A radar apparatus has a code generator, a transmission section, a
reception section, a delay section, a despreading processor, a
correlation value detector, a target detector, and an adjustment section.
The transmission section transmits a signal modulated with a spectrum
spread code. The reception section receives a direct wave from the
transmission section and a reflection wave of the transmitted signal from
a target. The delay section delays the despread code stepwise. The
despreading processor performs a despreading processing with respect to a
signal obtained from the reflection wave received, with using the
despread code delayed. The correlation value detector detects a
correlation value from data output from the despreading processor. The
adjustment section adjusts a phase shift between the spectrum spread code
and the despread code so that a correlation strength of the direct wave
is equal to or larger than a predetermined value.