The use of sources on satellite with frequencies lower than 10GHz is leading to very large sources and receiver size. An order of magnitude given in most of studies is that at 10GHz, antenna and receiver size should be of the order of 1km for power transmission from GEO. At 1000GHz, the size would be greatly reduced, leading to a 100m emitter/receiver from GEO. However, due to high atmospheric attenuation, the use of sources between 10µm and 10GHz is not possible due to transmission losses. Therefore, there is a large range of possible sources that have not been considered for SPS. Yet, most studies performed are considering a "ground based" receiver close to sea-level. Moreover, in the case of laser sources up to infrared, the presence of clouds of fog will drastically reduce power transmission. In order to reduce or bypass atmospheric limitation, a solution would be to set the receiver higher in a mountain or a very high structure. However, achievable altitudes with structures are not so high and mountains locations are limited . The solution proposed in this proposition is to make use of a tethered airborne receiver. Due to its very high altitude, the airship would receive power with very low atmospheric attenuation. Moreover, due to lower temperatures, receiver heating might be less critical. It would be able to perform "station keeping" using a small part of the received power and would bring down to ground the power through an electric cable. Finally, there would be less of environmental and causality risk such as crossing of the beam by planes or birds, leading to a better acceptability by the population.
