Receiving at 1090 MHz

hi all

i’m new to the gnu world , i’m using it in my project , i’m trying to
receive signal from the aircraft at 1090 MHz , unfortunatly i couldnt
recieve i didnt get the preamble , but i used a signal generator in the
uni for the same frequancey and sample period (1 and i received it
correctly (1 micro s) so if any one can help i’ll really appriciate it

the flow graph i used is attached

thank you in advance

anyone have know where can i find eric cottrel code for mose s ads b ?