DECIM_FACTOR = 8
DUR_INTERVAL = 2.2
FIR_ORDER = 256
L_FIR_BLOCK = 16384
L_PING_PLOT = 100
L_SEARCH = 5000
RECV_PORT = 49152
SEND_PORT = 49152
STOPBAND = 7500
USUAL_FREQS = [25000, 30000, 35000, 40000]