Thermoacoustic imaging (TAI) is an emerging biomedical imaging method in which microwave is used as an excitation source to generate acoustic signals. The TAI possesses the advantages of high contrast of microwave imaging and high resolution of ultrasound imaging, which is also noninvasive. While the signal-to-noise ratio (SNR) of TAI is often very low. It is usually required by averaging the thermoacoustic signal many times to improve the SNR. However, averaging the signal to improve the SNR can significantly reduce the TAI’s time resolution, which hinders the development of rapid TAI. Here in this paper, we propose to reduce the cost and improve the time resolution of TAI based on multi-channel amplifier and additive circuit. The received thermoacoustic signals are divided into 4 channels and then entered into 4 amplifiers simultaneously.

After being amplified, the signals are added and collected by the data acquisition system for reconstructing the image. The phantom results indicate that the time resolution of TAI increases 5 times and the SNR rises from 6 dB to 12 dB, with the multi-channel amplifier and additive circuit adopted. The method proposed in this paper is helpful in promoting the development and clinical application of TAI, especially it has a great significance for developing the ultra-fast TAI.