Analysis and design of a 1.8-2.7 GHz tunable 8-band TDD LTE receiver front-end

This paper describes the analysis and design of a 0.13μm CMOS tunable receiver front-end that supports 8 TDD LTE bands,covering the 1.8-2.7 GHz frequency band and supporting the 5/10/15/20 MHz bandwidth and QPSK/16QAM/64QAM modulation schemes.The novel zero-IF receiver core consists of a tunable narrowband variable gain low-noise amplifier(LNA),a current commutating passive down-conversion mixer with a 2nd order low pass trans-impedance amplifier,an LO divider,a rough gain step variable gain pre-amplifier,a tunable 4th order Chebyshev channel select active-RC low pass filter with cutoff frequency calibration circuit and a fine gain step variable gain amplifier.The LNA can be tuned by reconfiguring the output parallel LC tank to the responding frequency band,eliminating the fixed center frequency multiple LNA array for a multi-mode receiver. The large various gain range and bandwidth of the analog baseband can also be tuned by digital configuration to satisfy the specification requirement of various bandwidth and modulation schemes.The test chip is implemented in an SMIC 0.13μm 1P8M CMOS process.The full receiver achieves 4.6 dB NF,-14.5 dBm out of band IIP3, 30-94 dB gain range and consumes 54 mA with a 1.2 V power supply.     

应用于多模接收机的低功耗可编程增益放大器

针对多模接收机的应用,提出了引入一条闭环伪通路技术结构的可编程增益放大器,在保持一定的线性度及噪声性能的基础上,以较低的功耗实现较大的带宽.该电路增益步长为2 dB,增益变化范围1～39 dB.电路中内嵌了直流失调消除模块防止直流漂移引起的阻塞.芯片采用SMIC 0.13 μm 1P8M RF CMOS工艺实现.测试结...     

1.8～2.7GHz可调谐八波段时分LTE多模接收机前端的分析与设计

摘要：本文阐述了支持八波段可调谐时分LTE多模接收机前端的分析与设计,覆盖1.8～2.7GHz频率范围并支持5/10/15/20MHz三种带宽和QPSK/16QAM/64QAM 三种调制方式。零中频可调谐接收机前端的设计包括了可调谐窄带可变增益低噪声放大器,电流型下变频混频器和二阶低通输出跨阻放大器,可变增益预放大器,可调谐四阶切比雪夫低通信道选择滤波器和截止频率矫正电路,中频可变增益放大器。 窄带低噪声放大器可以在调谐范围内自由调节中心频率,从而替代了传统多模接收机中的低噪声放大器阵列,节省了芯片面积。模拟基带部分也可以通过数字接口调节增益和信道选择带宽。芯片在SMIC 0.13μm 1P8M CMOS上实现,测试结果显示双边带噪声系数达到4.6dB, 带外IIP3达到-14.5dBm,30～94dB增益范围。1.2V电源电压下芯片消耗功耗为54mA。