Title
Timestamping of IEEE 802.15.4a CSS Signals for Wireless Ranging and Time Synchronization
Abstract
Accurate positioning and distributed time synchronization for short-range personal area networks (PAN) are expected to boost the impact of mobile wireless systems in a variety of applications. At the moment, wireless ranging and time synchronization are often addressed independently. The two main underlying reasons are: 1) the different accuracy requirements for time-of-arrival measurements and local clock correction and 2) the intrinsic difficulty to timestamp the received radio frames with uncertainty lower than some nanoseconds due to the joint effect of clock resolution, wideband noise, clock frequency offsets, and multipath propagation. Of course, if the influence of such phenomena were minimized, time synchronization could benefit from accurate one-way ranging and vice versa. One of the most recent and promising communication schemes to reach this goal is chirp spread spectrum (CSS) modulation. Indeed, this is also one of the alternative physical (PHY) layers for PANs recommended in the amendment IEEE 802.15.4a-2007, recently included in the standard IEEE 802.15.4-2011. In this paper, the features of IEEE 802.15.4a CSS signals for low-level timestamping are analyzed both theoretically and through simulations under the effect of various uncertainty contributions. Accordingly, an effective solution for frame timestamping at the symbol level is proposed. Some experimental results based on a software defined radio implementation of the IEEE 802.15.4a PHY layer confirm that CSS can be successfully adopted both for time synchronization and ranging.
Year
DOI
Venue
2013
10.1109/TIM.2013.2255988
Instrumentation and Measurement, IEEE Transactions
Keywords
Field
DocType
Zigbee,personal area networks,signal processing,synchronisation,CSS modulation,IEEE 802.15.4a CSS signal timestamping,PAN,PHY layers,chirp spread spectrum modulation,clock resolution,distributed time synchronization,local clock correction,mobile wireless systems,personal area networks,physical layers,time synchronization,time-of-arrival measurements,wireless ranging,Chirp modulation,radio distance measurement,synchronization,timing jitter,uncertainty
Timestamping,Synchronization,Computer science,Software-defined radio,Electronic engineering,Real-time computing,Ranging,IEEE 802.15.4a,Clock synchronization,Chirp spread spectrum,Self-clocking signal
Journal
Volume
Issue
ISSN
62
8
0018-9456
Citations 
PageRank 
References 
15
0.85
15
Authors
4
Name
Order
Citations
PageRank
c m de dominicis1435.53
Pivato, P.2150.85
Paolo Ferrari339259.01
Macii, D.4332.38