Multiband Channel Estimation for Precise Localization in Wireless Networks: Algorithms, Simulations and Experiments

Over the last two decades, we have witnessed a tremendous evolution of wireless communication systems. For example, the data rates in mobile wireless systems have increased from a few tens of kilobits per second to 10 gigabits per second between the first and last, i.e., fifth generation (5G). The main enablers for this growth are signal...

Delay Estimation for Ranging and Localization Using Multiband Channel State Information

In wireless networks, an essential step for precise range-based localization is the high-resolution estimation of multipath channel delays. The resolution of traditional delay estimation algorithms is inversely proportional to the bandwidth of the training signals used for channel probing. Considering that typical training signals have...

Analysis of multipath channel delay estimation using subspace fitting

The presence of rich scattering in indoor and urban radio propagation scenarios may cause a high arrival density of multipath components (MPCs). Often the MPCs arrive in clusters at the receiver, where MPCs within one cluster have similar angles and delays. The MPCs arriving within a single cluster are typically unresolvable in the delay domain....

A survey on machine learning-based performance improvement of wireless networks: PHY, MAC and network layer

This paper presents a systematic and comprehensive survey that reviews the latest research efforts focused on machine learning (ML) based performance improvement of wireless networks, while considering all layers of the protocol stack: PHY,MAC and network. First, the related work and paper contributions are discussed, followed by providing...

A USRP based testbed for wideband ranging and positioning signal acquisition

For validation and demonstration of high accuracy ranging and positioning algorithms and systems, a wideband radio signal generation and acquisition testbed, tightly synchronized in time and frequency, is needed. The development of such a testbed requires solutions to several challenges. Tight time and frequency synchronization, derived from...

Time Delay Estimation from Multiband Radio Channel Samples in Nonuniform Noise

The multipath radio channel is considered to have a non-bandlimited channel impulse response. Therefore, it is challenging to achieve high resolution time-delay (TD) estimation of multipath components (MPCs) from bandlimited observations of communication signals. It this paper, we consider the problem of multiband channel sampling and TD...

Joint Blind Calibration and Time-Delay Estimation for Multiband Ranging

In this paper, we focus on the problem of blind joint calibration of multiband transceivers and time-delay (TD) estimation of multipath channels. We show that this problem can be formulated as a particular case of covariance matching. Although this problem is severely ill-posed, prior information about radio-frequency chain distortions and...

Demonstration of a decimeter-level accurate hybrid optical-wireless terrestrial positioning system

Global Navigation Satellite Systems (GNSS) are nowadays the most common solutions used to cope with Positioning-Navigation Timing (PNT) applications demands. GNSS are relied on in very diverse contexts and domains, yet the interest in systems such as GPS, GALILEO and Beidou is continuously increasing. However, and in particular for safety...

Joint Ranging and Clock Synchronization for Dense Heterogeneous IoT Networks

Synchronization and ranging in internet of things (IoT) networks are challenging due to the narrowband nature of signals used for communication between IoT nodes. Recently, several estimators for range estimation using phase difference of arrival (PDoA) measurements of narrowband signals have been proposed. However, these estimators are based...

Multiresolution Time-of-arrival Estimation from Multiband Radio Channel Measurements

Achieving high resolution time-of-arrival (TOA) estimation in multipath propagation scenarios from bandlimited observations of communication signals is challenging because the multipath channel impulse response (CIR) is not bandlimited. Modeling the CIR as a sparse sequence of Diracs, TOA estimation becomes a problem of parametric spectral...

End-to-End Learning From Spectrum Data: A Deep Learning Approach for Wireless Signal Identification in Spectrum Monitoring Applications

This paper presents end-to-end learning from spectrum data-an umbrella term for new sophisticated wireless signal identification approaches in spectrum monitoring applications based on deep neural networks. End-to-end learning allows to: 1) automatically learn features directly from simple wireless signal representations, without requiring...