Range extension and short range performance enhancement in TDMA digital cellular

Author

Wei, Bo ; Gibson, Jerry D.

Author_Institution

Dept. of Electr. Eng., Southern Methodist Univ., Dallas, TX, USA

Volume

1

fYear

2002

fDate

3-6 Nov. 2002

Firstpage

553

Abstract

A new system enhancement method is proposed for the EIA/TIA-136 system offering both channel operational range extension and improved performance within the current operational range. The research presented investigates the application of the narrowband adaptive multi-rate (NB-AMR) speech codec and the wideband AMR (WB-AMR) codec, both originally designed for the 200 kHz GSM channel, in the TDMA (TIA/EIA-136) 30 kHz system. In particular, we investigate adaptively allocating bits between NB/WB speech coding and error control within the limited channel bandwidth. Four modes out of seventeen have been carefully chosen for the new TDMA/AMR system. Switching between codec rates as channel conditions change produces range extension below a C/I of 15 dB while also improving performance in the existing operational range above 15 dB. Time slot formats are unchanged so that the method is completely compatible with existing 136 systems.

Keywords

cellular radio; channel coding; combined source-channel coding; digital radio; error correction codes; speech codecs; time division multiple access; 200 kHz; 30 kHz; EIA/TIA-136 system; GSM channel; NB-AMR speech codec; NB/WB error control coding; NB/WB speech coding; RSC codes; TDMA-136 system; TIA/EIA-136 system; UEP; WB-AMR; bit allocation; channel bandwidth; codec rates; digital cellular systems; narrowband adaptive multirate; narrowband/wideband; range extension; recursive systematic convolutional; short range performance enhancement; soft-decision decoding; time division multiple access; time slot formats; unequal error protection; wideband adaptive multi-rate; Bit rate; Channel coding; Degradation; Fading; Protection; Speech codecs; Speech coding; Telecommunication standards; Time division multiple access; Wideband;

fLanguage

English

Publisher

ieee

Conference_Titel

Signals, Systems and Computers, 2002. Conference Record of the Thirty-Sixth Asilomar Conference on

Conference_Location

Pacific Grove, CA, USA

ISSN

1058-6393

Print_ISBN

0-7803-7576-9

Type

conf

DOI

10.1109/ACSSC.2002.1197242

Filename

1197242