  In this first paper from forthcoming series of works devoted to radio image
of relativistic jets from active galactic nuclei the role of internal structure
of a flow is discussed. We determine the radial profiles of all physical values
for reasonable Michel magnetization parameter $\sigma_{\rm M}$ and ambient
pressure $P_{\rm ext}$. Maps of Doppler boosting factor $\delta$ and observed
directions of linear polarization of synchrotron emission are also constructed.
