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 mu and mu prime are well above 1 dB with IIP3 of about 15 dBm. The chip area is 0.57 x 0.57 mm(2) 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 mm(2). 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.