How to increase range of PIR sensor

Hi, I want to build a motion sensor by PIR sensor and NCS36000 as its driver. I used the typical circuit in the datasheet of NCS36000 and a Frensel lens,but I have short range (maximum 4m) that PIR can detect motion. How can I increase this range to about 7-8 meters. The range is dependent on what components?! My PIR part number is D203B.
this is the datasheet and typical circuit.

You see that the amplifier gain can be adjusted according to the application.

The achievable range is however mostly limited by sensor noise, the usual means to achieve a wide sensor range is a different (single zone, large aperture) Fresnel lens.