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SATELLITE 01 COMMUNICATION 03 USEFUL INFORMATION

SATELLITE 02 MONITORING 04 SUMMARY 01 SATELLITE COMMNICATION INCREASINGLY USE OF SATELLITE ORBIT POSITION AND

• Burst requirement on satellite broadband • The satellite orbit position and frequency is limited • Over 1700 satellites are placed • Over 40 countries and organizations have their own satellites

DEVELOPMENT TREND

 Higher frequency • From S/C band to Ku/Ka band

 Larger space station • To carry out applications and experiments in the fields of earth, space application new technology, space technology and space medicine

 Smaller satellite • Lower cost and shorter development period • To carry out research and experience • To provide Internet service and emergency communication to the world

RELATED DEFINITIONS IN REGULATIONS

 Space radiocommunication: Any radiocommunication involving the use of one or more space stations or the use of one or more reflecting satellites or other objects in space

 Satellite link: A radio link between a transmitting earth station and a receiving earth station through one satellite RELATED DEFINITIONS IN RADIO REGULATIONS

 Space station: A station located on an object which is beyond, is intended to go beyond, or has been beyond, the major portion of the Earth's atmosphere RELATED DEFINITIONS IN RADIO REGULATIONS

 Earth station: A station located either on the Earth's surface or within the major portion of the Earth's atmosphere and intended for communication: - with one or more space stations; or - with one or more stations of the same kind by means of one or more reflecting satellites or other objects in space ADVANTAGES

 Large coverage and long distance • Theoretically, 3 GSO satellite could provide satellite communication for the earth ADVANTAGES

• From earth station to satellite • From satellite to earth stations ADVANTAGES

 Complex network structure and safety ADVANTAGES

 Large capacity • • C band: 800 MHz • Ku band: 2050 MHz • Ka band: 2300 MHz • Space division • Applications • Broadcasting • , Iridium • VSAT DISADVANTAGES

 Time delay • 500ms – 800ms

 Rain attenuation • C band: < 2 dB • Ku band: <20 dB

 The Sun Outage • Twice a year, 10 min

 The Eclipse • Twice a year, 5- 10 min period

SATELLITE FREQUENCY

Frequency Frequency range Frequency Frequency range band /MHz band /GHz VHF 30-300 Ku 12.5-18 UHF 300-3000 K 18-26 L 390-1550 Ka 26-40 S 1550-3400 Q 40-46 C 3400-8000 V 46-75 X 8000-12500 W 75-111 SATELLITE SERVICE

 Fixed-satellite service  Broadcasting-satellite service

 Inter-satellite service  Radiodetermination-satellite service

 Space operation service  Radionavigation-satellite service

 Mobile-satellite service  Aeronautical radio navigation-satellite service

 Land mobile-satellite service  Radiolocation-satellite service

 Maritime mobile-satellite service  Meteorological-satellite service

 Aeronautical mobile-satellite service  Earth exploration-satellite service

 Aeronautical mobile-satellite (R) service  Standard frequency and signal-satellite service

 Aeronautical mobile-satellite (OR) service  Amateur-satellite service

SATELLITE CLASSIFICATION

 Function • Scientific satellite • Space physics exploration satellite, Astronomical satellite, Microgravity experimental satellite • SACI, solrad-1, SJ-10 • Technology test satellite • Biosatellite • Applied satellite • Communication satellite: Direct Broadcasting Satellite, • Remote sensing satellite: Meteorological satellites • Navigation satellites: GPS, GLONASS, Galileo, Beidou • Earth resources satellites: SMOS, SMAP, Ocean satellite, Landsat

SATELLITE CLASSIFICATION

 Orbit height

Name of satellite Abbr. Orbit Height Low Earth orbit satellite LEO 200-2000 km Medium Earth orbit satellite MEO 2000-35786 km High Earth Orbit satellite HEO >35786 km Highly Elliptical Orbit satellite HEO Perigee: 1000-21000 km Apogee: 39500-50600 km Geostationary orbit satellite GEO 35786 km SATELLITE TRANSPONDER

 Transparent transponder

 Receive and amplify the signal in the uplink frequency, then retransmit it in the other frequency (downlink frequency)

 Processing transponder

 Receive and demodulate the signal in the uplink frequency, then re-modulate it in the other frequency (downlink frequency)

SATELLITE

 Antenna type

 Parabolic antenna

 Array antenna

 Linear polarization: vertical or horizontal

: right or left SATELLITE BEAM COVERAGE IMPORTANT DEFINITIONS

 EIRP(Effective Isotropic Radiated Power)

 The product of the power supplied to the antenna and the in a given direction relative to an isotropic antenna (absolute or isotropic gain)

