The Design And Realization Of Transcranial Ultrasonic Stimulation System Based On FPGA And USB3.0

Neurological diseases are a serious threat to human health.In modern medicine,there is still a lack of effective means of diagnosis and treatment.Transcranial magnetic stimulation,transcranial electrical stimulation and other nerve stimulation and regulation techniques all have the disadvantages of insufficient depth of stimulation and low spatial resolution.Transcranial ultrasound stimulation has high resolution and can non-invasively stimulate specific brain functional areas.It has been widely studied by researchers.However,the current transcranial ultrasound stimulation system has some shortcomings such as less adjustable parameters and slower transmission speed.In order to overcome these defects,this paper designs and develops a multi-parameter adjustable and high-speed transcranial ultrasound stimulation system based on FPGA and USB3.0.First of all,for the transcranial ultrasonic stimulation system,the adjustable parameters are single and the transmission speed is slow.The whole hardware circuit framework of the transcranial ultrasound stimulation system is constructed.A transmit circuit with adjustable excitation pulse,a receiving hardware circuit with multiple sampling rates and programmable gain,and a high bandwidth communication control hardware circuit are designed.On this basis,the design principles and main functions of each module circuit are analyzed,and the hardware circuit and software interface of the transcranial ultrasound stimulation system are determined accordingly.Secondly,in order to realize the hardware circuit control and parameter adjustment of the transcranial ultrasound stimulation system,the software program for transcranial ultrasound stimulation system was programmed and the control parameters of each module were analyzed.Based on the system hardware circuit,FPGA software including digital filtering,DDR2 cache driver,USB3.0 high-speed transmission and communication protocol was developed.According to USB3.0 and FPGA communication interface,the firmware of USB internal FIFO read/write and serial communication were developed and then developed interactive software for imaging display and parameter adjustment.Finally,the transcranial ultrasound stimulation system was developed.Based on an independently designed hardware circuit schematic,a printed circuit board(PCB)was designed and produced.The excitation pulse and gain sampling parameters of the system were adjusted using interactive software,and the performance of the emitted ultrasound excitation of the system was tested using an oscilloscope,and the performance testing was performed on gain acceptance using interactive software.An experimental platform was set up to perform ultrasound brain stimulation experiments on mice.The EEG signal amplification system and the acquisition system were used to record mouse EEG signals,and the experimental process and experimental analysis were completed.