Title :
A spectral efficiency comparison of UMTS-FDD and 1xRTT cdma2000 for voice services
Author_Institution :
Nortel Networks, Richardson, TX, USA
Abstract :
Third-generation (3G) cellular technologies are designed to carry more traffic than their second-generation (2G) predecessors. Spectral efficiency for voice services is compared between two competing technologies by simulation of their physical layer wireless transmission under IMT-2000 channel conditions. Assuming 25% of mobiles at 3 km/hr, 37.5% at 30 km/hr, and 37.5% at 100 km/hr, UMTS 12.2 kb/s AMR speech with spreading factor 128 is 0.78 dB more spectrally efficient than 8.6 kb/s 1xRTT RC4 (radio configuration 4) speech. UMTS 10.2 kb/s with spreading factor 128 is 0.6 dB more efficient, while UMTS 7.95 kb/s AMR speech with spreading factor 256 is 0.72 dB less efficient, than RC4. 1xRTT 8.6 kb/s RC3 speech is 0.98 dB more efficient than RC4. These calculations assume sufficient OVSF (orthogonal variable spreading factor)/Walsh codes exist in the system. Thus, efficiency is based on power utilization rather than code depletion.
Keywords :
3G mobile communication; cellular radio; combined source-channel coding; frequency division multiplexing; telecommunication channels; telecommunication traffic; voice communication; 1xRTT cdma2000; 3 to 100 km/h; 3G cellular technologies; 7.95 to 12.2 kbit/s; IMT-2000 channel conditions; IS-95; UMTS-FDD; Walsh codes; combined source channel coding; physical layer wireless transmission; power utilization; radio configuration; spectral efficiency comparison; spreading factor; voice services; 3G mobile communication; Cellular networks; Downlink; Interleaved codes; Lakes; Power control; Power system modeling; Speech; Telecommunication traffic; Traffic control;
Conference_Titel :
Vehicular Technology Conference, 2002. Proceedings. VTC 2002-Fall. 2002 IEEE 56th
Print_ISBN :
0-7803-7467-3
DOI :
10.1109/VETECF.2002.1040405
