I understand that you seek clarification on possibilities of modifying the radius of Recpetion Sphere in the SBR raytracing method. However to my knowledge, it is not possible.
The reception sphere model surrounds a receiver point with a sphere of varying size. Rays that intersect this sphere are considered reaching the Rx and contribute to the total received power. As correctly stated by you, the radius of the reception sphere depends on the angular separation between the rays and how far the rays have traveled. Because the rays spread out as they leave the Tx, the reception sphere must increase size accordingly.
A correct reception sphere size should guarantee the collection of one ray from each wavefront.
- If it is oversized, more than one ray from the same wavefront adds to the received power.
- If it is undersized, the rays of the same wavefront can be missed altogether.
I hope this helps.
