Abstract: Systems and techniques for filtering of radiofrequency signals. A plurality of tunable cross-couple resonators are connected using capacitive coupling elements to form a cross-coupled bandpass filter. A center frequency of the filter may be set based on frequencies of the resonators and a fractional bandwidth of the filter may be set based on states of the capacitive coupling elements. Programmable zeroes of the filter may be set based on states of reactive elements coupling selected pairs of the resonators. The reactive elements may be capacitive, for zeroes below the center frequency, or inductive, for zeroes above the center frequency.

Abstract: Apparatus, method, and system example embodiments provide an improved RF front end to simultaneously transmit and receive signals for cellular telecommunications. In an example embodiment, an apparatus comprises a tunable duplexer selectively connected to an antenna, configured to transmit and receive radio frequency communication signals in a group of at least two bands; and a tunable transmit filter in the duplexer, capable of being tuned to have an inductance value approximately matching at least two inductance values corresponding respectively to pass the at least two bands in the group, each of the at least two bands in the group having a positive duplex offset and each of the at least two inductance values that correspond respectively to the at least two bands in the group, having an inductance value that approximately matches the inductance values corresponding respectively to the other bands in the group.

Abstract: Systems and techniques for filtering of radiofrequency signals. A plurality of tunable cross-couple resonators are connected using capacitive coupling elements to form a cross-coupled bandpass filter. A center frequency of the filter may be set based on frequencies of the resonators and a fractional bandwidth of the filter may be set based on states of the capacitive coupling elements. Programmable zeroes of the filter may be set based on states of reactive elements coupling selected pairs of the resonators. The reactive elements may be capacitive, for zeroes below the center frequency, or inductive, for zeroes above the center frequency.

Abstract: Apparatus, method, and system example embodiments provide an improved RF front end to simultaneously transmit and receive signals for cellular telecommunications. In an example embodiment, an apparatus comprises a tunable duplexer selectively connected to an antenna, configured to transmit and receive radio frequency communication signals in a group of at least two bands; and a tunable transmit filter in the duplexer, capable of being tuned to have an inductance value approximately matching at least two inductance values corresponding respectively to pass the at least two bands in the group, each of the at least two bands in the group having a positive duplex offset and each of the at least two inductance values that correspond respectively to the at least two bands in the group, having an inductance value that approximately matches the inductance values corresponding respectively to the other bands in the group.