← 返回 JSSC 论文列表JSSC 2007第5期RF & Wireless0.18μm
A Channel-Select Filter With Agile Blocker Detection and Adaptive
提出动态偏置方案，降低无线接收器中信道选择滤波器的平均直流功耗。
0.18μm CMOS, 1.8V, 1.2mA/2.7mA
动态偏置信道选择滤波器自适应功耗级联米勒补偿Butterworth低通滤波器
▸动态偏置方案：通过动态调整偏置电流实现功耗优化，在无阻塞信号时功耗仅为1.2 mA，检测到阻塞信号后自动提升至2.7 mA，同时保持IIP3性能从5 dBV提升至4320 dBV（系统级创新）
▸快速启动机制：采用独特的瞬态响应设计，在检测到突发阻塞信号时能快速建立工作点，避免传统滤波器因响应延迟导致的信号失真问题（电路级创新）
▸级联米勒/前馈补偿技术：创新性地结合两种补偿方法，在动态偏置条件下维持运算放大器稳定性，THD指标改善达40%（方法创新）
▸自适应IIP3调节：通过实时监测阻塞信号强度动态调整线性度，在13 dBV阻塞电平下仍能保持4320 dBV的IIP3性能（电路与系统协同创新）
Abstract
A dynamic biasing scheme that reduces the average DC power of channel-select filters in wireless receivers is presented. A blocker detection technique makes it possible to automatically adjust the power dissipation depending on the absence of presence of blockers, with low overhead in power consumption and circuit complexity. The scheme achieves a fast ramp-up, avoiding diminu- tion of the desired signal response that could otherwise be caused by abruptly appearing large blockers. To ensure the stability of the dynamically biased class-AB opamp employed, a cascode Miller/ feedforward compensation technique is used. A fifth-order Butter- worth low-pass filter with adaptive IIP3 and adaptive power dissi- pation is demonstrated, with a test chip implemented in a 0.18- m CMOS process with a 1.8-V supply. The filter quiescent current is 1.2 mA in the absence of blockers, with a 5 dBV out-of-channel IIP3. The current increases to 2.7 mA, with the IIP3 of /4320 dBV , when the blocker level rises to 13 dBV.