Harmful Interference in Ka-band Satellite Communications: - - PowerPoint PPT Presentation

Harmful Interference in Ka-band Satellite Communications: Regulation vs Technical Advancement

• Dr. Symeon Chatzinotas

Research Scientist in Satellite Communications

3rd Luxembourg Workshop on Space and Satellite Communications Law 5 June 2014, SnT, University of Luxembourg In Collaboration with Shree Krishna Sharma, Sina Maleki, Bjorn Ottersten

1

Outline

• Motivation
• Why Ka-band?

– Considered system and frequency plan

• Sources of possibly harmful interference

– Scenarios A, B, C

• Technical solutions

– Cognitive Radio for SatComs

• Regulatory Challenges
• Conclusions

2

Current Regulatory Regime

• Current status

– Static frequency allocation – Spectrum Segmentation

• Regulate using

– Spectral Masks – Interference Limits

• ITU-R Recommendations

Way Forward…

• Temporal and spatial variations in the spectrum occupancy

– Spectrum holes

• How to exploit without affecting existing services?
• Technical Advancement and/or Spectrum Regulation?

Spectral Coexistence

• Primary - QoS guarantees

– Priority on spectrum utilization – Allows coexistence

• Secondary - No QoS guarantees

– Opportunistic / on-demand access – Does not degrade primary QoS

• Coprimary

– First Come First Served – New services have to protect older Services 5

Digital Divide

• EU Digital Agenda promises

Broadband for All

• 4G networks provide

higher rates to fewer people

• Ka-band broadband

systems

– Wide coverage/bandwidth – Flexible capacity allocation

Illustration by BATS project

6

High-Level System Architecture Aspects

7

Backbone GW Backbone GW

SCC GW1 NCC ISP1 ISP2

NCC : Network Control Center SCC : Satellite Control Center ISP : Internet Service Provider TTC : Telemetry, Tracking & Control

TTC

Ka-band Broadband Interactive

High Throughput Satellite (HTS)

At least one GSO satellite Multi-spot beam w/ frequency re- use Star topology network connecting anchor GWs and user terminals FL: feeder uplink + user downlink

DVB-S2/Sx or similar air interface

RL: user uplink + feeder downlink

DVB-RCS2 or similar air interface

Nominal frequency plan

• Uplink/downlink: 5-times more spectrum

8

LHCP RHCP LHCP RHCP

27.5 30.0 GHz 29.5

FSS Exclusive allocation

17.7

FSS Exclusive allocation

User up link User down link

BSS/FSS Shared allocation FSS Shared allocation FSS Shared allocation

28.25

FSS Shared allocation

17.3 18.7 18.8 19.7 20.2 GHz

Nominal frequency plan

• Uplink: 2-times more spectrum
• Downlink: 5-times more spectrum

9

LHCP RHCP

17.3 20.2 GHz 18.8 18.7

LHCP RHCP

30.0 GHz 29.5 19.7

FSS Exclusive allocation

17.7

FSS Exclusive allocation

User up link User down link

FSS Shared allocation FSS Shared allocation FSS Shared allocation Unccordinated FSS earth station in countries adopting ECC/DEC/(05)01 (updated March 2013)

28.4465 28.9465

Scenario A

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• FSS cognitive satellite terminals reusing frequency bands of
• ther BSS GSO feeder link systems also operating in this band
• Support of satellite terminals on mobile platforms

Cognitive Radio GSO satellite downlink in the Ka-band 17.3-17.7 GHz Harmful interference: Secondary FSS Mitigate using technology

Scenario B

11

• FSS cognitive satellite terminals reusing frequency

bands of FS links with priority protection

• Support of satellite terminals on mobile platforms

Cognitive Radio GSO satellite downlink in the Ka-band 17.7-19.7 GHz Harmful interference: Secondary FSS Mitigate using technology

Scenario C

12

• FSS cognitive satellite terminals reusing frequency

bands of FS links with priority protection

• Support of satellite terminals on mobile platforms

Cognitive Radio GSO satellite uplink in the Ka-band 27.5-29.5 GHz Harmful interference: Primary FS Mitigate using technology Respect interference limits

CoRaSat Vision and Objectives

• CoRaSat vision is a

–

Cognitive Radio Satellite Communications (CoRaSat) system implementing flexible and smart spectrum usage to exploit unused or underused frequency resources assigned to satellite services as primary or secondary allocation.

• CoRaSat aims at enabling its vision by

–

investigating, developing, and demonstrating Cognitive Radio techniques relevant to Satellite Communications systems for dynamic spectrum sharing.

–

providing guidelines for the definition of regulatory, standardization, and technology frameworks for the exploitation of cognitive radio in support of the Digital Agenda for Europe.

Cogni&ve)) Satellite)Link! Primary' Satellite'Link! Primary' Terrestrial'Link! Primary'Link! Cogni&ve)Link!

Incumbent Link Cognitive Link

Incumbent Satellite Link

Cognitive Satellite Link Incumbent Terrestrial Link

Cognitive Radio

• Incumbent User: a (licensed) user who has higher priority or legacy rights on

the usage of a specific part of the spectrum

• Cognitive (or New Entrant) User: an (unlicensed) user who has a lower priority

and is allowed to opportunistically use spectrum assigned to an incumbent user in such a way that it does not cause any unacceptable interference to incumbent users

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−

“ ” “ ”

“ ” “ ” “ y” “c ” “ ” “ ” “ ” “ ”) “ ” “ ”

White Spaces

• Unused Spectrum:

– Time – Frequency

• How to detect, organize and allocate?

– One of the most prominent solutions – Cognitive databases

15 ECC

Databases

• Centralized information

– Geographical data – Services – Policy, Regulation – Historical data – Radio

• Location
• Orientation
• Power
• Antenna

16

Regulatory Challenges

• Regulations to facilitate sharing/trading

– Spectral Databases – How to persuade national regulators to share? – Sensitive information=>Security concerns – Private sector can help: manage DBs, deploy sensors

• Collaboration between national and international authorities

– Terrestrial spectrum at national level, satellite at international – Cross-border coordination

• Dynamic access to government/military exclusive spectrum

– For secondary access – Instant release if needed e.g. public safety scenarios

• Agreement in ITU-R level

17

Conclusions

• Answer resides in the grey area
• Depending on the considered coexistence scenario:

– Technology could possibly enable the spectral coexistence under current regulations – Data sharing by/between national regulators needed to implement the technical solutions – Certain tasks allocated to private companies under proper supervision

• Regulations should facilitate rather than obstruct

technological evolution

18

Thank you! Questions & Discussion

Contact: Symeon.chatzinotas@uni.lu http://www.uni.lu/snt/people/symeon_chatzinotas