d@n Problem in calculating Peak Search Algorithm for RF Signal targeting ADRV9361-z7035

[FR]

Dear Forum Member,

I implemented a peak search algorithm in HDL targeting platform is ADI ADRV9361-z7035 . Let me first talk about my algorithm.

1-  I am calculating bin from Xilinx FFT core ( 8192 points )

2- Then I slice 32 bit output data coming from FFT into 16 bit slice into I and Q , multiplying I*I and Q*Q and add I2+Q2 . This gave me a scalar magnitude 

3- Then I compare this scalar magnitude with a threshold ( I am giving this from VIO) . and if RF-IN is very strong ( upto -30 dBm) this algorithm give me the correct index but if signal is weaker than -30 dBm then I am getting garbage value and incorrect index

Problem : 

The board is capable to detect weak signal as much as -90dBm as i confirmed by using ADI built-in IIO Oscilloscope  but here I got peak only for very strong signal and garbage and incorrect index for weaker signal .

is there any better way to calculate peak or any suggestion to improve this logic.

 

Best Regards