  Bow shock pulsar wind nebulae are observed with a variety of complex
morphologies at different wavelengths, most likely due to differences in the
magnetic field strength and pulsar wind geometry. Here we present a detailed
analysis, showing how these differences affect the observational properties in
these systems, focusing on non-thermal synchrotron emission. By adopting
different prescriptions for the local emissivity, on top of the magnetic and
flow patterns taken from 3D high-resolution numerical simulations in
relativistic MHD, and considering various viewing angles, we try to
characterize the main features of the emission and polarization, to verify if
and how these can be used to get information, or to put constraints, on known
objects. We found for example that conditions leading to a strong development
of the turbulence in the bow shock tail produce substantial differences in the
emission pattern, especially in polarized light.
