Conference Paper

Synchronisation performance of wireless sensor networks

Authors:
  • Institute for High Perfomance microelectronics and TU-Cottbus
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Abstract

Ultra Wideband (UWB) has been gaining growing research and industry interests in many different areas of wireless communications. Among them using UWB as a radio interface for wireless sensor network is of high interest due to its precise localisation and low power consuming capabilities. In this paper we carry out quantitative analysis into the synchronisation performance of UWB when it operates under usual wireless channel environments. Simulation results confirm that coherent receiver needs around 10 dB less signal to noise ratio to achieve synchronisation compared to the noncoherent detection. Higher spreading factors lead to noticeable improvement for both coherent and noncoherent detection.

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... At the transmitter channel coding, modulation and burst generation are done digitally in the baseband. The ways of implementing the transceiver aimed at power efficient solution are discussed in [2], [3]. ...
... The Conv R-S synchronisation is here obtained with the accuracy of 16 ns as one of the correlators is adopted. The detailed discussion of this synchronisation procedure is given in [3]. Once the receiver is synchronised, data detection is followed by comparing the signal energy at the expected positions on both the first and second half of a symbol. ...
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... As 15 zeros are inserted between the elements of the ternary sequence used for the preamble, one of the correlators can spot it delivering 2 ns accuracy. More detailed treatment of the synchronization algorithm can be found in [3]. ...
... The synchronization algorithm which does correlation and evaluates its result is discussed in [3]. The ASIC chip delivers a synchronization performance comparable to the simulation. ...
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... Since one cycle of 31.2 MHz spans over 16 cycles of 499.2 MHz, this correlation offers effectively 2 ns synchronization accuracy [10]. Beside that I and Q signals are both considered for the synchronization taking into decision the one which delivers the maximum likelihood to the preamble. ...
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An in-depth treatment of impulse an radio ultra-wideband (IR-UWB) wireless system is provided reviewing theoretical background, proceeding with detailed implementation procedure, and finally giving simulation and test results. This is the first research and prototyping work to be published in the field of IR-UWB that operates in the 6–8 GHz band. The aim of this work is to implement an IR-UWB wireless system for industrial automation that is robust and reliable. To achieve this, an analogue bandwidth of 250 MHz and digital baseband processing at the clock frequency 499.2 MHz were realized in a 250 nm
... Moreover, synchronization requirements are relaxed compared to coherent detection [14]. Nevertheless, due to the squaring operation, the synchronization performance degrades [15]. ...
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Wireless sensor networks for industrial communication require high reliability and low latency. Since state of the art wireless sensor networks do not entirely meet these requirements, novel system approaches need to be developed. Ultra wideband communication systems seem to be a promising approach due to the high bandwidth and the resulting robustness against frequency selectivity. Therefore, this paper analyzes the IEEE 802.15.4a impulse-radio ultra-wideband physical layer for the application in wireless sensor networks. The packet error rate for two types of receiver - energy detector and correlation receiver - is evaluated with respect to signal-to-noise ratio. Taking into account regulatory limitations and realistic transceiver characteristics, the maximal achievable coverage range is derived. As a result, the dependency between required reliability of a wireless sensor transmission and the achievable operating distance is given. This upper bound can be used as decision guideline in order to select a suitable system for deployment of a wireless sensor network.
... Analysis of industrial communication systems [5] and our previous simulations [6] have revealed a vulnerability of the preamble. The standard defines the preamble to consist of two parts: the synchronization header (SHR) and the start of frame delimiter (SFD). ...
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