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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Power Delay Profile

RMSDelay = 2.245148e-007 s

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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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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!!!