 Unit: dBW

 Free space transmission loss

Lp 20log10 (4 d )  20log 10 ( )  32.4  20log 10 ( f )  20log 10 ( d ) dB

 PFD(Power Flex Density) 24  9 10 .2 PFD EIRP  Lpp 10log10 ( )  10log 10 ( BW )  EIRP  L  10log 10 ( )  10log 10 ( BW ) dBW/. m Hz 4 4 f 2

f: , MHz; d: transmission distance, km; BW: bandwidth , Hz

02 SATELLITE MONITORING IMPORTANCE OF SATELLITE MONITORING • Duty 1: Evaluation on satellite resource utilization • Carrier and transponder level • Orbit position occupancy, frequency occupancy • Orbit position and frequency assignment (over long-term usage) • Power Flux Density(PFD) compliance • Beam coverage • Duty 2: Detection and resolution of interference • Detection and technical analysis of interfering satellite communication networks • Geolocation of interfering on the surface of the earth • Determination if the interfering transmitters are mobile or fixed • Duty 3: Identification of unauthorized • Investigation and compliance verification of emission parameters • Identification of unauthorized or improper emissions • Mitigation of the interference

SATELLITE MONITORING OPERATIONS

 Signal reception

 Signal measurement

 Signal identification

 Signal surveillance and alarming

 Geolocation of transmitter on earth

 Ground search and confirmation

 Documentation and database

 Monitoring data visualization

 Statistics and analysis What operations to do

1. Satellite reception

 Acquirement • Antenna system for both GSO satellite and non-GSO satellite • Signal tracking ability

 Expected output • Polarization • Azimuth • Elevation What operations to do

2. Satellite measurement

 Acquirement • Modern receiver to perform real-time, non-real-time (post process) and fixed time period measurements • I/Q data recording

 Expected output • Center frequency • E.I.R.P • Power

• Doppler frequency • C/N0 • PFD • Bandwidth What operations to do

3. Satellite identification

 Acquirement • Post processing and analysis of the signal external and internal parameters • Broadcasting and TV program decoding

 Expected output

• Modulation parameters • Code rate and symbol rate • type • Modulation type • Multiplex Access • Communication system • Coding type • DVB-CID • Communication network type

What operations to do

4. Satellite surveillance and alarming

 Acquirement • Detect an anomaly or unauthorized transmission • I/Q data recording

 Expected output • Center frequency • Guard band noise level changes • Bandwidth • Modulation characteristics • E.I.R.P • Fast spectrograms What operations to do

5. Geolocation of transmitters on earth

 Acquirement • Provide an area where an interfering transmitter is most likely • Whether the interferer is stationary or mobile

 Expected output • Longitude and latitude of the center point of the area • The major axis, minor axis and angle of the area relative to North • Transmitter is stationary or mobile What operations to do

6. Ground search and confirmation

 Acquirement • To positively identify and mitigate an interfering • Terrestrial measurements with AOA, TDOA, FDOA, POA, ID-aided or correlative principles

 Expected output • Longitude and latitude of target transmitter • Operator of the target transmitter What operations to do

7. Documentation and database

 Acquirement • Record monitoring procedures automatically • Long term trend analysis

 Expected output • Operation documentation • Spectrogram and monitoring data • Audio and video information • Test environment data • Work log What operations to do

8. Monitoring data visualization Time spectrum view

 Acquirement

• To build understanding of the performance of a satellite system over time Time view Continuous signal • displaying data in different formats Bursted signal  Expected output

SM.1600-04 • Graphic display of signal data in spatial domain, time domain, frequency domain and modulation domain, i.e. spectrogram, waterfall plot, and constellation diagram • Audio and video display (for previously decoded data) • Geolocation result display • Driving route display of monitoring vehicle What operations to do

9. Statistics and analysis

 Acquirement • To manage the spectrum usage of satellites and earth stations

 Expected output • Status of receiving antennas • Geolocation results of transmitters on earth. • Satellite orbit position occupancy and frequency occupancy • The emergence of new signals, including unauthorized signals. • Identification of authorized/improper/unauthorized emissions. Authorized emissions by known uplink earth stations have proper RF parameters and are approved by the administration. • Deployment of unauthorized satellite communication network What systems to build

System Functions What systems to build

System types

 Fixed monitoring system

 Transportable monitoring system

 Mobile monitoring system

 Aerial monitoring system

 Portable monitoring system EVALUATION OF SATELLITE RESOURCE UTILIZATION

• Measurement on GSO satellite monitoring

• Satellite orbit position measurement

• RF signal measurement

• Signal identification

• Spectrum occupancy measurement

• Unauthorized or improper emissions EVALUATION OF SATELLITE RESOURCE UTILIZATION EVALUATION OF SATELLITE RESOURCE UTILIZATION

• Measurement on non-GSO satellite monitoring

• Satellite finding and tracking

• Orbit position measurement

• RF signal measurement

• Including carrier PFD curve measurement

• Spectrum occupancy measurement

• Signal identification RESOLUTION OF INTERFERENCE Who is interfered

Earth station 1 Satellite transponder 2 RESOLUTION OF INTERFERENCE

 The earth station is interfered RESOLUTION OF INTERFERENCE

 The satellite transponder is interfered RESOLUTION OF INTERFERENCE Geolocation principles • Geolocation of transmitters on Earth using two GSO satellites • TDOA & FDOA • Geolocation of transmitters on Earth using three GSO satellites • TDOA & TDOA

