摘要
本文基于功率MOSFET设计高频宽带线性功率放大器单片集成电路,主要针对功率放大器自身功耗和因高频下电路容性负载引起的信号相移及与此有关的功率放大器的效率问题.特别是选用高频功率MOSFET器件,通过电路优化设计使功放的转换速率达到最大,频带宽度达5-135 MHZ,在60 MHZ频率下,放大器的线性度为1 d B增益压缩点,在20-110 MHZ频率范围内,输入功率12 d B时,放大器的平均和最大增益分别为51.8 d B和53.5 d B,放大器的增益稳定性测试表明,频率60 MHZ,输入功率6 d B时,放大器的增益在24 d B-29 d B区间内波动.
To achieve a wide dynamic range,a power amplifier consisting of two stages is developed for ultrasound imaging applications through the implementation of custom-designed and the optimization of feedback circuits. The amplifier has broad bandwidth（ 5to 135 MHz）,maintaining a linearity up to the 1-d B gain compression point of 41. 5 d B,allowing 16 d B input power level at 60 MHz.The mean and the maximum values of output intercept points are 51. 8 and 53. 5 d B,respectively,between 20 and 110 MHz. With 12 d Bm input power,the gain of the amplifier varies between 24 and 29 d B,offering a uniformity which would allow excitation of a 70-MHz single- element transducer with windowed chirp-coded bursts sweeping from 40 to 100 MHz. The performance in high- frequency ultrasound imaging is evaluated with a wire phantom. Echo signal-to-noise ratio of the designed amplifier is 6 d B better than a commercial amplifier,and spatial resolution is maintained.
出处
《赣南师范学院学报》
2015年第6期35-38,共4页
Journal of Gannan Teachers' College(Social Science(2))
基金
国家自然科学基金项目(51377025)
