AFMG Network Forum

zorasch · Member

According to the EASE website, the tail resolution parameter in the AURA response calculation determines "how many ms-bins are used for the particle arrivals". According to the EASE tutorial, this parameter sets "the width of the time boxes (bins) used for the energy distribution of the late part".
I am not exactly sure which of the two descriptions I should follow.
Also, I was wondering if there is a setting that allows the impacts in the late part of the response to be counted individually, i.e. one bin for each impact.
Any suggestions are much appreciated!

Best regards,
Zora

AFMG Pedro Lima · Forum Moderator

Dear Zora,

Both are somehow right, but please let me give you some more insights.

As you might know, AURA calculation engine is a hybrid method method based on Ray Tracing (Cone Tracing) and Image Source Method algorithms. In general we can divide the calculation in two parts:

1. Early part: for the early part, specular reflections are calculated from the Image Source Method, generating more accurate results with regards to time, energy and direction. For this, no bins are used, the timing is precisely determined. This early part also comprehends scattered energy, which is calculated by means of stochastic Ray Tracing, and for this bins are used.

2. Late part: the late part is also calculated by means of stochastic Ray Tracing. The cut-of is determined by the ray order, generating a smooth transition between the early to late part.

That said, the tail resolution sets the bin width (in terms of time) for gathering of energy generated by means of the stochastic Ray Tracing, which is used in both parts of the computation: for the early scattered energy and for the late part.

HTH,