Fig. 1. Schematic diagram of SISO imaging mechanism

Fig. 2. Diagram of MIMO linear array configuration adopted by the proposed new MIMO mechanism

Fig. 3. Diagram of MIMO linear array configuration adopted by the traditional MIMO mechanism

Fig. 4. Drawing of resolution chart

Fig. 5. Illustration of mannequin

Fig. 6. Reconstructed images (maximum projection) of resolution chart via numerical simulattons (a) SISO array with RMA (b) traditional MIMO array with RMA (c) traditional MIMO array with BPA (d) 1:4:69 MIMO array with RMA (e) 2:3:47 MIMO array with RMA (f) 1:8:35 MIMO array with RMA (g) 1:10:28 MIMO array with RMA

Fig. 7. PSFs of different arrays or different mechanisms for numerical simulations. (a) different arrays. (b) different mechanisms

Fig. 8. Reconstructed images (maximum projection) of mannequin via electromagnetic simulations. (a) SISO array with RMA. (b)1:4:69 MIMO array with RMA

Fig. 9. PSFs of different mechanisms for electromagnetic simulation

Fig. 10. Photograph of vertical scanner

Fig. 11. Schematic diagram and photograph of SISO imaging system (a) Schematic diagram (b) Photograph.

Fig. 12. Measurement of the resolution test chart (a) Photograph (b) Reconstructed image of 1:4:69 MIMO array with RMA (c) Reconstructed image of SISO array with RMA

Fig. 13. Measurement of the child mannequin (a) Photograph (b) Reconstructed image of 1:4:69 MIMO array with RMA