Title :
Synchronization of a TDMA-OFDM frequency hopping system
Author :
Van de Beek, Jan-Jaap ; Börjesson, Per Ola ; Boucheret, Marie-Laure ; Landström, Daniel ; Arenas, Julia Martinez ; Ödling, Per ; Wilson, Sarah Kate ; Östberg, Christer ; Wahlqvist, Mattias
Author_Institution :
Div. of Signal Process., Lulea Univ. of Technol., Sweden
Abstract :
We present a time division multiple access-orthogonal frequency division multiplexing (TDMA-OFDM)-based radio interface proposal for the Universal Mobile Telecommunication System (UMTS). We focus on synchronization and present an implementable algorithm for the tracking of the mobiles´ time and frequency offsets at the base station in the uplink. This algorithm is based on estimation methods that use redundancy introduced by the cyclic prefix. A modified maximum likelihood (ML) estimator for the additive white Gaussian noise (AWGN) channel is used to meet both the implementational and performance requirements for frequency-selective fading multiuser environments. Simulation results for a typical UMTS mobile channel environment show that the uncoded symbol error rate of a coherently modulated system using our synchronization scheme is virtually indistinguishable from that of a system with no time and frequency offset
Keywords :
AWGN channels; OFDM modulation; error statistics; fading channels; frequency hop communication; land mobile radio; maximum likelihood estimation; multiuser channels; network interfaces; radio links; radio tracking; synchronisation; time division multiple access; AWGN channel; TDMA-OFDM frequency hopping system; UMTS; Universal Mobile Telecommunication System; additive white Gaussian noise channel; algorithm; base station; coherently modulated system; cyclic prefix; estimation methods; frequency offset tracking; frequency-selective fading; mobile channel; modified maximum likelihood estimator; multiuser environments; orthogonal frequency division multiplexing; radio interface; redundancy; simulation results; synchronization; time division multiple access; time offset tracking; uncoded symbol error rate; uplink; 3G mobile communication; AWGN; Additive white noise; Base stations; Frequency division multiplexing; Frequency estimation; Frequency synchronization; Maximum likelihood estimation; Proposals; Redundancy;
Conference_Titel :
Vehicular Technology Conference, 1998. VTC 98. 48th IEEE
Conference_Location :
Ottawa, Ont.
Print_ISBN :
0-7803-4320-4
DOI :
10.1109/VETEC.1998.686447
