| The subject of this thesis is a comparison of two low noise amplifier (LNA) topologies for use in wireless local area networks (WLANs) operating in the 5–6GHz frequency range. A 1V transformer-feedback low noise amplifier, which has not been previously attempted in CMOS technology, is the primary focus of this work. The feedback design is benchmarked to a cascode LNA implemented in the same 0.18μm CMOS technology and operating from a 1.8V supply. Common performance specifications are targeted while attempting to minimize power consumption. The fully-differential transformer-feedback LNA achieves 14dB gain, 0.9dB noise figure, and +0.9dBm input IP3 while consuming 16mW. The differential cascode LNA realizes 14dB gain, 1.8dB noise figure, and +4.2dBm input IP3 while dissipating 21.6mW. These results demonstrate that the transformer-feedback LNA achieves competitive performance to the cascode topology while significantly reducing both the supply voltage and power dissipation. |
