  Hyperbolic metamaterials were initially proposed in optics to boost radiation
efficiencies of quantum emitters. Adopting this concept for antenna design can
allow approaching long-standing challenges in radio physics. For example,
impedance matching and gain are among the most challenging antenna parameters
to achieve in case when a broadband operation is needed. Here we pro-pose and
numerically analyse a new compact antenna design, based on hyperbolic
metamaterial slab with a patterned layer on top. Energy from a subwavelength
loop antenna is shown to be efficiently harvested into bulk modes of the
metamaterial over a broad frequency range. Highly localized propagating waves
within the medium have a well-resolved spatial-temporal separation owing to the
hyperbolic type of effective permeability tensor. This strong interplay between
chromatic and modal dispersions enables routing different frequencies into
different spatial locations within compact subwavelength geometry. An array of
non-overlapping resonant elements is placed on the metamaterial layer and
provides a superior matching of localized electromagnetic energy to the free
space radiation. As the result, two-order of magnitude improvement in linear
gain of the device is predicted. The proposed new architecture can find a use
in applications, where multiband or broadband compact devices are required.
