Title :
Multi-carrier spread spectrum and its relationship to single-carrier transmission
Author :
Brüninghaus, Karsten ; Rohling, Hermann
Author_Institution :
Inst. of Telecommun., Tech. Univ. Braunschweig, Germany
Abstract :
The combination of orthogonal frequency division multiplexing (OFDM) and code division multiplexing (CDM) has found great interest. In contrast to a conventional OFDM system the information is spread over several subcarriers using orthogonal codes which leads to a diversity gain in frequency-selective channels. In this paper it is shown that such a system is technically equivalent to a single-carrier system with a guard interval if the columns of a Fourier matrix are used as spreading codes. The pros and cons of such a system compared to an OFDM-CDM system with arbitrary spreading matrix are described and discussed
Keywords :
OFDM modulation; diversity reception; matrix algebra; spread spectrum communication; subcarrier multiplexing; Fourier matrix; OFDM system; code division multiplexing; diversity gain; frequency-selective channels; multi-carrier spread spectrum; orthogonal codes; orthogonal frequency division multiplexing; single-carrier transmission; spreading codes; subcarriers; Code division multiplexing; Data communication; Dispersion; Diversity methods; Frequency diversity; OFDM; Radio transmitters; Receivers; Signal processing; Spread spectrum communication;
Conference_Titel :
Vehicular Technology Conference, 1998. VTC 98. 48th IEEE
Conference_Location :
Ottawa, Ont.
Print_ISBN :
0-7803-4320-4
DOI :
10.1109/VETEC.1998.686174
