Thermoacoustic imaging(TAI)is an emerging high-resolution and high-contrast imaging technology.In recent years,metal wires have been used in TAI experiments to quantitatively evaluate the spatial resolution of differe...Thermoacoustic imaging(TAI)is an emerging high-resolution and high-contrast imaging technology.In recent years,metal wires have been used in TAI experiments to quantitatively evaluate the spatial resolution of different systems.However,there is still a lack of analysis of the response characteristics and principles of metal wires in TAI.Through theoretical and simulation analyses,this paper proposes that the response of metal(copper)wires during TAI is equivalent to the response of antennas.More critically,the response of the copper wire is equivalent to the response of a half-wave dipole antenna.When its length is close to half the wavelength of the incident electromagnetic wave,it obtains the best response.In simulation,when the microwave excitation frequencies are 1.3 GHz,3.0 GHz,and 5.3 GHz,and the lengths of copper wires are separately set to 11 cm,5 cm,and 2.5 cm,the maximum SAR distribution and energy coupling effciency are obtained.This result is connected with the best response of half-wave dipole antennas with lengths of 11 cm,4.77 cm,and 2.7 cm under the theoretical design,respectively.Regarding the further application,TAI can be used to conduct guided minimally invasive surgery on surgical instrument imaging.Thus,this paper indicated that results can also guide the design of metal surgical instruments utilized in different microwave frequencies.展开更多
对于金属载体上的线天线,采用RWG基函数以及伽略金法将电场积分方程转化为矩阵方程组,结合稳定双共轭梯度法,解算出表面电流的展开系数,进而得出金属载体上线天线的辐射特性。为了验证算法的正确性,以金属载体附近的单极子天线为例,采用...对于金属载体上的线天线,采用RWG基函数以及伽略金法将电场积分方程转化为矩阵方程组,结合稳定双共轭梯度法,解算出表面电流的展开系数,进而得出金属载体上线天线的辐射特性。为了验证算法的正确性,以金属载体附近的单极子天线为例,采用MOM(mehtod of moment)法以及软件FEKO进行仿真计算,两种方法的计算结果验证了算法的正确性。展开更多
基金supported by the National Natural Science Foundation of China(No.82071940).
文摘Thermoacoustic imaging(TAI)is an emerging high-resolution and high-contrast imaging technology.In recent years,metal wires have been used in TAI experiments to quantitatively evaluate the spatial resolution of different systems.However,there is still a lack of analysis of the response characteristics and principles of metal wires in TAI.Through theoretical and simulation analyses,this paper proposes that the response of metal(copper)wires during TAI is equivalent to the response of antennas.More critically,the response of the copper wire is equivalent to the response of a half-wave dipole antenna.When its length is close to half the wavelength of the incident electromagnetic wave,it obtains the best response.In simulation,when the microwave excitation frequencies are 1.3 GHz,3.0 GHz,and 5.3 GHz,and the lengths of copper wires are separately set to 11 cm,5 cm,and 2.5 cm,the maximum SAR distribution and energy coupling effciency are obtained.This result is connected with the best response of half-wave dipole antennas with lengths of 11 cm,4.77 cm,and 2.7 cm under the theoretical design,respectively.Regarding the further application,TAI can be used to conduct guided minimally invasive surgery on surgical instrument imaging.Thus,this paper indicated that results can also guide the design of metal surgical instruments utilized in different microwave frequencies.
文摘对于金属载体上的线天线,采用RWG基函数以及伽略金法将电场积分方程转化为矩阵方程组,结合稳定双共轭梯度法,解算出表面电流的展开系数,进而得出金属载体上线天线的辐射特性。为了验证算法的正确性,以金属载体附近的单极子天线为例,采用MOM(mehtod of moment)法以及软件FEKO进行仿真计算,两种方法的计算结果验证了算法的正确性。
