1. |
- Gudmundson, Erik, et al.
(författare)
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NQR-Based Explosives Detection—An Overview
- 2009
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Ingår i: ISSCS 2009. - 9781424437849 ; , s. 9-12
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Konferensbidrag (refereegranskat)abstract
- Nuclear quadrupole resonance (NQR) is a radio frequency spectroscopic technique that can be used to detect solid-state compounds containing quadrupolar nuclei, a requirement fulfflled by most high explosives (and narcotics). In this paper, we present an overview of recent research in the detection of explosives using this technique. We also present mathematical models for the data for different acquistion techniques and discuss different state of the art detection algorithms. Finally, we evaluate various algorithms on measured and simulated NQR data.
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2. |
- Gudmundson, Erik, et al.
(författare)
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Spectral Estimation of Damped Sinusoids in the Case of Irregularly Sampled Data
- 2009
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Ingår i: ISSCS 2009. - 9781424437849 ; , s. 97-100
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Konferensbidrag (refereegranskat)abstract
- The problem of estimating a spectral representation of damped sinusoidal signals from a gapped data set is of considerable interest in several applications. In this paper, we propose a new iterative adaptive approach, named dIAA, that provides such an estimate also in the case of irregularly sampled data, a common scenario in, for instance, spectroscopical data measurements. Numerical examples illustrate the benefits of the proposed estimator as compared to typically used methods.
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3. |
- Leonida, Angeliki, et al.
(författare)
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A Digitally Calibrated CT Quadrature Bandpass Sigma Delta ADC for Wimax/LTE
- 2009
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Ingår i: 2009 International Symposium on Signals, Circuits and Systems, ISSCS 2009. - : IEEE. - 9781424437849 ; , s. 105-108
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Konferensbidrag (refereegranskat)abstract
- This paper presents a digitally calibrated Continuous Time Quadrature Sigma Delta ADC for WiMAX/LTE narrow bands. The proposed architecture employs a 5(th) order 2-bit quadrature bandpass Sigma Delta modulator. Dithering and Adaptive Line Enhancement techniques are combined to compensate for mismatch errors in the I/Q paths. The proposed calibration technique introduces no complexity in the ADC design and can be used online. The simulation results show an improvement of 16.75dB in SINAD and 34.42dB in Image Rejection, when a +/- 30% variation in the loop active RC filter coefficients is introduced in the behavioral model.
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4. |
- Morici, Andrea, et al.
(författare)
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A 3.6 mW 90 nm CMOS 2.4 GHz Receiver Front-End Design for IEEE 802.15.4 WSNs
- 2009
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Ingår i: ISSCS 2009. - New York : IEEE. - 9781424437849 ; , s. 77-80
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Konferensbidrag (refereegranskat)abstract
- In this paper a low-power design of an integrated RF receiver for Wireless Sensor Networks (WSNs) in 90nm CMOS technology is proposed. The receiver is IEEE 802.15.4 physical specifications compliant. It is designed to operate in ISM band at 2.45 GHz center frequency. Target devices for this kind of transceiver are low-cost battery powered smart embedded devices and sensors. The receiver is designed to reduce the count of external components in the final system, integrating on silicon the balun for single-ended to differential conversion. The receiver is composed of an inductorless Low Noise Amplifier (LNA), a buffer stage, I and Q passive mixers and Variable Gain Amplifiers (VGAs) that also act as second order filters. A novel integration of balun into the LNA is described. The system is designed to have direct conversion from RF to 6 MHz low-IF. Voltage supply is 1.2 V with a current consumption of 3 mA including necessary biasing networks, and the total power consumption is 3.6 mW. The complete voltage gain is more than 41.5 dB with a Noise Figure (NF) of 12.6 dB. The receiver layout exhibits an area of only 0.12 mm(2). Simulations are provided, including mismatch scenarios.
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5. |
- Rodriguez, Saul, et al.
(författare)
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4G CMOS Nanometer Receivers for Mobile Systems : Challenges and Solutions
- 2009
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Ingår i: ISSCS 2009. - NEW YORK : IEEE. - 9781424437849 ; , s. 73-76
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Konferensbidrag (refereegranskat)abstract
- This paper presents the design challenges and solutions for 4G nanometer radio receivers for mobile devices. The specifications for the ZERO-IF/LOW-IF 4G receiver architecture are derived. Limitations due to the use of low-voltage nanometer technologies are described and novel circuit techniques, such as wideband noise reduction, inductoreless peaking, passive mixing, and low flicker noise amplification are proposed. Finally, a 1.2-V 90nm CMOS receiver front-end for the proposed WiMAX/LTE receiver is designed employing novel circuit techniques. The front-end covers 700 MHz - 6 GHz, providing a total gain of 34 dB, noise figure of 4 dB, flicker noise corner of 10 kHz, and a third order intercept point of -10dBm/0dBm, while consuming a total power of 10.2 mW.
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