SPACE RADIO MONITORING STATION LEEHEIM. Station Handbook

Transcription

1 SPACE RADIO MONITORING STATION LEEHEIM Station Handbook Issue: November

2 Table of contents 1 Descriptive Specifications of the Space Radio Monitoring Station General Description Functions As an aid for planning and coordination As a tool for satellite positioning and operation Detection of uplink interferers System Characteristics Antenna Antenna Antenna Antenna Antenna Omnidirectional Antennas Computer Controlled Antenna Tracking Antenna Parameters Transmitter Location System (TLS) Reference Transmitter for the TLS Frequency Range Frequency Spectrum Recorder Device For Measurements Below The Noise Floor Measurement Parameters Tasks Spectrum Occupancy Monitoring Position Measurements Interference Measurements Pre-Launch Monitoring Working Hours Contact Address Annexes List...9 Annex 1 Antenna Parameters...10 Annex 2 Request for Measurements...11 Annex 3 Essential Parameters for Transmitter Location...12 Annex 4 Example Frequency Atlas...14 Annex 5a Example Spectrum...15 Annex 5b Example Spectrum...16 Annex 6 Example Spectrum Measured Below the Noise Floor...17 Annex 7 Example Spectrogram of an Emission of a Low Earth Orbiting Satellite...18 Annex 8 Example Sub-Satellite Tracks in the Geographical Grid...19 Annex 9 Example Result of a Transmitter Location Measurement...20 BNetzA, , Nov2008 2

3 1 Descriptive Specifications of the Space Radio Monitoring Station 1.1 General Description The Space Radio Monitoring Station Leeheim belongs to the Bundesnetzagentur für Elektrizität, Gas, Telekommunikation, Post und Eisenbahnen (Federal Network Agency for Electricity, Gas, Telecommunications, Posts and Railways) or in short Bundesnetzagentur / Federal Network Agency. The Agency's responsibilities include spectrum management and spectrum monitoring. The Monitoring Station Leeheim is located at the river Rhine approximately 35 kilometres south-west of Frankfurt/Main. Its full motion antennas of up to 12 metres in diameter are pointed towards satellites in space. These antennas do not serve commercial transmission purposes. They form the heart of an installation used to monitor the frequency spectrum allocated to space radio services and to detect interference on frequencies used for satellite communications. 1.2 Functions As an aid for planning and coordination General orbit observations reveal the actual use of the frequency spectrum for space services. This includes satellite transponder occupancy measurements and the determination of orbital positions in the geostationary orbit. Specific frequency occupancy observations, for example in conjunction with radio frequency coordination procedures, enable potential interference to be detected early during the planning stage of satellite systems. Field experiments can support the optimization of theoretical models that facilitate the shared use of frequencies by space and terrestrial services As a tool for satellite positioning and operation Pre-launch observations on telemetry and tracking frequencies guarantee the successful positioning of geostationary satellites. Monitoring satellite emissions, transponder occupancy and satellite positions is an indispensable tool which enables the competent authorities to check whether a satellites is operated as advance published, coordinated and notified internationally. Interference handling allows sources of harmful interference being detected which otherwise would continue to hinder proper operation of satellite or terrestrial radio services Detection of uplink interferers Cases of up-link interference, i.e. not a satellite is the source of interference but a satellite is the victim, appear more and more. Since users have obtained direct access to satellite capacities, the number of earth stations has risen rapidly. Earth stations are the major source of up-link interference. It can be caused by both technical and operational faults. Illicit uses of satellite transponders and cases of intentional interference to transponders have also been observed. Authorities, operators and users have to cope with this situation. The monitoring system locates interferers by receiving their signals on 2 different paths, i.e. via the interfered satellite and a neighbouring satellite. The time difference and the frequency difference of the signals received at Leeheim are processed to obtain the geographical co-ordinates of the transmitter. As soon as the location of the interferer is known, the interference can normally be swiftly eliminated. BNetzA, , Nov2008 3

