A Spectrum-Efficient Cross-Layer RF Distance Bounding Scheme

Figure 9

The simulation results of SFCW ranging and challenge-response communication. (a) The SFCW frequency in the time domain (C = 1). (b) The SFCW frequency in the time domain (C = 0). (c) The SFCW waveform segments @ 620 MHz, 820 MHz, 1020 MHz. (d) The SFCW waveform segments @ 1120 MHz, 920 MHz, 720 MHz. (e) The 100 kHz ASK baseband signal. (f) The ASK modulation on the SFCW signal. (g) The ASK bits demodulated by the envelope detector. (h) The IF signal (about 50 kHz) after the down-conversion. According to (2), the _ is about 50 ns. (i) The Curve of IFFT result. The LOS pulse arrives when n equals 25. According to (15), we get the _ = 50 ns.

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

(i)