I’ve made some changes to the LoRa Gateway Bridge to make it compatible with the Kerlink iBTS gateway. The iBTS has a slightly different protocol than the “standard” Semtech packet-forwarder, however the changes in LoRa Gateway Bridge are backwards compatible. Basically it will always give you board: 0 and antenna: 0 which makes sense 
This will soon be released, but if you like to test, see https://github.com/brocaar/lora-gateway-bridge/pull/68 for the changes.