4 1.3 System Characteristics Location: 49 51'13" N 08 23'50" E Visible Geostationary Arc: 67 W to 83 E Antenna 4 Antenna 2 Antenna 3 Antenna GHz GHz 130 MHz - 1 GHz GHz GHz GHz Antenna 1 Antenna 1, a 12 m Cassegrain-Beam-Waveguide-Antenna is a broadband antenna designed to cover the GHz frequency range. Rather narrow feeds with optimized characteristics at GHz and GHz as well as at GHz are a pre-requisite for the so-called monopulse tracking for high precision antenna pointing. An adjustable rotary reflector and a slide mounted feed allow switching between the frequency bands. The rather wide GHz frequency slot of Antenna 1 does not allow for monopulse tracking. However, it disposes of accurate computer controlled position tracking capability in all frequency bands Antenna 2 Antenna 2 is a Cassegrain-Antenna with a narrow band feed in the frequency range GHz with a diameter of 8.5 m. This antenna has a limited operational availability at the moment Antenna 3 Antenna 3, consisting of a square of 2.4 m * 2.4 m, is composed of 3 sectors of dipole arrays of different size covering in total the frequency band from MHz. BNetzA, , Nov2008 4

5 1.3.4 Antenna 4 Antenna 4, a 7 m Prime-Focus-Antenna is a multi band antenna covering the range from GHz. This range consists of eight sub-bands each of which overlaps slightly with the neighbouring sub-bands. The corresponding feed systems are partly of cross dipole and partly of horn type. The feed assembly is placed in the focus of the parabolic reflector. The assignment to a certain sub-band is accomplished by rotating the assembly. This is an X-Y-mounted antenna, especially suitable for non-geostationary satellites travelling overhead Antenna 5 Antenna 5, a 3 m Prime-Focus-Antenna with a broadband logarithmic periodic feed GHz, is mainly used in the Ka-Band from GHz. The antenna is mounted as a King-Post-Antenna only for geostationary arc. This antenna is operational in Omnidirectional Antennas The Station disposes also of omni-directional antennas to observe simultaneously all emissions from the sky in a certain frequency band, e.g. of a multi-satellite system. The frequency range is MHz Computer Controlled Antenna Tracking Computer controlled antenna tracking of the Antennas 1, 3 and 4 allows to follow geostationary or non-geostationary satellites by means of the so-called Two Line Elements (TLE) Antenna Parameters A summary of the parameters of the Antennas 1-5 is shown in Annex Transmitter Location System (TLS) The transmitter location system is designed to identify the location of radio transmitters on Earth. The concept is to find the parameters of the triangle between the wanted transmitter and two satellites by means of time and frequency measurements. The system works via two monitoring antennas both operating in the same frequency bands. Either the combination of Antenna 1 with Antenna 4 or of the combination of Antenna 2 with Antenna 4 or of the combination of Antenna 5 with Antenna 4 along with the interfered and an adjacent satellite form the measurement constellation. For transmitter location the input parameters enlisted in Annex 3 are required Reference Transmitter for the TLS The 4 Reference Transmitter units transmit reference emissions for the TLS system and can also be used as a calibrator for the correction for the satellite orbital elements. This permits the performance of self-contained measurements which do not have to rely on possibly insufficient orbital data and external reference emissions. The transmitters can also be operated mobile within Germany. The uplink frequency ranges are: C-Band: MHz, Ku-Band: MHz, K-Band: MHz BNetzA, , Nov2008 5

6 Frequency Range The frequency range of the Station extends from 130 MHz GHz without any gap. TLS operation is limited to frequencies available at the Antennas 1, 2 and 5. They cover all the bands of the Fixed Satellite Service (Space-to-Earth) up to 21.2 GHz. In detail the frequency bands are: / / / / / GHz Frequency Spectrum Recorder The frequency spectrum recorder can be connected to any antenna of the Station. Six frequency bands of up to widths of 100 MHz each can be chosen freely. The spectra of these bands can be scanned quasi simultaneously in a time sharing mode. The result of a registration session is a so-called spectrogram as depicted in Annex Device For Measurements Below The Noise Floor To measure emissions of low power flux densities a monitoring method is available where the noise floor can be suppressed by typically 12 to 15 db. This is achieved by multiple measurements of successive spectra, signal digitizing and processing. This device allows displaying spectra below the noise floor up to 100 MHz wide. An example spectrum is shown in Annex Measurement Parameters The station can measure or determine emission characteristics such as: Frequency Doppler frequency shift Spectrum and bandwidth Class of emission and type of modulation Polarization Power flux density in the reference bandwidth Total power flux density EIRP In case of TV emissions: Sound sub carrier frequencies Coding Program sources etc. Due to sufficient angular velocities of the 4 antennas in azimuth and elevation these parameters can be measured even in conjunction with non-geostationary satellites. The station can measure and record orbital tracks in the frequency range GHz; GHz and GHz with monopulse tracking. BNetzA, , Nov2008 6

