Fig. 1. Schematic of sampling schemes. (a) ADC full waveform sampling; (b) TOT sampling

Fig. 2. Simulated target and comparison of echo signal using different acquire approaches. (a) Target applied in simulation; (b) normalization curves of mean value of original signal, and signal inferred from TOT width and peak (values are rearranged from small to large)

Fig. 3. Relationship between TOT and peak valueunder different threshold

Fig. 4. Simulation results and corresponding MSE curves with threshold from 0.15 to 0.51. (a)--(j) Reconstruction results of two methods; (k) MSE curves of reconstruction results

Fig. 5. Simulation results and corresponding MSE curves with pulse width from 7 to 44 sampling intervals. (a)--(j) Reconstruction results of two methods; (k) MSE curves of reconstruction results

Fig. 6. Simulation results and corresponding MSE curves with RMSE from 0 to 5.2 sampling intervals. (a)--(j) Reconstruction results of two methods; (k) MSE curves of reconstruction results

Fig. 7. Experimental setup for TOT-based ghost image

Fig. 8. Experimental reconstruction results of ghost imaging. (a) Experimental result applying ADC with 2 GSa/s sampling rate; (b) experimental results applying ADC with 500 MSa/s sampling rate; (c) experimental results applying TOT without peak inverse; (d) experimental results applying TOT with peak inverse

Fig. 9. Reconstruction results of ADC fill wavefrom sampling scheme with different measurement accuracy. (a) 1 bit; (b) 2 bit; (c) 3 bit; (d) 4 bit; (e) 5 bit; (f) 6 bit