Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Linear Approximation in Frequency Domain01:26

Linear Approximation in Frequency Domain

322
Linear systems are characterized by two main properties: superposition and homogeneity. Superposition allows the response to multiple inputs to be the sum of the responses to each individual input. Homogeneity ensures that scaling an input by a scalar results in the response being scaled by the same scalar.
In contrast, nonlinear systems do not inherently possess these properties. However, for small deviations around an operating point, a nonlinear system can often be approximated as linear....
322
Propagation of Uncertainty from Random Error00:59

Propagation of Uncertainty from Random Error

1.6K
An experiment often consists of more than a single step. In this case, measurements at each step give rise to uncertainty. Because the measurements occur in successive steps, the uncertainty in one step necessarily contributes to that in the subsequent step. As we perform statistical analysis on these types of experiments, we must learn to account for the propagation of uncertainty from one step to the next. The propagation of uncertainty depends on the type of arithmetic operation performed on...
1.6K
Distance Measurements by Taping01:18

Distance Measurements by Taping

378
Tapes are essential in surveying for accurate, durable, and short-distance measurements. Made from lightweight, nylon-coated steel, they offer flexibility and strength for rugged outdoor use. The nylon coating protects against rust and wear, extending the tape's life. Standard lengths, around 30 meters, are marked in meters and millimeters for precision.Surveyors select tapes based on site conditions and accuracy needs. Lightweight, nylon-coated tapes are commonly used for ease of handling and...
378
Uniform Depth Channel Flow: Problem Solving01:18

Uniform Depth Channel Flow: Problem Solving

407
To calculate the flow rate for a trapezoidal channel, first, identify the bottom width, side slope, and flow depth of the channel. The cross-sectional area (A) corresponding to the depth of flow (y), channel bottom width (B), and side slope (θ) is determined by:Next, calculate the wetted perimeter, which includes the bottom width and the sloped side lengths in contact with the water. Using the values of the cross-sectional area and the wetted perimeter, determine the hydraulic radius by...
407
Electronic Distance Measuring Instruments01:30

Electronic Distance Measuring Instruments

421
Electronic Distance Measuring Instruments (EDMs) are essential tools in modern surveying, offering precise distance measurements by emitting electromagnetic signals and calculating the time required for these signals to travel to a target and return. Two primary types of signals are used in EDMs — light waves and microwaves — each suited to specific environmental and distance requirements. Light-wave-based EDMs utilize either infrared or laser light, providing high accuracy over...
421
Field Application of Global Positioning System01:28

Field Application of Global Positioning System

272
The Global Positioning System (GPS) has become an indispensable tool in fieldwork, offering unparalleled precision and efficiency for surveying, navigation, and infrastructure development. By harnessing signals from a constellation of satellites, GPS receivers determine the location of objects with remarkable speed and accuracy, often completing calculations within a second.Advantages of Modern GPS TechnologyContemporary GPS receivers are designed to meet the practical demands of field...
272

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Promoting contraceptive use among unmarried female migrants in one factory in Shanghai: a pilot workplace intervention.

BMC health services research·2007
Same author

Apoptosis related protein 3, an ATRA-upregulated membrane protein arrests the cell cycle at G1/S phase by decreasing the expression of cyclin D1.

Biochemical and biophysical research communications·2007
Same author

Efficient one-pot synthesis of highly substituted pyridin-2(1H)-ones via the Vilsmeier-Haack reaction of 1-acetyl,1-carbamoyl cyclopropanes.

Organic letters·2007
Same author

Effects of Andrographitis Paniculata extracts on the expression of CD40 in endothelial cells.

Journal of Huazhong University of Science and Technology. Medical sciences = Hua zhong ke ji da xue xue bao. Yi xue Ying De wen ban = Huazhong keji daxue xuebao. Yixue Yingdewen ban·2007
Same author

Theoretical and experimental investigations on the size of alginate microspheres prepared by dropping and spraying.