7 2 Tasks 2.1 Spectrum Occupancy Monitoring Monitoring the spectrum occupancy means to systematically observe the radio frequency spectrum in order to achieve the following objectives: To identify the basic characteristics of all discoverable emissions from space stations. To determine whether limits are exceeded or whether there are deviations from the internationally published, co-ordinated and/or notified data. To derive the data of the actual occupancy of the frequency bands by space stations. To obtain the data of the actual occupancy of the geostationary orbit positions by space stations. The results are stored in a database and complemented with spectrum prints for each monitored emission or for an assembly thereof. In this format (frequency atlas: Annex 4) the results can be used for comparison with the internationally filed, co-ordinated and notified parameters. These measurements can be done for the geostationary and the non-geostationary orbit. 2.2 Position Measurements In cases where the inclination or ellipticity of a satellite orbit may cause interference to a neighbouring satellite, the trace of the occupied position has to be measured. This is done with monopulse-tracking over a 24 hour period. The trace of the occupied position is given in geographical coordinates (the sub-satellite point) or in a celestial grid: Annex Interference Measurements When interference is reported a clear analysis of the reported data is required. Initial measurements may confirm the report or my require modification of the reported data. In principle, there are two possibilities. Either the source of interference is in space or it is on Earth. In the case the source of interference is in space, there are two possibilities again. Either a known satellite emits a signal not complying with the publication, co-ordination and/or notification, or an unknown satellite is the source. For identification of the interfering source in space, similar measurements are necessary as for occupancy monitoring, although the goal is different. In the case of an interferer on Earth that appears in the downlink of a satellite, transmitter location measurements are required. 2.4 Pre-Launch Monitoring During the pre-phase of the launch of a satellite the frequencies used for telemetry, telecommand and tracking are monitored with respect to the planned orbit. The measurement results facilitate a safer launch and a safer positioning of the satellite. BNetzA, , Nov2008 7

8 3 Working Hours The regular hours of service at Leeheim Monitoring Station are as follows: Mondays to Thursdays 0800 hours hours local time Fridays 0800 hours hours local time Due to flexitime the station may also be manned outside these hours. Leeheim Monitoring Station is not attended on public holidays. 4 Contact Address Bundesnetzagentur Space Radio Monitoring Station Leeheim Satelliten-Messstelle D Riedstadt, Germany During the regular working hours the station can be contacted through the following communication details: phone: fax: Space.Monitoring@BNetzA.de Outside the regular working hours, instructions on how to reach an operator are given on the answering machine. Contact Persons: Klaus Mecher phone: fax: Klaus.Mecher@BNetzA.de Harald Hellwig phone: fax: Harald.Hellwig@BNetzA.de Peter Steiner phone: fax: Peter.Steiner@BNetzA.de BNetzA, , Nov2008 8

9 5 Annexes List Annex 1 Annex 2 Annex 3 Annex 4 Annex 5a/b Annex 6 Annex 7 Annex 8 Annex 9 ANTENNA PARAMETERS Monitoring Station Leeheim Form: REQUEST FOR MEASUREMENT Form: ESSENTIAL PARAMETERS for Transmitter Location Measurements FREQUENCY ATLAS containing a list of measured figures of parameters SPECTRA provided by analysers SPECTRA provided by the device for measurements below the noise floor. SPECTROGRAMS as output from the frequency spectrum recorder SUB-SATELLITE TRACK of a satellite in geographical coordinates Result of a TRANSMITTER LOCATION MEASUREMENT with geographical maps BNetzA, , Nov2008 9

