EISCAT 3D Site survey Peter Bergqvist Kiruna Tarmo Laakso Sodankylä Lars-Göran Vanhainen Kiruna

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1 EISCAT 3D Site survey 2011 Peter Bergqvist Kiruna Tarmo Laakso Sodankylä Lars-Göran Vanhainen Kiruna

2 Possible new sites Possible new baseline Transmitter site N E Överbygd 68.2 N 14.3 E Kautokeino E3D Design study proposal Transmitter site Tromsö site (Norway) Alternative: Överbygd (Norway) ~67 N Porjus Receiver sites 5 km E Abisko (Sweden) 15 km V Porjus (Sweden) 60 km N Kautokeino (Norway) 50 km N Inari (Finland) The central core (denoted by a green filled circle) is assumed to be located near the present Norwegian EISCAT site at Ramfjordmoen. The dashed circle with a radius of approximately 250 km indicates the approximate extent of the central core FOW at 300 km altitude. Receiving sites located near Porjus (Sweden) and Inari (Finland) provide 3D coverage over the ( ) km height range, while two additional sites near Abisko (Sweden) and Kautokeino (Norway) cover the (70-300) km height range.

3 4 E3D Preparatory Phase Proposed transmitter site locations Tromsö Ramfjordmoen (Norway) Överbygd (Norway) Kautokeino (Norway) Karasjok (Norway) Järämä (Sweden) Kautokeino Överbygd Järämä Sites that have been surveyed in 2011 Surveyed in 2010 Sites to be surveyed by University of Tromsö Porjus

4 Common for the Järämä, Karsjok and Kautokeino areas are. Very sparsely populated. Many locations that are suitable as construction sites. The main activity is reindeer herding

5 Site survey At each location, the search criteria s for a potential antenna site are: For the transmitter site - a 300 by 300 meter area, relatively flat and dry. With possibilities to place smaller interferometry antenna arrays at roughly 120 degrees angular separation and extending out to a distance of about 1 km from the system midpoint. At any point of the area, the maximum horizon elevation angle should not exceed 30 degrees. For the receiving sites - a 300 by 300 meter area, relatively flat and dry, and with an incline of about meters, in the direction towards the transmitter site. The absence of TV/radio transmitters and cell phone base stations in neighborhood. Infrastructure electric power, data communications, etc. Far away from any town/village. Preferably, no houses in sight. the

6 RF survey The site survey field team will perform RFI (Radio Frequency Interference) measurements at the potential EISCAT_3D sites, and collect basic data for the E3D receiver design engineers. The external sources that can interfere with Incoherent Scatter Radar measurements are numerous and include: TV/Radio broadcast. GSM/UMTS base stations. Aeronautical and satellite communication. Radio equipment. Consumer electronics: computers, wireless systems, telephone equipment, etc. Besides these main concerns, secondary concerns as sources of RFI (Radio Frequency Interference) can be high-voltage power lines and motor traffic: snowmobiles, four wheelers, etc. The RF survey includes measurements of the field strength and in-band interference. The field strength measurements aim at locating the strong signals that could potentially cause saturation in the E3D receivers. Strong signals in the antenna sidelobes can also cause intermodulation generated products in the receiver front-end. The in-band interference measurements aim at locating weaker signals, inside the frequency band of interest. Frequency range: 30 MHz 1 GHz

7 RF survey Instrumentation Spectrum analyzer: Rohde& Schwarz FSP7 Omnidirectional antenna: Discone Diamond D-130J, MHz, vertical polarisation Log-Periodic antenna: Create N, MHz Mast 4,5 meter The initial RF survey will be followed by long term RFI-measurements at the selected construction sites.

8 RF survey Wide band antenna (directional) on top of (4,5 meter) mast. Site survey team: Peter Bergqvist, Tarmo Laakso and Lars-Göran Vanhainen Kautokeino Sep 2011

9 Site survey in Järämä, Aug 2011 Recording an area (300 x 300 meter) with a hand-held GPS unit.

10 GPS map: Järämä area1

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12 Karasjok

13 Karasjok. Two areas are recorded at each location.

14 T-DAB MHz

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16 Norwegian Frequency allocation in the VHF band T-DAB = Terrestial digital audio broadcasting MHz Present EISCAT VHF band MHz EISCAT 3D VHF band 230, ,544 MHz T-DAB is not implemented in Sweden and Finland T-DAB EISCAT VHF 225 T-DAB 230 EISCAT 3D 235 T-DAB 240 NATO MHz

17 Kautokeino Foto Kautokeino

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20 Järämä area + Very low RFI levels. A very good place for a remote controlled receiving site or a transmitter site, that is manned only during campaigns Infrastructure, electricity, data communications is lacking. Very remote area, not likely that you can have a permanent staff living here,

21 Karasjok area + Infrastructure - electricity, data communications and roads. Low RFI levels The E3D band (230, ,544 MHz) is inside the T-DAB band (216,0 240,0 MHz)

22 Kautokeino area + Infrastructure - electricity, data communications and roads. Low RFI levels The E3D band (230, ,544 MHz) is inside the T-DAB band (216,0 240,0 MHz)

23 Site locations that have been surveyed Abisko 2005 Porjus 2005 Kautokeino 2005 Inari 2005 Kilpisjärvi Ramfjordmoen 2006 Kilpisjärvi 2010 Järämä Järämä 2011 Karasjok 2011 Kautokeino 2011 Porjus Kilpisjärvi Kautokeino

24 Dinner in Järämä