Uncoded Error Performance of eCall Modem through AMR Codec and AWGN

Author

Brandenburg, Jacob C. ; Liu, J.Q.

Author_Institution

Dept. of Electr. & Comput. Eng., Wayne State Univ., Detroit, MI, USA

fYear

2013

fDate

2-5 Sept. 2013

Firstpage

1

Lastpage

4

Abstract

Data communications through the voice channel of the cellular network are important for telematics applications such as automatic vehicle crash notification, an implementation of which is the pan- European eCall system scheduled for deployment in 2015. The cellular voice channel includes the vocoder which is designed for compressing speech waveforms and is a hindrance for data communications. No mathematical model exists for the vocoder as a data communications channel. Thus, in this paper, the uncoded bit error rate (BER) is found by simulation using the bit-exact C- code implementation of the vocoder. The adaptive multi-rate (AMR) vocoder is used in GSM, the network on which eCall runs and is the one used in these simulations. The uncoded BER is presented for different compression rates along with other effects of the vocoder such as a wake-up effect and the signal-to-distortion ratio.

Keywords

AWGN; cellular radio; data compression; decoding; error statistics; speech codecs; speech coding; vocoders; AMR codec; AMR vocoder; AWGN; adaptive multirate vocoder; automatic vehicle crash notification; bit-exact C-code implementation; cellular network; data communication channel; eCall modem; pan-European eCall system; signal-to-distortion ratio; speech waveform compression; telematics application; uncoded BER; uncoded bit error rate; uncoded error performance; voice channel; wake-up effect; Bit error rate; Bit rate; Modems; Modulation; Robustness; Speech; Vocoders;

fLanguage

English

Publisher

ieee

Conference_Titel

Vehicular Technology Conference (VTC Fall), 2013 IEEE 78th

Conference_Location

Las Vegas, NV

ISSN

1090-3038

Type

conf

DOI

10.1109/VTCFall.2013.6692450

Filename

6692450