  The Terahertz (THz) band (0.1-10 THz) has been envisioned as one of the
promising spectrum bands for sixth-generation (6G) and beyond communications.
In this paper, a dual-band angular-resolvable wideband channel measurement in
an indoor L-shaped hallway is presented and THz channel characteristics at
306-321 GHz and 356-371 GHz are analyzed. It is found that conventional
close-in and alpha-beta path loss models cannot take good care of large-scale
fading in the non-line-of-sight (NLoS) case, for which a modified alpha-beta
path loss model for the NLoS case is proposed and verified in the NLoS case for
both indoor and outdoor L-shaped scenarios. To describe both large-scale and
small-scale fading, a ray-tracing (RT)-statistical hybrid channel model is
proposed in the THz hallway scenario. Specifically in the hybrid model, the
deterministic part in hybrid channel modeling uses RT modeling of dominant
multi-path components (MPCs), i.e., LoS and multi-bounce reflected paths in the
near-NLoS region, while dominant MPCs at far-NLoS positions can be deduced
based on the developed statistical evolving model. The evolving model describes
the continuous change of arrival angle, power and delay of dominant MPCs in the
NLoS region. On the other hand, non-dominant MPCs are generated statistically.
The proposed hybrid approach reduces the computational cost and solves the
inaccuracy or even missing of dominant MPCs through RT at far-NLoS positions.
