  We propose here a high-frequency spin-Hall nano-oscillator based on a simple
magnetic texture, such as a domain wall, located in an antiferromagnet with
easy-axis anisotropy type. We show that the spin current, polarized along the
anisotropy axis, excites a conical precession of the N\'eel vector in such a
domain wall, which allows obtaining a robust ac output signal, -- contrary to
the planar precession in an uniform uniaxial antiferromagnet, where ac output
is hard to achieve. The frequency of the auto-oscillations is easily tunable by
the applied current up to the THz range, and the threshold current vanishes for
pure uniaxial antiferromagnet. By micro-magnetic simulations, we demonstrate
that the pinning of the domain wall is crucial for the oscillator design, which
can be achieved in nano-constriction layout of the free layer.
