Beaming Day 2023: Live 100m Wireless Power Transfer Demonstration

This demonstration was the following:

The first fractional space based solar power system Proof of Concept demonstration
One power satellite of 1.92m aperture - 6,400 transmitting antenna elements

• One receiving antenna (rectenna) of 1.32m x 1.62m aperture - 1,944 receiving antenna elements

Significant fraction of orbit to ground distance wireless power transfer at 10GHz frequency

• Farfield distance = 2*A^2/γ , A = aperture (m),  γ = Wavelength (m) which is 0.03m for 10Ghz

• 2*1.92^2/0.03 = 246m farfield distance -  so 100m is 41% of farfield and the longest practical distance with apertures constructed in our lab (limited by door size).

• A 385MW, 1130m aperture array is 2*1130^2/0.03 = 85,126km farfield, with a 35,000km orbital altitude is equivalent to the demonstrated distance. 

Safe transfer of received Direct Current power

• Limited by allowable peak microwave intensities to 20% of sunlight

Wireless power beam steering to multiple targets (each 1.92m square) with a fixed transmitter orientation 

• One rectenna

• One light emitting diode antenna array (lectenna wall)

• One radar-absorbing foam thermal target wall