Presentation shown in IEEE SmartGridComm 2014 by Seppo Horsmanheimo, VTT Technical Research Center of Finland

2. Presentation Outline
1. Background
2. Previous work
3. Urban wireless communications
4. Field trials and results
5. Conclusion and future work

3. Background
• Storm Patrick, which swept over the
Scandinavian peninsula in
26.12.2011.
• The worst storm in 30 years and
caused ~ 60 M€ damages to
energy companies in Finland.
• In some regions, power and mobile
connections were out of order for
two weeks.
• After the storm, Finnish government
tightened regulations concerning
communication and electricity
distribution networks’ reliability.

4. Scope of Electricity Distribution Network
Figure from Viola Systems’ ‘Case Vattenfall: Automating the Distribution Network’ report

5. Network Planning Tool (NPT)
Critical Technologies Towards 5G
ModellingMeasurements
Performance
Assessment
Fault
Simulations

6. Rural Area Field Measurements
Nemo
Outdoor
Viola Arctic
2G/3G

7. Fault Analysis
One feeder down
*) Gray indicates network entities without electricity.
Downlink redundancy rasters
One substation down Several substations down
*) Color indicates the redundancy of 2G networks

8. Modelling of Urban Communication
• Urban mobile networks differ from rural mobile networks
– Networks are capacity limited rather than coverage limited (small cell size)
– Base station antennas are below rooftops or indoors. Buildings, walls, and
ceilings are shadowing the radio signal and causing multi-path effects
– More radio access technologies and operators available
• Mobile operators have taken different strategies in the deployment of
GSM/UMTS/LTE networks.
• Outdoor measurements and available indoor prediction models do not
give an accurate picture about indoor communication conditions (e.g. in
basement).

9. Analysis of Urban Area Grid Communication
Communication
network
3D terrain and
buildings
Coverage prediction fine-tuned
with measurements
Electricity
Network

10. Outdoor Measurements (1/4)
Measured rsrp values and reachable cell counts in LTE network

11. Outdoor Measurements (2/4)
Measured rscp values and reachable cell counts in UMTS network

12. Outdoor Measurements (3/4)
Measured rxlev_full values and reachable cell counts in GSM network

13. Outdoor Measurements (4/4)
Measured rssi values and reachable cell counts in WLAN network

14. Indoor measurements
• Three different types of indoor
environments were selected
– Old vs new building
– First floor vs basement
– Short vs long distance from a
BTS
• A mobile robot was used
indoors to provide the locations
for the measurement samples.
• Lidar and camera was used to
construct a 2D/3D model of
buildings’ interiors.
Critical Technologies Towards 5G

15. Indoor Measurement
Figure. Measurement in GSM, UMTS, LTE and WLAN networks. The red
circles illustrate handover locations.

16. Indoor Coverage (1 / 2)
Ground floorBasement

17. Indoor Coverage (1 / 2)
Ground floor

18. Indoor Coverage (2 / 2)

19. Indoor Coverage (2 / 2)

20. Indoor Coverage (2 / 2)

21. RSRP vs RSRQ in different environments
Indoor
Outdoor

22. Network latency (1 / 4)
• Network latency is one of
the key parameters.
• IEC 61850 standard
defines stringent
requirements for the
latency.
• LTE is reported to fulfill
the classes P4 – P6 (slow
automatic interactions).
Critical Technologies Towards 5G
Picture from Ericsson’s white paper “LTE for utilities”, 2013

23. Network latency (2 / 4)
Critical Technologies Towards 5G

24. Network latency (3 / 4)

25. Network latency (4 / 4)

26. Conclusion
• Operators have taken different strategies to deploy different radio
access technologies (LTE-800/1800, GSM-900/1800, UMTS-
900/2100, and WiFi-2.4/5.0) especially indoors.
• Changes in the radio environment are more vivid in urban areas due
to the shadowing of buildings and the use of lower antenna heights.
• Indoor coverage prediction is challenging. It requires detailed
information about building’s interiors.
• In addition to availability and reliability, latency is also a key
parameter. It is affected by the network load and connection activity.
The mobile network tends to release radio resources if the
connection is not active.

27. Future work
• Performing LTE-800 field trials in rural and urban areas.
• Evaluating latencies with different packet sizes and
transmission intervals.
• Testing GOOSE traffic over a wireless link, and parallel
multi-operator and multi-RAN links to increase reliability.
• Studying new features of LTE (rel 12 and 13) to reduce
latency and to increase reliability and robustness.
– SON (Self-organizing networks) to minimize fault effects
– ProSe (Proximity Services for Public Safety) for reliability
– SDN (Software Defined Networks) for network virtualization

28. Thank you for your time
Any questions?
Seppo.Horsmanheimo@vtt.fi