IWR6843ISK: How can I make my sensor detect 5 degree each vertically in Vital sign Lab

<Summary>

1. I want my device send wave 5 degree vertically

2. It seems revising the Profile to make device detect further has somewhat error in range.

I know that IWR6843ISK default send chirp 15degree each vertically. 

But I want to make it send the wave 5 degree up and down so I can make powerful wave.

But I cannot find any instructions for that in user_guide.

What I could only find was setting range though.

But It doesn't work that well.

For example, when I set the range as 3.5m to 4.0m it could not detect the sign even I seat 3.7m (in front of the sensor)

But it could detect the sign when I seat about 4.4m

I could not find what seems to be wrong. 

and I am wondering if anybody has these kind of problem too.

thank you.