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The reliability of an indoor localization system is often limited by the capability of the systems of distinguishing the line-of-sight signals in environments with multipath. Besides, estimating the height of the target can be challenging due to dilution of precision (DOP) and non line of sight (NLOS) situations. However, the reflections can be used to infer information about the scenario. We present...
Mobile Communication systems are affected apparently by the Doppler Frequency and Doppler Rate. In multicarrier systems, because of sensitiveness to frequency offset, estimation and compensation are of great importance, which determine system performance directly. In this paper, we consider this problem in FBMC-OQAM system, and based on the property of it, a proper structure of preamble sequence,...
In wireless networks, determining the error bit positions within a packet at the receiver can improve the wireless retransmission efficiency in wireless communications. In this paper, we propose an Error Position Estimating Coding (EPEC) scheme based on Error Estimating Coding (EEC). Specifically, we divide data bits into several groups and indicate the group number individually to implement error...
In this study, two techniques for compensating in-phase/quadrature-phase imbalance (IQI), which are joint estimation and compensation (JEC) and separated estimation and compensation (SEC), have been investigated in the uplink quantized massive MIMO systems. Taking the impacts of both quantization and IQI into consideration, we have expressed the details of the channel estimation and IQI compensation...
Collective Detection (CD) is an interesting technique for acquiring highly attenuated satellites signals in harsh environment. The idea of this approach is to process all signals in view collectively to take advantage of the spatial correlation between GNSS signals as vector acquisition. In this way, the acquisition of weak signals will be facilitated by the presence of stronger ones. Increasing the...
In this contribution, a cyclic-TDOA methodology is simulated. The simulation is a preliminary study that would allow to design and to implement an indoor optical-positioning system relaxing the synchronization requirements among receivers. The synchronism requirement relaxations are carried out by the modification of the structure of the positioning system considering an emitter beacon formed with...
In this paper, we propose a novel algorithm for blind estimation of carrier frequency offset (CFO) in MPSK receivers by using differential constellation trace figures (DCTFs) with application to radio frequency (RF) fingerprint extraction. Due to the quasi-symmetry property of DCTF, carrier frequency offset can be estimated from the orientation of the unique symmetric axis of DCTF through minimizing...
A multi-objective evolutionary algorithm for optimal anchor placement of an infrared indoor positioning system is proposed. As a novel contribution the multipath error, a severe cause of inaccuracies (up to some tens of cm), is taken into account as an objective together with precision in a genetic algorithm. Multipath error and precision of the estimated position are assessed as scalar functions...
A Loran-C system is a hyperbolic navigation system which works based on the TOA methods. The cycle identification and ECD estimation accuracies have considerable effects on the Loran-C system receivers localization accuracy so it is important to estimate the reference point and ECD as precisely as possible. White Gaussian noise degrades the performance of cycle identification and ECD estimation. Also,...
In this paper a beacon-based RF source localization in NLOS condition is proposed. Beacons are used to estimate the obstacle causing the NLOS condition to improve the RF source localization accuracy. The obstacle parameters are estimated using particle filter because of the nonlinearity of the problem. For localization accuracy analysis, Cramer Rao Lower Bound (CRLB) analysis is used. The approach...
Global Navigation Satellite Systems (GNSS) have become an integral part of all applications where mobility plays an important role. However, The performances of GNSS-based positioning systems can be affected in constrained environments (urban and indoor environments), due to masking of satellites by buildings and multipath effects. In this paper, a comparative investigation on classical GNSS localization...
Due to the increasing spread of location-aware applications, developers interest in user location estimation has grown in recent years. As users spend the majority of their time in few meaningful places (i.e., groups of near locations that can be considered as a unique place, such as home, school or the workplace), this paper presents a new energy efficient method to estimate user presence in a meaningful...
The single-carrier frequency-division multiple access (SC-FDMA) or the discrete Fourier transform (DFT) pre-coded orthogonal frequency-division multiple access (OFDMA) technique has been adopted in the uplink transmission of the long term evolution (LTE) terrestrial communication standard, for its lower peak-to-average power ratio (PAPR) and similar receiver complexity, compared with OFDM. It is,...
In Vehicular Ad-hoc Networks (VANETs) communication among vehicles enables new advanced driver assistance systems. Cooperative Awareness Messages (CAMs) are so frequently exchanged that deployable electronic control units will not be powerful enough to process them all. Thus, most relevant CAMs need to be selected for processing. In this paper, we give an overview of relevance estimation function...
Results of estimation of required levels of radiated power of base stations of cellular communications at the voice communication mode on urban area, taking into account attenuation of radio waves in buildings, and levels of intranetwork interference, are resulted. Analysis is made on the basis of behavior simulation of the fragment of GSM network at voice communication mode, executed with the use...
The Data Over Cable Service Interface Specification (DOCSIS) provides internet access via cable TV networks. The latest version 3.1 replaces the Physical Layer of previous DOCSIS versions. With DOCSIS 3.1, broadband cable network operators want to accelerate their networks to gigabit-per-second speeds. Enhancements include an increased bandwidth per downstream channel of up to 192MHz, Orthogonal Frequency-Division...
Inter-cell interference is the main obstacle for increasing the network capacity of Long-Term Evolution Advanced (LTE-A) system. Interference Cancellation (IC) is a promising way to improve spectral efficiency. 3rd Generation Partnership Project (3GPP) raises a new research project — Network-Assisted Interference Cancellation and Suppression (NAICS) in LTE Rel-12. Advanced receivers used in NAICS...
In this paper, the clipping noise estimation problem based on compressed sensing (CS) is investigated when the subcarriers used for creating measurement vector are on the edge of the frequency band. Although selection of such subcarriers would not degrade data rate and is suitable for systems requiring high rates, it still weakens the performance of CS recovery algorithms especially in the presence...
Vehicular traffic congestion is a major problem all over the world with significant economic and environmental impact. Adapting traffic signal durations is one method to alleviate this problem and has the advantage that it does not require any significant changes to existing infrastructure such as traffic poles and roads. Reinforcement learning is suitable for adapting the traffic signal durations...
We consider the problem of angle-of-arrival (AoA) estimation of a RF transmitter using a mobile receiver. We develop a method very similar to synthetic aperture radar which is compatible with cellular technology. By considering the successive packets received along the receiver trajectory, we implicitly create a virtual MIMO array, which allows us to utilize conventional MIMO theory for AoA estimation...
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