Takeshi Manabe and Hitoshi Takai
Superresolution of Multipath Delay Profiles
Measured by PN Correlation Method and Its Application to lndoor Propagation Analyses
Abstract:Time resolution of multipath delay profiles measured by using autocorrelation
of pseudonoise (PN) code sequence is generally limited by the chip
interval of the PN code sequence. In this paper, we propose a superresolution
PN correlation method (SPM) which improves the time resolution of delay
profiles measured by the conventional PN correlation method. The SPM is
based on a decomposition of the eigenvector space of the correlation matrix
delay-profile data vector and gives the number of paths and their delay times
with higher resolution. It is verified by computer simulations and experiments
using coaxial delay lines that the SPM can resolve two paths with a delay
difference of a few tenths of the chip interval. Applicability of the SPM to the
analysis of indoor multipath environment in which many delayed waves arrive
with short delay differences is demonstrated by a indoor radio propagation
experiment at 240 MHz, 910 MHz, and 2.3 GHz.