Active feedback supported CMOS LNA blended with coplanar waveguide‐fed antenna for Wi‐Fi networks

Abstract

This study presents integration of complementary CMOS active feedback low noise amplifier with coplanar waveguide fed patch antenna for Wi-Fi networks. The LNA design-I, involves a cascode amplifier followed by active feedback common source amplifier offering wideband impedance matching with lowered parasitic losses. The inductor-less feedback mechanism is used to nullify noise effect with extended bandwidth in the range of 2.2 to 5.8 GHz and a peak forward gain of 22.5 dB. It is implemented on agilent's advance design system using 45 nm CMOS process. The noise figure (NF) is approximately 2 dB while the stability factors µ and µ prime are well above 1 dB with IIP3 of about 15 dBm. The chip area is 0.57 x 0.57 mm2 under dc power supply of 1V while power consumption of 0.8 mW. A CPW fed antenna design-II, achieves a wide band response similar to the bandwidth of LNA. The size of the fabricated antenna is calculated as 40 x 40 mm2. The peak gain is approximately 4.1 dBi at 3.9 GHz. The codesign-III, proposes a receiver achieving a much wider band of 1.6 to 6 GHz with a gain of 16.5 dB and NF of 2.59 dB at 2.06 GHz. The codesign improves the system integration by reducing overall chip area and offers saving in the effective cost.