Research And Design Of The Wireless Receiver In The Multi-mode Differential Low Noise Amplifier

With the development of wireless communications technologies, the new communication standards appeared in recent years. As an opening wireless receiver platform, reconfigurable multi-standard or multi-mode receivers are proposed to meet different standards or protocols applification.The low noise amplifier is one of the most important modules in RF front-end of a wireless communication transceiver. As the first stage of wireless receiver, the major function of low noise amplifier is to magnify the weak desired signal without deteriorating signal noise ratio, and to deliver the RF signal to the next stage filter or mixer.A multi-mode differential low noise amplifier under ESD protection for the wireless receiver is presented. The structure and the spec of multi-mode low noise amplifier are analyzed and the circuit is verified.Firstly, two dominant receiver architectures in wireless communication system are introduced:low IF architecture and direct-conversion (zero IF) architecture. The configurations of two dominant receiver architectures are analyzed. The advantage and disadvantage are compared between two dominant receiver architectures, and the design considerations are illuminated. The spec of multi-mode low noise amplifier is proposed thereof.Secondly, several electrostatic discharge (ESD) protection circuits are introduced considering the reliability of high-speed integrated circuits in deep sub-micron CMOS process.The Grounded-Gate NMOS is analyzed and implemented in the LNA design in order to lower parasitic capacitance and enhance ESD robustness.Thirdly, basis on above analysis, a multi-mode differential narrow-band low noise amplifier for DCS1800, PCS1900, WCDMA and Bluetooth application is designed. It employs inductively degenerated common-source common-gate low noise amplifier, and can work at different wireless conmmunication standards. By changing off-chip input matching network and adjusting switched-capacitors of output LC resonant network, it achieves different resonant frequencies. With the consideration of parasitic capacitor of ESD protection PAD and package, the input matching network, voltage gain, noise figure and linearity are analyzed, the input matching network and noise figure are optimized as well.Further, the differential input and output matching network are analyzed in detail with consideration of off-chip Balun. The impact of package and bonding for the measurement is illuminated.Finally, the chip measurement results are presented, and measurement results show that noise figure of 2.3,2.3,2.4,2.5dB; power gain of 8.0,8.8,9.3dB,dB; IIP3 of -9.0,-6.3,-2.6,-1.5 dBm in DCS1800,PCS1900,WCDMA,Bluetooth, respectively, while dissipating 3.3 mA from a 1.2 V supply. The theory analysis and circuit design consideration of multi-mode low noise amplifier are verified through measurement. The low noise amplifier achievers good performance in every frequency band, and can meet the requirement of wireless receiver systems.