Sodankylä Geophysical Observatory |
Specifications
The following are the technical parameters and specifications of the Kilpisjärvi Atmospheric Imaging Receiver Array (KAIRA).Update
Up-to-date technical information on KAIRA, including real-time monitoring data, is now available from the Technical Details pages.General
| Location | Kilpisjärvi |
| Country | Finland |
| Operated by | Sodankylä Geophysical Observatory |
| Receiver Units (RCUs) | 96 |
| Remote Station Processor (RSP) boards | 12 |
| RCU modes used | 0,3,4,5,6,7 |
| RCU modes available, but not used | 1,2 |
| Sample clock frequency | 160 or 200 MHz |
| ADC bits | 12-bit |
| Subbands (frequnecy channels) | 512 |
| Beamlets | transport bit-mode dependent |
Array parameters
The following are the parameters on an array basis. Note that it is possible to mix parts of the array for combined experiments.| Array parameters | LBA | HBA |
| Number of antennas | 48 | 48 |
| Antenna type | Inverted-V dipoles | 16-element tiles |
| Polarisation per antenna | 2 | 2 |
| Array layout | sparse, quasi-random | segmented rectangular |
| Array physical size (approx.) | 34 m diameter | 30 x 50 m |
| Array alignment | symmetrical | 314 degrees |
| Minimum frequency | 10 MHz | 110 MHz |
| Maximum frequency | 90 MHz | 270 MHz |
| RCU modes | RCU3 & RCU4 | RCU5, RCU6 & RCU7 |
| Beam-forming | digital | analogue in each tile digital over array |
| Elevation limit | 20 degrees | 20 degrees |
| Longitude of array centre (deg East) | 20.7620758 | 20.76103311 |
| Latitude of array centre (deg North) | 69.0707445 | 69.0710561 |
| Altitude of array centre (m, Finnish reference) | 493.123 | 495.086 |
| Geocentric-X coordinate (m) | 2136833.225 | 2136818.264 |
| Geocentric-Y coordinate (m) | 810088.740 | 810038.592 |
| Geocentric-Z coordinate (m) | 5935285.279 | 5935299.531 |
See also:
Radar parameters
Because the KAIRA system is often used in conjunction with the EISCAT VHF radar at Ramfjordmoen, near Tromsø, the following information may also be useful.Please note that KAIRA is an independent facility to EISCAT and time allocatedon one facility does not guarantee time on the other
| VHF transmitter direction | 313.95 degress |
| VHF transmitter frequencies | 222.8 - 225.4 MHz |
References:
- KAIRA technical document: KAIRA-SGO-TEC-146
Data products
The following is a rough guide to the sorts of data products that are available. Note that additional facilities might be available for specialised experiments. Potential observers are encouraged to discuss their requirements with the KAIRA team to ensure optimal data for their experiment.| Data product | Ext. | Description |
| Subband statistics | SST | all 512 subbands, min. 1-second integration |
| Beamlet statistics | BST | typically 244 or 488 beamlets, min. 1-second integration |
| Cross correlation statistics | XST | single subband, min. 1-second integration |
| Array covariance cubes | ACC | cross-correlations, stepped subbands, 1s integration only |
| Transient Buffer Board pages | TBB | Transient Buffer Board data |
| Transient Buffer Board raw data | -- | UDP streamed data |
| Beamlet raw data | -- | UDP streamed data |
See also:
- KAIRA Local Pipeline - Lightweight, raw UDP packet recorder
- KAIRA Background Task - Script coordinator for running observations
- KAIRA observing tips - Useful tips and ideas for running a LOFAR station