• Geolocation of transmitters on earth using single GSO satellite Source: ITU document, 1C/101 • With inverse Doppler shift • correlation against known transmitters on Earth

Source: ITU document, 1C/101

RESOLUTION OF INTERFERENCE

Satellite Interference issues in 2013-2017 Satellite Interference issues in 2013-2017 600 50 46 47 516 45 500 40 35 400 30 30 24 300 25 22 20 200 15 10 100 5 14 9 2 2 2 1 0 0 2013 2014 2015 2016 2017 IDENTIFICATION OF UNAUTHORIZED TRANSMITTER Measurement principles

• Conventional approaches based on amplitude comparison • Using cross-correlation algorithm for improving system sensitivity • Using aerial monitoring approach for quick detecting of the interference IDENTIFICATION OF UNAUTHORIZED TRANSMITTER • Conventional approaches based on amplitude comparison IDENTIFICATION OF UNAUTHORIZED TRANSMITTER • Conventional approaches based on amplitude comparison

Direction antenna LNA

Omni-direction antenna Parabolic antenna IDENTIFICATION OF UNAUTHORIZED TRANSMITTER • Using cross-correlation algorithm for improving system sensitivity IDENTIFICATION OF UNAUTHORIZED TRANSMITTER • Using aerial monitoring approach for quick detecting of the interference DEPLOYMENT OF NATIONAL SPACE MONITORING NETWORK

Urumqi Beijing China

Shenzhen

46 FACILITIES AND STAFFS

25 3 2 4 9

Staffs Fixed stations Mobile Geolocation Portable stations systems equipment

47 MONITORING COVERAGE

0°E 44°E 180°E

44°E~180°E

Beijing

Shenzhen

48 MONITORING COVERAGE

0°E 44°E 180°E

10°E~180°E

Beijing Urumqi Shenzhen

49 1. Spectrum parameter and occupancy measurement

• Monitoring band • GSO satellite in L/S/X/C/Ku/Ka band • NGSO satellite in L/S/X band

• RF Parameter measurement • Frequency, bandwidth, power, PFD, EIRP, symbol rate and modulation

• Satellite orbit and spectrum occupancy measurement

50 2. Geolocation

• Monitoring band • GSO satellites in C/Ku band • Geolocation principle • TDOA/FDOA algorithm with two satellites • TDOA/TDOA algorithm with three satellites • Geolocation performance • Location accuracy: ≤10km • Operating time: ≤30 min

51 3. Ground search of interference source

• Monitoring band • 230MHz-18 GHz • Monitoring principle • Conventional approaches based on amplitude comparison • In study: Using aerial monitoring approach for quick detecting of the interference

51 03 USEFUL INFORMATION ITU-R ACTIVITIES

• ITU-R initiative • Dealing with assistance in the resolution of cases of harmful interference • Dealing with a request by ITU for the provision of monitoring data in cases of reported interference arising out of coordination issues

• Memorandum of Understanding between Administration and ITU to assist ITU in performing measurements related to cases of harmful interference to space services • 8 monitoring stations are listed in the MoU between 6 administrations • Belarus, China, Germany, Korea, Pakistan, Vietnam INTERNATIONAL MEETINGS

Jun 2018 ITU-R WP1C meeting, Geneva, Switzerland

Oct 2018 The 20th International Space Radio Monitoring Meeting, Oman

Maybe next year International Satellite communication Symposium, Geneva, Switzerland ITU-R DOCUMENTS

• Handbooks • Handbook on Spectrum Monitoring

• Recommendations • SM.1139-0 International monitoring system • SM.1392-2 Essential requirements for a spectrum monitoring system for developing countries • 1C/101 Measurement techniques and new technologies for satellite monitoring

• Reports • SM.2182-0 Measurement facilities available for the measurement of emissions from both GSO and non-GSO space stations WEBSITES

• http://www.satbeams.com/

• http://celestrak.com/

• http://www.itu.int/en/ITU- Source: ITU Source: http://www.satbeams.com/ R/study-groups/rsg1/rwp1c website

Source: ITU website

Source: http://celestrak.com/ 04 SUMMARY HOTSPOTS Evaluation on satellite resource utilization Measurement techniques on GSO satellite monitoring Measurement techniques on non-GSO satellite monitoring Other requirements Detection and resolution of interference Geolocation methods of transmitter on earth (with one, two or three satellites) System requirements and factors affecting geolocation accuracy Useful techniques for each geolocation method Identification of unauthorized transmitter Conventional approaches based on amplitude comparison Using cross-correlation algorithm for improving system sensitivity Using aerial monitoring approach for quick detecting of the interference Other methods