| 摘要 |
A bidimensional imaging system by echoes including a transmitting array and a receiving array. The transmitting array includes a row of transmitters (E1, E2, . . . , Ei, EN) parallel to a direction Oz and the receiving array includes a row of receivers in a direction Ox. All the transmitters simultaneously transmit signals with different codes. The signals received are demodulated and the real and imaginary components of these signals are applied to two multiplexing circuits (61.1, 61.2). After modulation the multiplexed signals are applied to a Fourier transformation circuit (63), which sequentially supplies reception channels Vk( theta k) for the direction referenced by angle theta k and which are stored in memories (66.1, 66.2). Other memories (70.1, 70.2) contain signals Si( phi i) transmitted in an angular direction referenced by phi i. The two pairs of memories (66.1, 66.2 and 70.1, 70.2) are connected and the signals are applied after modulation to a convolver (61), which supplies signals of the bidimensional image. The imaging system has application to ultrasonic submarine cameras, submarine target classifiers, medical acoustic imaging and non-destructive tests.
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