A Novel Weak Signal Detection Method of Electromagnetic LWD Based on a Duffing Oscillator

Figure 7

System phase trajectory state with different SNR.

(a) No noise ()

(b) Power = 0.1 mW ()

(c) Noise power = 0.5 mW ()

(d) Noise power = 10 mW ()

(e) Noise power = 0.1 mW + test signal

(f) Noise power = 1 mW + test signal

(g) Noise power = 2 mW + test signal

(h) Noise power = 2.8 mW + test signal