Sparse phased-array-fed focusing aperture antennas with reduced grating lobes

An electromagnetic antenna comprising:

• a first and second feed element adjacent to each other and configured to simultaneously radiate a first and second signal, the first signal having a first frequency, a first amplitude and a first phase, the second signal having a second frequency, a second amplitude and a second phrase referenced to the phase of the first signal, wherein:
• the first frequency is equal to the second frequency;
• the first amplitude is equal to or larger than the second amplitude by between a factor of −10 dB and 10 dB;
• the first phase is different from the second phase by a predetermined angle between 0 and 360 degrees;
• and
• the first and second feed elements being spaced apart by a predetermined distance between 0.5λ and 1λ, wherein λ is a wavelength of an operating frequency;
• a printed circuit board (PCB) comprising a multi-channel beamforming circuit configured to supply the first and second signals, where the multi-channel beamforming circuit is further configured to transform a third signal into the first and second signal;
• a focal surface on which the first and second feed elements are mounted;
• and
• an electromagnetic lens configured to focus the first and second signals for transmission and/or reception.