1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
Invited Article: Digital beam-forming imaging riometer systems
Rent:
Rent this article for
USD
10.1063/1.3567309
/content/aip/journal/rsi/82/3/10.1063/1.3567309
http://aip.metastore.ingenta.com/content/aip/journal/rsi/82/3/10.1063/1.3567309

Figures

Image of FIG. 1.
FIG. 1.

Beam forming for a Mills cross imaging riometer system. The two small panels on the left show an example of a fan beam formed by a linear array of antennas along the x-axis (top panel) and along the y-axis (bottom panel), respectively. The small inset in the upper right-hand corner of each panel shows the –3 dB outline of the fan beam in plan view. The large panel on the right-hand side depicts the cross-correlation process. Two perpendicular fan beams (shaded) are cross-correlated to produce a narrow pencil beam (solid) pointing in the direction where the two fan beams intersect. The inset shows the –3 dB contour of the pencil beam at the same scale as the other inset diagrams.

Image of FIG. 2.
FIG. 2.

Mills cross block diagram. The total number of antennas actually used is 63, 32 in each arm with one antenna common to both arms. (ARCOM denotes Advanced Riometer Components software.)

Image of FIG. 3.
FIG. 3.

Receiver block diagram. The diplexer provides the mixer with 50 Ω termination to ensure that the intermodulation and port isolation performance is not degraded. (BPF denotes band-pass filter; HPF denotes high-pass filter; LPF denotes low-pass filter.)

Image of FIG. 4.
FIG. 4.

Block diagram of the FPGA processing for the ARIES Mills cross. Filled boxes show stages processed within the FPGA. (ARIES denotes Advanced Rio-Imaging Experiment in Scandinavia. FIFO denotes a first in, first out buffer.)

Image of FIG. 5.
FIG. 5.

Phase maps showing high m number magnetospheric waves at 3.2 mHz on January 17, 2007 05:30 UT. While the IRIS riometer (top panel) can observe the waves, the ARIES riometer (bottom panel) is capable of resolving much greater detail.

Image of FIG. 6.
FIG. 6.

Block diagram of the FPGA processing for the 8 × 8 filled array system. Filled boxes show stages processed within the FPGA. (FIFO denotes a first in, first out buffer.) Reproduced with permission from Imaging Riometer Operations and Data Processing Manual — Andøya, Norway. Copyright 2010 Lancaster University.

Image of FIG. 7.
FIG. 7.

Block diagram of the enhanced FPGA processing for the 4 × 4 filled array system. Filled boxes show stages processed within the FPGA. (FIFO denotes a first in, first out buffer.) Reproduced with permission from Imaging Riometer Operations and Data Processing Manual — Maitri, Antarctica. Copyright 2010 Lancaster University.

Image of FIG. 8.
FIG. 8.

Beam projection of the ARIES Mills cross. The –3 dB beam contours are projected on the ionosphere at 90 km altitude. Only the 556 usable beams are shown, which are numbered left to right, row by row as: 108–117; 138–151; 169–184; 200–217; 231–250; 262–283; 293–316; 325–348; 356–381; 388–413; 420–445; 452–477; 484–509; 516–541; 548–573; 580–605; 612–637; 644–669; 677–700; 709–732; 742–763; 775–794; 808–825; 841–856; 874–887; 908–917.

Image of FIG. 9.
FIG. 9.

Beam projection of the AIRIS 8 × 8 filled array. The –3 dB beam contours are projected on the ionosphere at 90 km altitude. The beam numbers of the inner beams have been omitted for clarity.

Image of FIG. 10.
FIG. 10.

Beam projection for the Maitri Indian Antarctic research station 4 × 4 filled array. The –3 dB beam contours are projected on the ionosphere at 90 km altitude. The large circle shows the wide-beam riometer field of view. The 16 imaging beams are numbered.

Image of FIG. 11.
FIG. 11.

Beam-forming check for the Kilpisjärvi IRIS system. Shown are the 12 beams through which Cassiopeia A passes. The contribution to the received power from Cassiopeia A is shown by solid lines, the modeled values are shown by dashed lines.

Image of FIG. 12.
FIG. 12.

Beam-forming check for the ARIES system. Shown are the 89 beams through which Cassiopeia A passes. The contribution to the received power from Cassiopeia A is shown by solid lines, the modeled values are shown by dashed lines. (ARIES denotes Advanced Rio-Imaging Experiment in Scandinavia.)

Image of FIG. 13.
FIG. 13.

Beam-forming check for the AIRIS system. Shown are the 12 beams through which Cassiopeia A passes. The contribution to the received power from Cassiopeia A is shown by solid lines, the modeled values are shown by dashed lines. (AIRIS denotes Andøya Imaging Riometer for Ionospheric Studies.)

Image of FIG. 14.
FIG. 14.

Beam-forming check for Maitri system. Shown are the six beams through which Sagittarius A* passes. The contribution to the received power from Sagittarius A* is shown by solid lines, the modeled values are shown by dashed lines.

Tables

Generic image for table
Table I.

Comparison of various imaging riometer systems. The first part of the table contains general system specifications. The second part of the table provides information regarding the susceptibility to scintillation, which is dependent upon location, thus details for a specific station are given.

Loading

Article metrics loading...

/content/aip/journal/rsi/82/3/10.1063/1.3567309
2011-03-22
2014-04-18
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Invited Article: Digital beam-forming imaging riometer systems
http://aip.metastore.ingenta.com/content/aip/journal/rsi/82/3/10.1063/1.3567309
10.1063/1.3567309
SEARCH_EXPAND_ITEM