A system and method are disclosed by which the effects of time of arrival
errors may be reduced. In a mobile unit, such as a CDMA device, a
correlation pulse is generated when a transmitted code matches a stored
reference code. In the absence of multipath effects, correlation pulses
are generated in response to the detection of multiple transmissions of
the reference code from multiple transmitters. However, multipath effects
distort the generated correlation pulses leading to errors in the time of
arrival measurements. The present invention calculates the width of the
correlation pulses and determines a delay correction factor based on the
pulse width. The delay correction factor is added to the measured delay
time to provide a more accurate delay time, thus permitting more accurate
location measurements based on time of arrival. In alternative
embodiments, other signal factors may also be used to apply delay
correction factors. The actual location determination may be performed by
the mobile unit, or any other positioning determining entity (PDE). The
system is also capable of applying correction factors to time of arrival
signals received from global positioning system (GPS) satellites.