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Large peak-to-average power ratio (PAPR) is the major issue in orthogonal frequency-division multiplexing (OFDM) systems. Selective mapping (SLM) has been commonly employed to reduce the PAPR. However, SLM requires side information (SI) which reduce the bandwidth efficiency. A low-complexity cyclic SLM (C-SLM) scheme without SI which uses delay correlation and matched filter, called C-SLM-DC-MF, has...
We describe a “crowd measurement” project, referred to as PoQeMoN, whose main objective is to identify Quality of Service (QoS) indicators in order to predict the Quality of Experience (QoE) for HTTP YouTube content on mobile networks. Results are based on experiments on an operational network. The second contribution of this paper is to show that the proposed indicator is easy to implement in order...
This paper presents a methodology for reducing functional test time in subthreshold SoCs targeting ultra-low power (ULP) internet-of-things (IoT) devices. Due to their low operating speed and voltage, subthreshold SoCs require significantly longer time to test than traditional SoCs. The proposed method models trans-threshold correlations to allow high voltage, high speed testing while accurately predicting...
The objective of this work is to detect delay times between two ultrasonic signals, one of them considered as a reference and the other signal as the signal to be evaluated, using the wavelet transform, to indirectly estimate temperature changes. In this work the evaluation of 3 types of wavelets (Morlet, Mexican Hat and Daubechies 5) was made to detect the delay time in echo ultrasonic signals which...
Time Difference Of Arrival (TDOA) method is very often used inside electronic intelligence systems. TDOA method requires the high signal to noise ratio at the output of the intermediate frequency amplifier for target localization, usually around 12 dB or more. At low signal-to-noise ratio TDOA is inaccurate and especially in case of the active jamming it is nearly impossible. The multilateral TDOA...
In this paper, we study the tradeoff of efficiency and delay of Slepian-Wolf distributed source coding (DSC). In the considered network, Machine-Type Communications (MTC) devices transmit correlated data to one base station, the data sources follow a multi-variate Gaussian distribution. To reduce the consumption of communication resources by massive MTC devices, Slepian-Wolf coding is adopted to eliminate...
Quantum tunneling time is a highly debated topic — we explain why. We discuss the attoclock technique to extracting tunneling delays with regards to the typical approximations such as the dipole approximation, non-adiabatic effects, photoelectron momenta at the tunnel exit, electron correlation and exit coordinate.
Vibration monitoring is thought as an effective tool for the condition monitoring of OLTC used in converter transformer, since the vibration signals are closely related to its mechanical switch-over process from one tap position to another position. Based on the vibration signals measured in some R type OLTC in converter station, phase space reconstruction is used to reconstruct the vibration signals...
In this paper, a waveform design method utilizing the low maximum side-lobe in the synthetic range profile as the criterion for the random hopping frequency radar is proposed. Firstly, the center range ambiguity function which represents matched filtering output of transmitted signal is derived. And the output signal to noise ratios (SNR) of it and the synthetic range profile based on correlation...
The maximum likelihood (ML) estimation for multipath component (MPC) parameters requires high computational complexity, resulting in low efficiency in channel measurement campaigns. In this paper, a new method, called Fast Reduced-Dimension SAGE (FRDS) algorithm, is proposed to estimate the parameters such as excess delay, power, and angle-of-arrival/departure (AoA/AoD). By sounding channels using...
It is straightforward to find ourselves avoiding tasks or situations every day, instead of making an effort to deal with them. This behavior is known as “procrastination”, and it is very common in industrial societies. In the educational context, one of the most likely procrastination situations is the development of a bachelor degree thesis or Master's thesis where the student is supposed to work...
The Over-The-Horizon (OTH) locating of radiation source can be realized by the troposcatter propagation of electromagnetic (EM) signals. This paper studies the troposcatter signal group delay for target ranging and proposes a modified beamspace MUSIC to estimate the arrival azimuth angle of the troposcatter signal. Finally, the OTH target can be located by the ranging and azimuth angle estimation...
In this paper, we describe a 920 MHz band long range wireless SAW passive tag system (WSPTS) for vibration monitoring, which achieves more than 15 m reading distance. For the purpose of structural health monitoring (SHM) of aging infrastructures (e.g. bridge, building, and so forth), passive wireless sensor systems are an attractive option because they are operated battery-less and almost maintenance...
In this paper, we present a new method of constructing Z-complementary pulse trains from sequences with property of Equal Sums of (like) Powers (called ESP sequences) which are resilient to Doppler shifts. Numerical experiments indicate that the proposed Z-complementary pulse trains obtained from ESP sequences have better Doppler resilience than waveforms constructed from the well-known Prouhet-Thue-Morse...
Underwater acoustic communication channels are characterized by a large variety of propagation conditions. Designing a reliable communication system requires knowledge of the transmission parameters of the channel, namely multipath delay spread, Doppler spread, coherence time, and coherence bandwidth. However, the possibilities of its estimation in a real-time underwater communication system are limited,...
In most power analysis attack, power traces obtained from the cryptographic device are aligned using a crypto device based triggering signal. In reality, the attacker does not have the luxury of inserting a trigger in the encryption device source code. This paper aims to execute a CPA attack on an 8 bit PIC-microcontroller (μC) implementation of AES-128 encryption without a crypto μC-based triggering...
Based upon recent results from an air-ground channel measurement campaign, we investigate relationships between three common channel parameters: Ricean K-factor, stationarity distance (SD), and root-mean square delay spread (RMS-DS). Results show that SD and K are positively correlated, SD and dK/dt are negatively correlated, and SD and the temporal derivative of RMS-DS are also negatively correlated.
Radio interferometric techniques have been applied to the tracking of spacecraft and enables precise measurement of the angular positions of spacecraft, stars and other cosmic objects in deep space. The image, or intensity distribution, of a source from the deep space has a Fourier transform that is the two-point correlation function of the electric field, whose components can be directly measured...
Wideband autocorrelation radiometry (WiBAR) is a new method to remotely sense the microwave propagation time τdelay of multi-path microwave emission of low loss layered surfaces such as dry snowpack and freshwater lake icepack. The microwave propagation time τdelay through the pack yields a measure of its vertical extent; thus, this technique is a direct measurement of depth. This technique is inherently...
The fifth-generation (5G) wireless communication systems envision the deployment of massive multiple-input multiple-output (MIMO) technology for enhanced network coverage and capacity. With frequency division duplex (FDD) being the prominent mode of operation, addressing the challenges for massive MIMO systems in FDD is extremely important. One such challenge is the downlink channel estimation, which...
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