10 Annex 1 Antenna Parameters SPACE RADIO MONITORING STATION LEEHEIM Parameter Antenna 1 Antenna 2** Antenna 3 Antenna 4 Antenna 5*** Frequency Band (GHz) Antenna Type Full Motion Az/El Cassegrain Beam Waveguide Full Motion Az/El, Cassegrain Full Motion Az/El Planar Dipole Array Full Motion, XY-Mount, Prime Focus King-Post Az/El, Prime Focus Antenna Size 12 m Ø 8.5 m Ø 4 m 2 2 m 2 2 m 2 7 m Ø 3 m Ø Polarization LX, LY LX, LY LX, LY LX, LY LX, LY LX, LY LX, LY LX, LY LX LX RHC LX, LX, RHC RHC LX, LY LX, LY LX, LY RHC RHC RHC RHC RHC, RHC LY LY LHC LY LY LHC LHC LHC LHC LHC LHC LHC LHC LX, LY Polarization Adjustment no no yes yes no no yes yes Antenna Gain (dbi) G/T (dbk -1 ) Angle Velocity Az. 16 /s El. 3.5 /s Az. 5 /s El. 5 /s Az. 10 /s El. 10 /s X axle: 3.5 /s Y axle: 3.5 /s Acceleration 10 /s 2 5 /s 2 10 /s /s 2 Antenna Tracking Level Uncertainty rss* Error Frequency Uncertainty Mono- pulse- Track *rss = root sum square ** Limited operational availability ***Operational in 2009 no Mono- pulse- Track Manually, Program-Track 1.6 db (95% Confidence Level) Az. 0.5 /s El. 0.5 /s Manually Manually, Program Track Manually, Program Track Manually not applicable 1.6 db (95% Confidence Level) 1*10-12 (rubidium standard) 1.6 db (95% Confidence Level) not applicable 10

11 Annex 2 REQUEST FOR MEASUREMENTS Addressee: Space Radio Monitoring Submitter : Station Leeheim Name : Date : Time (UTC) : Ref.-Nr. : Mail: Space.Monitoring@bnetza.de Mail : Telephone: Telephone : Telefax: Telefax : URGENT ( YES / NO ) Impact on Service ( YES / NO ) Part A Data of the interferer Name of the station or characteristics which may facilitate the identification Frequency [MHz] Type of transmission Bandwidth [khz] Field strength / power flux density Polarisation Time of interference Other details Further enclosed information (Annex) Remarks: Part B Data on the interfered station Name of the station Assigned frequency [MHz] Type of transmission Bandwidth [khz] Other details (e.g. time of occurrence)) Further enclosed information (Annex) Remarks: 11

12 Annex 3 Essential Parameters for Transmitter Location - Page 1 Interfering Signal Interfered Satellite Interfered Satellite Orbital Data Adjacent Satellite Adjacent Satellite Orbital Data Unit 1 Type of interferer at the time of submission of data: 2 Interferer frequency in the uplink: MHz 3 Interferer polarisation in the uplink: 4 Interferer bandwidth: khz 5 Name of the interfered satellite (as ITU filing): 6 Norad Number of space craft: 7 Nominal orbit position: Degree 8 Satellite operator (responsible for the detailed information): 9 Interfered transponder: Number 10 Centre frequency of transponder in the uplink: MHz 11 Frequency range of transponder in the uplink: MHz 12 Polarization of transponder in the uplink: 13 db-contours of service area in which the interferer is uplinked: Annex No. 14 Centre frequency of transponder in the downlink: MHz 15 Frequency range of transponder in the downlink: MHz 16 Polarization of transponder in the downlink: 17 db-contours of service area in which the interferer is downlinked: Annex No. 18 Epoch as close as possible to the intended measurement date: Date/Time 19 Semi Major Axis: Meter 20 Eccentricity: 21 Inclination: Degree 22 Right Ascension of the Ascending Node (RAAN): 23 Argument of Perigee: Degree 24 either Mean Anomaly: Degree 25 or Longitude at Epoch: Degree 26 Date of next expected orbit manoeuvre: Date/Time 27 Ephemeris Type (Cartesian/Classical/EutelSatOsc/TLE) 28 Coordinate System (ECF/J2000/MeanOfDate/MeanOfEpoch.) 29 Name of the interfered satellite (as ITU filing): 30 Norad Number of space craft: 31 Nominal orbit position: Degree 32 Satellite operator (responsible for the detailed information): 33 Interfered transponder: No. 34 Centre frequency of transponder in the uplink: MHz 35 Frequency range of transponder in the uplink: MHz 36 Polarization of transponder in the uplink: 37 db-contours of service area in which the interferer is uplinked: Annex No. 38 Centre frequency of transponder in the downlink: MHz 39 Frequency range of transponder in the downlink: MHz 40 Polarization of transponder in the downlink: 41 db-contours of service area in which the interferer is downlinked: Annex No. 42 Epoch as close as possible to the intended measurement date: Date/Time 43 Semi Major Axis: Meter 44 Eccentricity: 45 Inclination: Degree 46 Right Ascension of the Ascending Node (RAAN): 47 Argument of Perigee: Degree 48 either Mean Anomaly: Degree 49 or Longitude at Epoch: Degree 50 Date of next expected orbit manoeuvre: Date/Time 51 Ephemeris Type (Cartesian/Classical/EutelSatOsc/TLE) 52 Coordinate System (ECF/J2000/MeanOfDate/MeanOfEpoch.) to be completed Continued on the next page with Reference Station Data BNetzA, , Nov

