A VHDL-AMS Simulation Environment for an UWB Impulse Radio Transceiver

Ultra-Wide-Band (UWB) communication based on the impulse radio paradigm is becoming increasingly popular. According to the IEEE 802.15 WPAN Low Rate Alternative PHY Task Group 4a, UWB will play a major role in localization applications, due to the high time resolution of UWB signals which allow accurate indirect measurements of distance between transceivers. Key for the successful implementation of UWB transceivers is the level of integration that will be reached, for which a simulation environment that helps take appropriate design decisions is crucial. Owing to this motivation, in this paper we propose a multiresolution UWB simulation environment based on the VHDL-AMS hardware description language, along with a proper methodology which helps tackle the complexity of designing a mixed-signal UWB System-on-Chip. We applied the methodology and used the simulation environment for the specification and design of an UWB transceiver based on the energy detection principle. As a by-product, simulation results show the effectiveness of UWB in the so-called ranging application, that is the accurate evaluation of the distance between a couple of transceivers using the two-way-ranging metho

Energy Detection UWB Receiver Design using a Multi-resolution VHDL-AMS Description

Ultra Wide Band (UWB) impulse radio systems are appealing for location-aware applications. There is a growing interest in the design of UWB transceivers with reduced complexity and power consumption. Non-coherent approaches for the design of the receiver based on energy detection schemes seem suitable to this aim and have been adopted in the project the preliminary results of which are reported in this paper. The objective is the design of a UWB receiver with a top-down methodology, starting from Matlab-like models and refining the description down to the final transistor level. This goal will be achieved with an integrated use of VHDL for the digital blocks and VHDL-AMS for the mixed-signal and analog circuits. Coherent results are obtained using VHDL-AMS and Matlab. However, the CPU time cost strongly depends on the description used in the VHDL-AMS models. In order to show the functionality of the UWB architecture, the receiver most critical functions are simulated showing results in good agreement with the expectations

Performance Analysis of Ultra Wideband Multiple Access Time Hopping – Pulse Shape Modulation in Presence of Timing Jitter

In short-range networks such as wireless personal area networks (WPAN), multiple user wireless connectivity for surveillance would require a wireless technology that supports multiple streams of high-speed data and consumes very little power. Ultra wideband (UWB) technology enables wireless connectivity across multiple devices (users) addressing the need for high-speed WPAN. Apart from having a distinct advantage of higher data rate over Bluetooth v4.0 (24 Mbps), the UWB technology is also found to be tolerant to frequency-selective multipath fading. In this paper authors discuss a time-hopping pulse shape modulation UWB signalling scheme for ad-hoc high bit rate wireless connectivity for defence applications. Authors analyse multiple access interference for both Gaussian channel and frequency selective multipath fading channel to compare the effects of timing jitter on two types of pulse shapes, namely modified Hermite pulse (MHP) and prolate spheroidal wave functions (PSWF). Authors make a comparative analysis of the system performance with respect to PSWF and MHP to ascertain robustness to timing jitter. In the process, authors introduced a new metric of decision factor in timing jitter analysis.Defence Science Journal, Vol. 64, No. 5, September 2014, pp.464-470, DOI:http://dx.doi.org/10.14429/dsj.64.578

Near Real-Time Zigbee Device Discrimination Using CB-DNA Features

Currently, Low-Rate Wireless Personal Area Networks (LR-WPAN) based on the Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 standard are at risk due to open-source tools which allow bad actors to exploit unauthorized network access through various cyberattacks by falsifying bit-level credentials. This research investigates implementing a Radio Frequency (RF) air monitor to perform Near RealTime (NRT) discrimination of Zigbee devices using the IEEE 802.15.4 standard. The air monitor employed a Multiple Discriminant Analysis/Euclidean Distance classifier to discriminate Zigbee devices based upon Constellation-Based Distinct Native Attribute (CB-DNA) fingerprints. Through the use of CB-DNA fingerprints, Physical Layer (PHY) characteristics unique to each Zigbee device strengthen the native bit-level authentication process for LR-WPAN networks. Overall, the developed RF air monitor achieved an Average Cross-Class Percent Correct Classification of %Ctst = 99:24% during the testing of Ncls = 5 like-model BladeRF Software Defined Radios transmitting Zigbee protocol bursts. Additionally, to evaluate the NRT capability of the air monitor, a statistical analysis of Ntiming = 1000 Zigbee bursts determined the worst-case average runtime from burst detection to classification. The analysis concluded that the runtime was truntime fi 269 mSec. Ultimately, this research found that PHY characteristics provide an additional method of authentication NRT to enhance the inherent network security for Zigbee applications from cyberattacks

A Novel Frequency Synchronization Algorithm and its Cramer Rao Bound in Practical UWB Environment for MB-OFDM Systems

This paper presents an efficient time-domain coarse frequency offset (FO) synchronizer (TCFS) for multi-band orthogonal frequency division multiplexing (MB-OFDM) systems effective for practical ultra-wideband (UWB) environment. The proposed algorithm derives its estimates based on phase differences in the received subcarrier signals of several successive OFDM symbols in the preamble. We consider different carrier FOs and different channel responses in different bands to keep the analysis and simulation compatible for practical multiband UWB scenario. Performance of the algorithm is studied by means of bit error rate (BER) analysis of MBOFDM system. We derive the Cramer Rao lower bound (CRLB) of the estimation error variance and compare it with the simulated error variance both in additive white Gaussian noise and UWB channel model (CM) environments, CM1-CM4. Both analysis and simulation show that TCFS can estimate coarse carrier FO more efficiently in UWB fading channels for MB-OFDM applications compared to the other reported results in literature. Also, computational complexity of the proposed algorithm is analyzed for its usability evaluation

Multi-carrier transmission techniques toward flexible and efficient wireless communication systems

制度:新 ; 文部省報告番号:甲2562号 ; 学位の種類:博士(国際情報通信学) ; 授与年月日:2008/3/15 ; 早大学位記番号:新470