A method and apparatus for DS-CDMA communication having improved timing
resolution. In the transmitter, a signal spread by a first sequence of
pulses is generated with pulse shape given by
##EQU1##
where t is time and T.sub.c is the chip period or pulse width. The pulses
have an auto-correlation function
##EQU2##
In receiver, a second sequence of pulses with pulse shape given by
##EQU3##
is generated. When correlated with the first sequence of pulses the
resulting correlation function is proportional to
##EQU4##
This correlation function narrower peaks than the correlation function
##EQU5##
thereby allowing higher time resolution to be achieved. The correlation
function is achieved by modification of the transmitter or receiver
modulation sequences or by modification of the correlator in the receiver.
