The problem of bandwidth efficient data transmission in multiple antenna or
thogonal frequency division multiplex (OFDM) systems is considered. Contrar
y to the mono-sensor systems, the effects of frequency-selective fading may
be compensated in the multiple antenna systems due to the space diversity
without using a wireless overhead. A modulation scheme that improves the re
liability of data transmission in fading multipath environments and perform
s an accurate channel equalization with no excess bandwidth neither substan
tial training is proposed, The ne cv scheme exploits a frequency domain spr
eading along with the standard OFDM modulation. This modulation yields an i
mproved error rate; its structure is also exploited to estimate the equaliz
er. The problem of reliable channel equalization in such systems is shown t
o be essentially different in single and multiple antenna scenarios. For th
e multiple antenna scenario, a new approach to to robust equalization is pr
oposed, and its performance is analyzed. The numerical study confirms the e
fficiency of the new method in such bandwidth-expensive applications as wir
eless networks.