PN Acquisition Schemes Using RAKE Structure for DS/SS Systems over a Frequency-Selective Rayleigh Fading Channel
| Paper File | Download Paper File | | Appear In | ECTI Transaction EEC (ECTI Transaction EEC) | | Publication Date | 01/02/2007 - 28/02/2007 | | Volume | 5 | | Pages | 139 - 152 | | No | 1 | | Author 1 | Taweesak Samanchuen | | Author 2 | Sawasd Tantaratana |
Abstract
This paper proposes noncoherent PN acquisition
schemes that combine the hybrid structure, the
RAKE structure, and the double/multiple-dwell tech-
nique in order to improve the performance in a
frequency-selective fading channel. The hybrid struc-
ture reduces the acquisition time compared to a serial
scheme. The RAKE structure enhances the received
signal strength of a multipath faded signal, while the
multiple-dwell technique reduces the acquisition time.
The parallel paths of the hybrid structure are used as
the RAKE ¯ngers as well, avoiding the need of ad-
ditional hardware for the RAKE ¯ngers. To further
improve the performance, noise-only detection is used
in each RAKE ¯nger to nullity the ¯ngers containing
only noise in signal combining of the RAKE struc-
ture. These helps improve the signal-to-noise ratio at
the RAKE output. The performance is evaluated by
analysis and simulation. Results show that the pro-
posed schemes signi¯cantly outperform other nonco-
herent PN acquisition schemes with the similar hard-
ware. |