Journal of microencapsulation·2007
Same author

Beneficial effects of losartan on vascular injury induced by advanced glycosylation end products and their receptors in spontaneous hypertension rats.

Molecular and cellular biochemistry·2007

Related Experiment Video

Updated: Jan 4, 2026

Calibration of Vector Network Analyzer for Measurements in Radio Frequency Propagation Channels
10:00

Calibration of Vector Network Analyzer for Measurements in Radio Frequency Propagation Channels

Published on: June 2, 2020

22.4K

Kullback-Leibler Divergence Based Probabilistic Approach for Device-Free Localization Using Channel State

Ruofei Gao1,2, Jie Zhang3, Wendong Xiao4,5

  • 1School of Automation & Electrical Engineering, University of Science and Technology Beijing, Beijing 100083, China. g20178585@xs.ustb.edu.cn.

Sensors (Basel, Switzerland)
|November 6, 2019
PubMed
Summary

This study introduces a novel device-free localization (DFL) method using Channel State Information (CSI) uncertainty. The approach enhances indoor localization accuracy by analyzing CSI amplitudes and phases, outperforming existing systems.

Keywords:
Kullback–Leibler divergenceamplitudeschannel state informationdevice-free localizationmultivariate Gaussian distributionphases

More Related Videos

Microfluidic Platform with Multiplexed Electronic Detection for Spatial Tracking of Particles
11:54

Microfluidic Platform with Multiplexed Electronic Detection for Spatial Tracking of Particles

Published on: March 13, 2017

9.7K
Continuous-Wave Propagation Channel-Sounding Measurement System - Testing, Verification, and Measurements
09:36

Continuous-Wave Propagation Channel-Sounding Measurement System - Testing, Verification, and Measurements

Published on: June 25, 2021

3.4K

Related Experiment Videos

Last Updated: Jan 4, 2026

Calibration of Vector Network Analyzer for Measurements in Radio Frequency Propagation Channels
10:00

Calibration of Vector Network Analyzer for Measurements in Radio Frequency Propagation Channels

Published on: June 2, 2020

22.4K
Microfluidic Platform with Multiplexed Electronic Detection for Spatial Tracking of Particles
11:54

Microfluidic Platform with Multiplexed Electronic Detection for Spatial Tracking of Particles

Published on: March 13, 2017

9.7K
Continuous-Wave Propagation Channel-Sounding Measurement System - Testing, Verification, and Measurements
09:36

Continuous-Wave Propagation Channel-Sounding Measurement System - Testing, Verification, and Measurements

Published on: June 25, 2021

3.4K

Area of Science:

  • Wireless Sensing
  • Indoor Localization
  • Device-Free Localization (DFL)

Background:

  • Indoor localization is a key wireless sensing application.
  • Device-free localization (DFL) presents unique challenges compared to device-based methods.
  • Channel State Information (CSI) offers high-granularity physical layer data for localization.

Purpose of the Study:

  • To develop a novel device-free localization (DFL) approach exploiting Channel State Information (CSI) uncertainty.
  • To improve indoor localization accuracy by utilizing CSI amplitudes and phases.
  • To introduce combined fingerprints for enhanced DFL performance.

Main Methods:

  • Constructing CSI-based fingerprints using multivariate Gaussian distributions for amplitudes and phases.
  • Utilizing Kullback-Leibler (KL) divergence for probability calculations between fingerprints and locations.
  • Averaging reference locations weighted by computed probabilities for target localization.

Main Results:

  • The proposed approach demonstrates superior performance compared to Pilot and Nuzzer systems in DFL.
  • Both CSI amplitude and phase fingerprints, as well as combined fingerprints, yield improved localization accuracy.
  • Extensive experiments confirm the efficiency and robustness of the method across various parameters.

Conclusions:

  • Exploiting CSI uncertainty provides an effective strategy for device-free indoor localization.
  • The KL-divergence based method with combined fingerprints offers a promising direction for accurate DFL.
  • The proposed approach represents a significant advancement in wireless sensing for indoor positioning.