Multi-stage LNA with reduced mutual coupling

A method comprising:

• adjusting the gain of at least two variable gain amplifier stages;
• adjusting a resonant frequency and a quality factor (Q) of at least two tunable bandpass filters respectively connected as respective loads to the at least two variable gain amplifier stages, wherein each tunable bandpass filter of the at least two tunable bandpass filters includes a cross-coupled transistor pair, at least one cross-coupled compensation transistor pair, and a resonant tank, each resonant tank including an inductor, wherein each inductor of each resonant tank is oriented in orthogonal relation with respect to each respective longitudinal axis of each next inductor, the orthogonal relation of the respective longitudinal axes configured to reduce mutual coupling between the at least two tunable bandpass filters;
• and,
• biasing the respective at least one cross-coupled compensation transistor pair in a subthreshold region.

A method comprising:

• adjusting, to a first frequency, a resonant frequency of a first low noise amplifier stage having a first variable gain amplifier stage and a first tunable bandpass filter;
• adjusting, to a second frequency offset from the first frequency, a resonant frequency of a second low noise amplifier stage having a second variable gain amplifier stage and a second tunable bandpass filter;
• biasing cross-coupled compensation transistor pairs in each of the first tunable bandpass filter and second tunable bandpass filter in a sub-threshold region;
• and
• orienting the first and second tunable bandpass filters to reduce mutual coupling by providing a resonant tank within each of the first and second tunable bandpass filters with an inductor, wherein each inductor of each resonant tank is oriented in orthogonal relation with respect to each respective longitudinal axis of each next inductor, the orthogonal relation of the respective longitudinal axes configured to reduce mutual coupling between the first and second tunable bandpass filters.