Title :
Real-time implementation of a high quality CELP codec for digital mobile radio system
Author :
Andreotti, F.G. ; Maiorano, V. ; Vetrano, L. ; Zanoni, F.
Author_Institution :
Italtel SIT, Settimo, Italy
Abstract :
The authors describe a real-time implementation of a voiceband codec suitable for the GSM Half-Size Digital Mobile Radio (DMR) system at 900 MHz. This codec exploits the CELP (code excited linear prediction) algorithm running at 6.3 kbit/s in connection with a channel coding scheme, adding 5.1 kbit/s of redundancy to reach the final rate of 11.4 kbit/s for the traffic channel. A comparative evaluation between the full-rate and the half-rate source codecs is presented: the speech quality is almost the same on a wide range of experiments and different speakers
Keywords :
codecs; digital radio systems; mobile radio systems; speech intelligibility; 5.1 to 11.4 kbit/s; 900 MHz; CELP codec; DMR; Digital Mobile Radio; Groupe Speciale Mobile; channel coding scheme; code excited linear prediction; different speakers; digital mobile radio system; full-rate source codecs; half-rate source codecs; real-time implementation; redundancy; speech quality; traffic channel; voiceband codec; Algorithm design and analysis; Bit rate; Channel coding; Filters; Land mobile radio; Real time systems; Speech analysis; Speech codecs; Speech synthesis; Standardization;
Conference_Titel :
Circuits and Systems, 1991., IEEE International Sympoisum on
Print_ISBN :
0-7803-0050-5
DOI :
10.1109/ISCAS.1991.176339
