  We present the end-to-end design of compact passive and lossless metasurface
(MTS) antennas with integrated feeds. The complete low-profile system consists
of a single-layered reactive impedance MTS printed on top of a grounded
dielectric substrate, and is fed by sources which are embedded inside the
substrate. An accurate and efficient volume-surface integral equation-based
model of the device is developed, and used as the basis for the rapid
optimization of its performance. The optimized designs leverage tailored
auxiliary surface waves supported by the impedance MTS to distribute the
localized source power across their apertures. This facilitates the realization
of extreme field transformations such as wide-angle beam-forming or
shared-aperture beam-forming, with nearly 100% aperture efficiencies. The
procedure also allows for arbitrary beam-shaping with complete main beam and
side lobe control. We also derive several feasibility-related constraints,
which can significantly enhance the power efficiency as well as the bandwidth
of the MTS antennas when they are implemented in practice. Full-wave numerical
simulations confirm the effectiveness of the presented approach, as well as the
extreme field transformation capabilities of the synthesized designs.

Applied Physics;Optics