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A large part of unoccupied licensed spectrum can be vital for many applications and can be accessed opportunistically by Cognitive Radio. Cognitive Radio serves to be a framework for forthcoming 5G communication systems and therefore, extensive research is being carried out in its different domains. The task of sensing spectrum should be efficient and reliable to avoid interference between licensed...
In this paper, we investigate the coexistence problem between Wi-Fi and a pre-standard form of LTE over unlicensed bands, namely, LTE-Unlicensed (LTE-U). We address two coexistence problems. First, the different access mechanisms for Wi-Fi and LTE-U can lead to an increase in the collision rate and higher latency for both systems. We propose a modified Wi-Fi operation mode, whereby Wi-Fi stations...
Channel state information (CSI) is usually necessary for downlink precoding, power allocation, etc. in multiple-input multiple-output (MIMO) systems. When the base stations (BS) are equipped with massive elements, the training overhead required by conventional CSI estimation methods becomes overwhelming, leading to unacceptable loss of spectrum efficiency. In this paper, we investigate pilot design...
In cognitive radio networks, multichannel spectrum sensing yield accurate results compared to single channel sensing schemes. However, often realistic correlation among multiple sensing channels is ignored. In this paper, we investigate the performance of a cognitive radio spectrum sensing systems considering more realistic exponential correlation among multiple sensing channels. Closed-form expressions...
Blind signal search is a technique used in many different types of systems, ranging from cognitive radio to broadcasting applications such as television and radio. A well-known approach used for this, is the Cyclostationary Feature Detection algorithm, which can estimate the baud rate of a detected signal, but is not capable of identifying its position in the spectrum, nor properly analyse spans with...
In this paper we introduce an automated mechanism for knowledge discovery from data streams. As a part of this work, we also present a new approach to the creation of classifiers ensemble based on a wide variety of models. Furthermore, we describe an innovative, highly scalable feature extraction and selection framework designed to work with the MapReduce programming model and the application of designed...
In this paper, a computationally efficient direction of arrival (DOA) estimation algorithm without subspace decomposition is presented with a uniform linear array (ULA). The ULA is divided into two sub-arrays and two noise-free cross-correlation matrices are computed using the data vectors received by the two sub-arrays. By rearranging the elements of a vector formed from the new constructed cross-correlation...
In this paper we describe different procedures to compensate the fixed pattern noise (FPN). These procedures have been developed and tested for a camera designed by us, which is based on a CMOS active pixel sensor (APS). In this kind of sensors, the FPN mainly depends on the noise coming from the column selection electronics. In this sense, we suggest and assess three different methods for FPN compensation:...
This paper describes a joint detection and classification of OFDM/QAM, OFDM/OQAM and SC-FDMA signals, using their cyclic frequency domain profiles of spectral correlation density. Detection and classification are performed by introducing corresponding HMMs of these signals. Some performances of the considered joint detection and classification of these signals, obtained using software simulation models,...
Textile-based sensors are being integrated into garments for the monitoring of physiological signals from the human body. Commonly, textile sensors are implemented through knitting methods, while the response of these sensors from other structures has been less studied. This work analyzed the feasibility of using a textile-based stretch sensor with a coverstitch formation integrated into a commercial...
L2C is the second civilian signal broadcasted on the modernized block of GPS satellites. Compared with L1C/A, the length of L2C code is longer, and includes the civil moderate code (CM code, 20ms) and the civil long code (CL code, 1.5s), which are based on time division multiplexing. For the long CL code, rapid acquisition is difficult due to the large search space. To accelerate the search process...
The topic of probing waveform design has received considerable attention due to its numerous applications in active sensing. Apart from having the desirable property of constant magnitude, it is also anticipated that the designed sequence possesses low sidelobe autocorrelation and/or specified spectral shape. In this paper, the alternating direction method of multipliers (ADMM), which is a powerful...
With the increase in utilization of portable devices and ever-growing demand for greater data rates in wireless transmission, an increasing demand for spectrum channels was observed since last decade. Currently, radio spectrum channels are assigned for quite long time periods to licensed subscribers who may not constantly use these bands, which leads to an inefficient use of the radio spectrum. The...
The proliferation of mobile devices has led to an increasing demand for radio spectrum resources. Currently, the spectrum allocation is static, which has resulted in underutilization of this resource. This situation has motivated the search for solutions to address the spectrum scarcity problem. The channel occupancy rate is a piece of information that can assist the decision making process regarding...
Depression is a serious health disorder. In this study, we investigate the feasibility of depression screening using sensor data collected from smartphones. We extract various behavioral features from smartphone sensing data and investigate the efficacy of various machine learning tools to predict clinical diagnoses and PHQ-9 scores (a quantitative tool for aiding depression screening in practice)...
This study examines the degree to which engineering and science students' personality and demographic characteristics are associated with their leadership practices, an area that few studies have explored. The data was from a sample of 70 students attending two institutions (Massachusetts Institute of Technology [MIT] and the Singapore University of Technology and Design [SUTD]) who participated in...
Object identification is an important task of military Intelligence Surveillance and Reconnaissance (ISR) systems. It plays an integral role during threat detection and situation assessment in the monitored area. This paper considers a ground ISR system comprising distributed Unmanned Ground Sensors (UGS), which perform military vehicle identification based on acoustic signal analysis. Each UGS operates...
A presented paper deals with a theoretical base of the localization of electromagnetic sources. There are presented a mathematical model of localization of electromagnetic sources in near-field region and the mathematical model in far-field region. The localization in far-field region is introduced by covariance matrix and the localization in near-field region is introduced by cross-correlation matrix...
Every student has different learning styles. They have tendency in perceiving, interacting and processing information they have learned. Those tendencies can be identified by assessing stodente' learning styles using the Index of Learning Style (ILS). ILS is commonly used to identify engineering student's learning style in learning personalization system. However, this questionnaire is developed in...
Measuring the velocity of materials that flow through pipelines or vessels in a process plant is a critical need as it can help to control the process as well as to assure an optimum flow condition. There is a wide variety of measurement systems and each design depends greatly on the properties and behaviour of the materials of the investigated flow. The rapid growth of the chemical manufacturing...
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