  We propose a simple solution to the uncertain delay problem in USRP
(Universal Software Radio Peripheral)-based SDR (Software-Defined Radio)-radar
systems. Instead of time-synchronization as employed in (pseudo-) passive radar
configurations, which require at least two synchronized receivers, we use
direct reception signal in a single receiver system as a reference to the exact
location of the target echoes. After finding the reference position, reordering
of the echoes is conducted by circular shift so that the reference moved to the
origin. We demonstrate the effectiveness of the proposed method by simulating
the problem on Matlab and implementing a 128 length random code radar on a
USRP. The random code is constructed from zero padded Barker sequence product.
Experiments on measuring multiple echoes of the targets at precise range bins
confirm the applicability of the proposed method.
