DETECTION AND FOCUSING IN MULTITARGET MED IA - TRANSFER-MATRIX METHOD

The iterative time reversal mirror is an efficient tool to focus among a set of targets on the most reflective one. This work provides a met hod to focus on the other targets. It is issued from the theoretical s tudy of the iterative time reversal mirror. The transfer matrix of the system K double bar and the time reversal (TR) operator KK double ba r axe introduced. It is shown that for pointlike targets well resolved by the system, the phase and amplitude law to focus on any one of the targets is given by an eigenvector of the TR operator. The transfer m atrix can easily be measured, then the diagonalization of the TR opera tor provides the number and position of the targets. This result is il lustrated by an experimental example.