Abstract: An amplifier structure may include a first amplifier substructure having a first amplifier and a first filter structure and provide a first high frequency output signal and a first low frequency output signal having a frequency lower than a frequency of the first high frequency output signal. It may include a second amplifier substructure having a second amplifier and a second filter structure and provide a second high frequency output signal and a second low frequency output signal having a frequency lower than the frequency of the second high frequency output signal. It may include a first combination node configured to receive the first high frequency output signal and the second low frequency output signal and to provide a first amplified signal, and a second combination node configured to receive the first low frequency output signal and the second high frequency output signal and to provide a second amplified signal.

Abstract: A filter includes a plurality of filtering paths. The plurality of filtering paths is driven by a corresponding plurality of local oscillator (LO) signals associated with an LO frequency. Each of the LO signals has a phase of a plurality of phases. Each filtering path of the plurality of filtering paths includes a plurality of signal generation branches. The plurality of signal generation branches is configured to receive a harmonic LO signal based on a fraction of the LO frequency, and generate an LO signal of the corresponding plurality of LO signals associated with the LO frequency using the harmonic LO signal.

Abstract: A tunable bandpass low-noise amplifier (LNA). The LNA includes a plurality of N-path filters and a plurality of cascode amplifiers. The cascode amplifiers are configured to amplify an input signal. Each N-path filter is coupled to a different one of the plurality of cascode amplifiers. The plurality of N-path filters are driven by local oscillator (LO) signals having different frequencies, and output nodes of the plurality of cascode amplifiers are coupled in parallel. The frequencies of the LO signals may be symmetrically spaced around a desired frequency (fLO). Each N-path filter may be coupled to a source of the common-gate device of the coupled cascode amplifier. The LO signals may be generated by a digital-to-time converter (DTC)-based frequency synthesizer. The frequencies of the LO signals supplied to the N-path filters may be adjusted to tune the bandwidth of the bandpass LNA.