The University of Southampton
University of Southampton Institutional Repository

Does 16-QAM Provide an Alternative to a Half-Rate GSM Speech Codec?

Webb, W T, Hanzo, L, Salammi, R and Steele, R (1991) Does 16-QAM Provide an Alternative to a Half-Rate GSM Speech Codec? At IEEE VTC'91, United States. 19 - 22 May 1991. , pp. 511-516.

Record type: Conference or Workshop Item (Paper)


The computational complexity, speech-quality, spectral efficiency and robustness trade-offs of speech transmission schemes for personal communications networks (PCNs) are addressed. Differentially encoded star 16-QAM arrangements with and without oversampling and diversity are compared in terms of robustness to the parallel frequency division multiplex (FDM) 16-QAM system to find the most appropriate modern scheme. The 13.4 <i>kbps</i> regular pulse <i>RPE-LTP</i> speech codec is subjected to rigorous bit sensitivity analysis in terms of both cepstral distance (CD) and segmental signal to ratio (SEGSNR) degradations. A twin-class embedded binary Bose-Chaudhuri-Hocqunghem (BCH) bit protection scheme is devised to improve robustness. The 6.2 kBd system proposed guarantees low-complexity, high-quality speech transmissions in a bandwidth of 12 kHz for vehicular speeds of 30 mph and channel signal to ratios (SNRs) in excess of 25 dB, a value readily maintained in microcellular PCNs. Wehn using diversity, our system has similar robustness to the 11.4 kbps quadruple-complexity, lower speech-quality code excited linear predictive speech codec/convolutional coding/minimum shift keying (CELP/CC/MSK) benchmarker utilised. Yes, 16-QAM does provide an attractive alternative to half-rate speech coding.

PDF ww-lh-ras-rs-vtc-1991.pdf - Other
Download (504kB)

More information

Published date: May 1991
Additional Information: Event Dates: 19-22 May 1991 Organisation: IEEE Address: St. Louis, Missouri, USA
Venue - Dates: IEEE VTC'91, United States, 1991-05-19 - 1991-05-22
Organisations: Southampton Wireless Group


Local EPrints ID: 251397
PURE UUID: 3c38de1f-3802-4273-a23b-1404d64f664f

Catalogue record

Date deposited: 14 Sep 2001
Last modified: 18 Jul 2017 10:09

Export record


Author: W T Webb
Author: L Hanzo
Author: R Salammi
Author: R Steele

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton:

ePrints Soton supports OAI 2.0 with a base URL of

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.