13 Essential Parameters for Transmitter Location - Page 2 Reference Stations Which transmit continuously in the same uplink coverage and the same transponder as the interferer, with the same polarisation. The antenna diameter should be as small as possible. Reference Stations Reference Stations Unit Reference 1 Reference 2 53 Uplink centre frequency of reference transmission: MHz 54 Bandwidth: khz 55 Type of modulation: 56 Downlink centre frequency via interfered satellite: MHz 57 Downlink centre frequency via adjacent satellite: MHz 58 Antenna diameter: Meter 59 Geographical longitude of the antenna site: 60 Geographical latitude of the antenna site: 61 Geographical information exactly or roughly: 62 Town within which the site is located: 63 Country within which the site is located: Unit Reference 3 Reference 4 64 Uplink centre frequency of reference transmission: MHz 65 Bandwidth: khz 66 Type of modulation: 67 Downlink centre frequency via interfered satellite: MHz 68 Downlink centre frequency via adjacent satellite: MHz 69 Antenna diameter: Meter 70 Geographical longitude of the antenna site: 71 Geographical latitude of the antenna site: 72 Geographical information exactly or roughly: 73 Town within which the site is located: 74 Country within which the site is located: BNetzA, , Nov

14 Annex 4 Example Frequency Atlas OBSERVATION AND MEASUREMENT RESULTS Station identification Position results <1> space station: XYXYXYSAT-1R <110> <190> date of orbital elevation remark monitoring <2> responsible Administration: XYZ position [ ] Leeheim [ ] YYMMDD <3> nominal position: 15,5E 15,5E 32,47 <191> distance [km] signal <115> frequency [MHz] remarks <116> bandwidth emission remarks <117> PFD [dbw] remarks <118> EIRP [dbw] remarks <119> polarisation remarks <131> occupancy spectra YYMMDD:HHMM Annex observation/ registration YYMMDD-MMDD A 2210,000 1M00 O 2210, M , L-X O 2210, M , L-Y A 2218,500 1M00 O 2218, M , L-X O 2218, M , L-Y A 2281,000 1M00 O 2281, M , L-X O 2281, M , L-Y A 2288,000 1M00 O 2288, M , L-X O 2288, M , L-Y A=assigned, M=measured, O=observed, B=assigned beacon; N=no assignment Annex Extract of legend: Generally applicable provisions The term "assigned" is always used if details of the space station observed are recorded in ITU publications and if the measured characteristics can be matched with the published characteristics. This term is used independently of the actual circumstances. If the same position has been assigned to several space stations and.. Meaning of the weighting code Each of the rows comprising the measurement and observation results contains additional columns headed Remarks" after the following columns: <110> Position <115> Frequency <116> Bandwidth of emission and emission characteristics <117> PFD in reference bandwidth <118> EIRP <119> Polarisation <1> Name of space station The name indicated is that specified under <1>. Any unknown space stations are allocated the designation UNKNOWN supplemented with a fictitious nominal position. <2> Responsible Administration <8> Nominal geographical longitude of the geostationary satellite orbit, in degrees. Negative and positive values denote positions to the west and to the east of the Greenwich meridian respectively.. X X X X Fig. 1 End of extract! The legend may extend over several pages as required. 3-digit code group indicating the standard formulation interpreting the measurement result as contained in Annex 1. Origin of the measured value. This is not indicated for a bandwidth measurement value entered under <<116>> since it always originates from an individual measurement. Code M e a n i n g 1 Measured value in general 2 Individual measurement 3 Observation 4 Registration Assigned frequency BNetzA, , Nov

