A novel digitally controlled automatic gain control （AGC） loop circuitry for the global navigation satel- lite system （GNSS） receiver chip is presented. The entire AGC loop contains a programmable gain amplifier ...A novel digitally controlled automatic gain control （AGC） loop circuitry for the global navigation satel- lite system （GNSS） receiver chip is presented. The entire AGC loop contains a programmable gain amplifier （PGA）, an AGC circuit and an analog-to-digital converter （ADC）, which is implemented in a 0.18 μm complementary metal--oxide-semiconductor （CMOS） process and measured. A binary-weighted approach is proposed in the PGA to achieve wide dB-linear gain control with small gain error. With binary-weighted cascaded amplifiers for coarse gain control, and parallel binary-weighted trans-conductance amplifier array for fine gain control, the PGA can provide a 64 dB dynamic range from -4 to 60 dB in 1.14 dB gain steps with a less than 0.15 dB gain error. Based on the Gaussian noise statistic characteristic of the GNSS signal, a digital AGC circuit is also proposed with low area and fast settling. The feed-backward AGC loop occupies an area of 0.27 mm^2 and settles within less than 165 μs while consuming an average current of 1.92 mA at 1.8 V.展开更多
针对传统自动增益控制（automatic gain control,AGC）环路的调节时间随输入信号幅度减小而增长的缺点,改进传统AGC环路并进行对数域分析,推导其时间常数,提出一种固定时间常数、易于数字化硬件实现的方法,进行了AGC环路的Matlab仿真和...针对传统自动增益控制（automatic gain control,AGC）环路的调节时间随输入信号幅度减小而增长的缺点,改进传统AGC环路并进行对数域分析,推导其时间常数,提出一种固定时间常数、易于数字化硬件实现的方法,进行了AGC环路的Matlab仿真和包络检波、对数运算以及环路滤波模块的现场可编程门阵列（field programmable gate array,FPGA）实现。仿真和实现结果均表明：改进AGC的调节时间不受输入信号幅度的影响,能显著提高无线通信系统的频带利用率。展开更多
设计了一款应用于移动数字电视调谐器芯片中的数字式内环自动增益控制(Automatic Gain Control,AGC)电路。该控制电路采用的算法有效避免了死循环的问题,并且提高了AGC电路的响应时间。电路设计利用Verilog硬件描述语言进行描述,通过了...设计了一款应用于移动数字电视调谐器芯片中的数字式内环自动增益控制(Automatic Gain Control,AGC)电路。该控制电路采用的算法有效避免了死循环的问题,并且提高了AGC电路的响应时间。电路设计利用Verilog硬件描述语言进行描述,通过了功能仿真并在FPGA上进行了验证。最终采用TSMC 0.13μm CMOS工艺,完成了电路版图。芯片面积在126μm×106μm,平均功耗在3.876 mW左右。展开更多
自动增益控制(Automatic Gain Control,AGC)电路是接收机的重要组成部分,其作用是改善接收机的动态范围。采用反馈型自动增益控制结构,通过控制可变增益放大器AD603和电子开关,设计一个大动态范围快速闭环的AGC电路。实测结果表明,其动...自动增益控制(Automatic Gain Control,AGC)电路是接收机的重要组成部分,其作用是改善接收机的动态范围。采用反馈型自动增益控制结构,通过控制可变增益放大器AD603和电子开关,设计一个大动态范围快速闭环的AGC电路。实测结果表明,其动态增益控制范围为-10~+70 dB,闭环时间为30μs,能够广泛应用于各种定频、跳频通信,保证接收机正常工作。展开更多
文摘A novel digitally controlled automatic gain control （AGC） loop circuitry for the global navigation satel- lite system （GNSS） receiver chip is presented. The entire AGC loop contains a programmable gain amplifier （PGA）, an AGC circuit and an analog-to-digital converter （ADC）, which is implemented in a 0.18 μm complementary metal--oxide-semiconductor （CMOS） process and measured. A binary-weighted approach is proposed in the PGA to achieve wide dB-linear gain control with small gain error. With binary-weighted cascaded amplifiers for coarse gain control, and parallel binary-weighted trans-conductance amplifier array for fine gain control, the PGA can provide a 64 dB dynamic range from -4 to 60 dB in 1.14 dB gain steps with a less than 0.15 dB gain error. Based on the Gaussian noise statistic characteristic of the GNSS signal, a digital AGC circuit is also proposed with low area and fast settling. The feed-backward AGC loop occupies an area of 0.27 mm^2 and settles within less than 165 μs while consuming an average current of 1.92 mA at 1.8 V.
文摘自动增益控制(Automatic Gain Control,AGC)电路是接收机的重要组成部分,其作用是改善接收机的动态范围。采用反馈型自动增益控制结构,通过控制可变增益放大器AD603和电子开关,设计一个大动态范围快速闭环的AGC电路。实测结果表明,其动态增益控制范围为-10~+70 dB,闭环时间为30μs,能够广泛应用于各种定频、跳频通信,保证接收机正常工作。
