Assistance with GNU Radio flowgraph troubleshooting

Good Day Sir/Ma'am

I am reaching out to hopefully receive some assistance with my flowgraph. I am trying to detect signal transmissions (Frequency: 148.034 MHz) from very far ranges with my HackRF One and Raspberry pi 4.

I have had success with my flowgraph but now it has been detecting a lot of noise and saving the noise as a signal transmission. This is leading to the collection of unreliable data. I am hoping to implement some sort of dynamic threshold or at least make sure that no noise is detected as a true signal. I tried to implement a frequency xlating filter and moving average and it did help but there is still some noise getting in. I am not sure if my parameters are set correctly or if my flowgraph needs to look different.

To specify:
- The SDR will be moving around into changing noise environments all in one test.

- The SDR and Pi will be in a headless setup, therefore I can't access the flowgraph and adjust thresholds or gains.

- The signal source is transmitting every 3 seconds or so and it has a bandwidth of 4 kHz (148.032 to 148.036 MHz).

- The end goal is to completely eliminate noise from being detected by the SDR, and only detect transmissions from the true signal source.

My custom block (signal strength detector): includes the threshold, cooldown time, and code to save the signal strength to a file only when it has received a value above the threshold. Please let me know if you need a copy of the flowgraph.

Thank you.

Kind Regards