I'm spending some time in understanding L1 PHY development and have some questions on the start of packet detection in an IQ capture
Let's say I have a WiFi IQ capture which consists of 600 packets and want to extract indexes of start and End of each WiFi Packet.
When I plot abs(IQ_samples), it is like
so what I have done is demodulator which gives me the plot ranges between 1 and -1, Since the energy of NULL is very much close to zero compared to the max_value of abs(IQ_sample of each packet).
So my packets have syncwords and Im trying to find the start of my packet by doing cross corelation according to my syncword that every packet have, but the plot of my cross corelation isn't giving me correct plot, it should gives me a high value when there's a syncword found in my demulated IQ samples that data ranges between 1 and -1. My main confusion is why the cross corelation isn't giving me a proper plot to see when my packets starts? I mean proper plot which represents a high value when there's a syncword found in my IQ demodulated samples, else would give me a low value ..
any help please how could I detect the first and the end of my wifi packets? thanks alot.
Im using SDR sampler for sampling ..