15 Annex 5a Example Spectrum Space Radio Monitoring Station Leeheim Spectrum Analysis Name/Callsign of Station : Example Assigned Frequency : Designation of emission : Readout Analizer [dbm] , , , , , , , , , , ,300 Frequency [MHz] Date, Time : :24:49 [UTC] Analizer: R&S, FSIQ26 Centre Frequency: 12567,300 MHz, Span: 2 MHz Resolution Bandwith: 3 khz, Video Bandwith: 10 khz, Sweep Time: 0,6006 sec Detector: RMS, Trace Operation: Clear/Write BNetzA, , Nov

16 Annex 5b Example Spectrum BNetzA, , Nov

17 Annex 6 Example Spectrum Measured Below the Noise Floor BNetzA, , Nov

18 Annex 7 Example Spectrogram of an Emission of a Low Earth Orbiting Satellite Note: The legend for terms in German language are given in Annex (not attached here) BNetzA, , Nov

19 Annex 8 Example Sub-Satellite Tracks in the Geographical Grid Measured by means of monopulse tracking Visualized from ephemeris data Enlarged BNetzA, , Nov

20 Annex 9 Example Result of a Transmitter Location Measurement GROUND BASED GEOLOCATION REPORT - Page 1 DATE OF REPORT 14/11/ :01 SCENERIO Operational DOCUMENT REFERENCE NUMBER C 203/00011/07 satid System GROUND BASED GEOLOCATION REPORT REPORT ORIGINATOR : satid - System RELATED DOCUMENTS : GEOLOCATION OPERATOR: Monitoring Station Leeheim SESSION REFERENCE : _ASTRA SAMPLE NUMBER : 109 taken on 25/04/2007 at 13:08:16 SAMPLE BANDWIDTH : 300 khz SAMPLERATE: khz SAMPLE LENGTH: Seconds NUMBER OF BLOCKS : 32 LOCATION RESULT (Lat, Lon, or state if not resolved) : N E LOCATION MAP DISPLAY : See attached maps MAIN SATELLITE : Name: ASTRA3A Transponder Number: G21 Orbital Location : 23.5 E Uplink Polarisation: TARGET SIGNAL DETAILS : Satellite: ASTRA3A Uplink Frequency: MHz Tar. DTO: ms Tar. DFO: Hz Tar. SNR: db PREFERENCES: Acq: Number of block: 32 Blocksize: Dsp: Phase correction: ½ Time Width = ½ Frequency Width = Acceleration: Not Applied. Loc: Time search range: Frequency search range: ADJACENT SATELLITE : Name: W2 Transponder Number: F5 Orbital Location : 16.0 E REFERENCE SIGNAL DETAILS : Name: ASTR3A-2 Satellite: W2 Uplink Frequency: MHz Signal Bandwidth: KHz Known Location (Lat, Lon): N E Ref. DTO: ms Ref. DFO: Hz Ref. SNR: db EVENT SUPPORT REQUIRED : (yes/no) Authorised By : (Ops Manager) Event Support Operator : BNetzA, , Nov

21 GROUND BASED GEOLOCATION REPORT - Page 2 Remarks (including spectral plot if available) Transponder Occupation ASTRA-3A (Interfered) EUTELSAT-W2 and ASTRA-1E (Adjacent Satellites) Relative Level [db] Interferer In this area is only temporarily occupancy in the satellite W TLS-Reference- Transmitter Betzdorf TLS-Reference- Transmitter Leeheim Uplink Frequency [MHz] EUTELSAT-W2 (16 E) ASTRA-1E (19,2 E) ASTRA-3A (23,5 E) BNetzA, , Nov

22 GROUND BASED GEOLOCATION REPORT - Page 3 LOCATION RESULT: Köln Area Overview LOCATION RESULT: N E Detail BNetzA, , Nov