the quality optimization of stolen frames and a method for bandwidth extension of the speech signal at a standard corresponding bit rate are available for TETRA-C.


Please contact us if you need more information about this topic.


TETRA-C is a new standard conform SW library in C++.


A remarkable quality enhancement could be achieved with the aid of hearing adequate parameterisation of 25 parameters.


In spite of this changing the parameter transfer is standard compatible.


TETRA-C requires only 1% of the computational power of a simple PC.

Objective quality evaluation at different test scenarios.