Optical fibre connection

Following on from the recent post about the wireless radio-link connection, there is also the installation of the actual optical fibre. This is connected around the northwest and north edges of the site and is buried into the ground. The following photograph taken last year before any snow fell, shows the digger putting the final stretch of trench in place (very carefully!).


The optical fibre has now been buried into the ground and is secure. The end terminates inside the RF-container and connects us to the outside world.

Network connection

More news from the end of last season! An "out-of-band" network connection was made between the RF-container and the outside world. This provides a low-capacity data stream for administration and service use. It can also be used for low-data-rate tests and other small-scale experiments which are controlled remotely.

Left: The data-link mast is installed. Right: first connection test

The capacity of this link is typically only 3 to 4 Mbits/second, which is only ¹/_1000th of the date output capacity of the site overall. For that, a 4 Gbit/second link would be required, but when installed, that will give KAIRA full data capacity for linking into to EISCAT_3D or even the main LOFAR network.

Connecting services to the barracks

Following on from the previous posting, once the barracks were in place, the services needed to be connected to it. An agricultural-drain was used to make a duct between the RF-container and the barracks. This will carry power, network, grounding and probably some other cables as well. The following photograph was taken during the end of last summer.

The cables need to be buried, not just for protection against the snow, but also vehicles and any animals that might otherwise damage it. Although the barracks is movable and remains on its wheels, it is semi-permanently connected (like a long-term holiday caravan!).

Moving the barracks

With most of the large construction on the HBA finished, we moved the Lehtinen Barracks closer to the RF-container, so it can be used as office space when the HBA summators arrive and we start installing and working on our local signal processing hardware and software.

The final location of the Barracks next to the RF container.

Snow posts

Around the edge of the site, there is some pretty rugged terrain. No doubt for those who were regularly following this web log last year, you will have seen some of the rocky ledges, dips and gullies and other treacherous obstacles. Of course, if you cover this with snow, then it becomes even more dangerous.

At the end of autumn 2011, before the snow became too deep, we went around the site and marked out some of the landscape features with snow posts.


These are made of PVC pipe, that is flexible and can move if hit by severe drifts. They also stand quite tall (which should give you an idea of how deep we could expect some snow falls!). They are also not dangerous if accidentally run into by a vehicle or person. Each one is bright orange for easy visibility against the snow and are taped with reflective strips making them easier to spot in the deep Arctic night.

Securing the ducts

At the end of last year, before the REALLY bitter cold set in, we needed to secure all aspects of the site to ensure that the ice and snow did not get into some of the more fragile areas.

Within the RF-container, there are cable ducts that come up out of the floor of the container lobby, and which contain the signal cables, optical fibre and electrical supply cables. These all need to be protected. For this, a combination of timber, polystyrene and geotextile felt was used to block all holes and provide some shielding.


The above photograph shows the work as it was partially complete. The signal cables are on the right hand side coming up out of the ducts to go into the patch panel.