Multi-band tunable low noise amplifiers operating at 850MHz and 1900MHz standards

This paper presents two novel designs for narrowband tunable low-noise amplifier implementation operating at two frequency standards of 850 MHz and 1900 MHz (cellular frequencies such as GSM, CDMA and DCS standards). Both designs benefits from a simple cascode topology with tunable input and output matching networks. Two novel methods to tune the input resonating frequency are introduced: (1) switched transistor width technique, and (2) switched extra Miller and gate-source capacitances technique. Each technique shows its own pros and cons. A comparison between the post-layout simulations results of two designs is made while they are fully matched in desired frequencies. This paper also gives a comparison table between these designs and other similar works in terms of RF performance. The 0.13-μm RF CMOS tunable LNAs have a minimum and maximum power dissipations of 2 and 4 mW, respectively, depending on the tuned resonating frequency.