Authors: Rafi us Shan; Bahram Honary; Hassan Ahmed; David Lund; Michael Darnell
Addresses: School of Computing and Communications, Infolab21, Lancaster University, Lancaster LA1 4WA, UK. ' School of Computing and Communications, Infolab21, Lancaster University, Lancaster LA1 4WA, UK. ' School of Computing and Communications, Infolab21, Lancaster University, Lancaster LA1 4WA, UK. ' HW Communications Ltd., Parkfield, Greaves Road, Lancaster LA1 4TZ, UK. ' HW Communications Ltd., Parkfield, Greaves Road, Lancaster LA1 4TZ, UK
Abstract: Reliability and high quality of service for TErrestrial Trunked RAdio (TETRA) systems are ensured with number of modulation schemes mapped against application requirements. Phase modulation schemes have been extensively used in mobile systems. TETRA-I supports ?/4-differential quaternary phase-shift keying, whereas TETRA-enhanced data services support ?/8-D8PSK along with quadrature amplitude modulation (QAM) schemes to achieve higher data rate. In this paper, performance of phase modulation schemes along with sub-carrier-based QAM-4 over TETRA propagation models is presented. Comparison of performance and complexity of single-carrier and multi-carrier system designs are discussed. Comparison of both designs and modulation schemes over TU-50 and HT-200 channels help to understand the performance of TETRA-II. Implementation efficiency is analysed in terms of message error rate against Es/No over Signalling CHannel, Full size channel for downlink bursts in the 400-MHz TETRA frequency bands.
Keywords: TETRA; terrestrial trunked radio; TEDS; TETRA-enhanced data services; ?/4-DQPSK; ?/8-PSK; QAM-4; physical layer; TU-50; TU-5; HT-200; MER; message error rate; NDB; normal downlink burst; TDMA; time division multiple access; reliability; quality of service; QoS; phase modulation; mobile communications.
International Journal of Vehicle Information and Communication Systems, 2011 Vol.2 No.3/4, pp.269 - 285
Published online: 14 Dec 2011 *Full-text access for editors Access for subscribers Purchase this article Comment on this article