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Requirements of wireless systems in industrial areas
Javier Ferrer-Coll, Per Ängskog, José Chilo, Peter Stenumgaard
Center for RF Measurement Technology, University of Gävle,Sweden
Outline
IntroductionElectromagnetic InterferenceMultipath MeasurementsPropagation LossOverallConclusion
Introduction
Commercial wireless applications face problems:◦ Electromagnetic Interference◦ ISI Multipath Effects◦ Coverage Propagation Loss
It is needed to characterize the environment before to deploy a wireless system measurements, simulations.
Measurements campaign conducted at multiple industrial environments:◦ Steel Mill◦ Paper Warehouse◦ Rail Yard
Electromagnetic characterization from 20 MHz to 3 GHz.
ELECTROMAGNETIC INTERFERENCE
Electromagnetic Interference
Impulsive and Gaussian noise have different statistical properties.
Detect and calculate the impact of impulsive interference in communication systems.
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Samples
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Impulsive Noise
Gaussian Noise
Simulation of BPSK system with Gaussian and Impulsive noise.
Electromagnetic Interference
Measurements of radio interference in railway transport.◦ Marshalling yard: Remote control
locomotive technologies.
Electromagnetic Interference
Reference measurement
Train with heavy load
Electromagnetic Interference
Analysis of the interference◦ Broadband frequency scan◦ Time measurement at particular frequency◦ Statistical analysis
MULTIPATH MEASUREMENTS
ISI (Inter-Symbol Interference)
Multipath Measurements
Time dispersion can produce ISI.Where can we expect problems?
Quantify
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PD
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Power Delay Profile
RMSDelay = 2.245148e-007 s
Ts Ts
High-Reflective High-Absorbent
Multipath High-Reflective to Absorbent
90% of the received energy arrives at: 10 ns for high-absorbent 148ns for office 664ns for high-reflective
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Delay [s]
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High AbsorbingOffice environmentHigh Reflective
PROPAGATION LOSS
Propagation Loss
LoS measurements in Reflective and Absorbent environment.
Stronger small scale fading for Reflective.
Propagation Loss
LoS High Reflective
NLoS High Reflective
LoS High Absorbing
NLoS High Absorbing
Path Loss Exponent
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Overall Interference vs Time Dispersion
Low level of interference provides the best performance of wireless systems
High reflectivity can produce ISI but low reflectivity can insert coverage problems
Conclusions
Impulsive noise are different than Gaussian.
Electrical motors, vehicles and repair work insert impulsive interference in wireless systems.
Different industrial environments have different propagation characteristics (Reflective, Absorbent).
There is not a single best solution for all industrial cases.
THANK YOU!!!