Abstract: There are first and second antennas proximally disposed and configured to resonate within respective first and second frequency bands, which may overlap. An impedance stabilization circuitry is coupled to ground. There is a selective coupler (for example, diplexer, directional coupler, switch) interfacing the second antenna selectively with the impedance stabilization circuitry and with radio circuitry. The selective coupler comprises a first port coupled to the second antenna, a second port coupled to the impedance stabilization circuitry, and a third port configured to couple with radio circuitry that is configured to operate in the second frequency band. The selective coupler provides a predetermined impedance to signals within the first frequency band and a low insertion loss to signals within the second frequency band, thus providing a stable impedance for the first antenna's view of the second antenna.

Abstract: An apparatus includes a tunable diplexer; first, second and third radio nodes; and path selection circuitry. The tunable diplexer includes a dedicated port, at least a first signal port and a second signal port, and control inputs configured to change at least one of frequency characteristics and phase characteristics of the tunable diplexer. The path selection circuitry is configurable to select between a first signal pathway between the third radio node and the first signal port and a second signal pathway between the third radio node and the second signal port. The tunable diplexer may have control signals inputs to select between the first and second signal pathways based on an expected interference scenario between radio signals at the first and second signal ports, and the control signals may change frequency characteristics and/or phase characteristics of at least one of the signal ports based on an operational condition of the apparatus.

Abstract: Described is a filtering arrangement in which a first filter is configured to exhibit a first frequency response FR and has a first node and a second node; a second filter is configured to exhibit a second FR and has a first node and a second node; and a third filter is configured to exhibit a third FR and has a first node and a second node. A first common node interfaces the second node of the first filter with the second node of the second filter; and a second common node interfaces the first node of the second filter with the first node of the third filter. The second FR exhibited by the second filter isolates a first signal on a first signal path between the first node of the first filter and the first common node from a second signal on a second signal path between the second common node and the second node of the third filter.

Abstract: A radio use case is determined for concurrently operating radios of a multi-radio device and/or transmitter and receiver of a FDD radio. A local memory is accessed with the determined use case to find a high and/or a low frequency cutoff for the concurrent operation radio or transmitter/receiver. Control signals are applied to impose the high and/or the low frequency cutoff to a pair of frequency adjustable diplexers that are in series with one another in one of a transmit branch or a receive branch of a duplexer circuit that is disposed between the radio and an antenna. Then, a receive signal is passed through the antenna and the receive branch of the duplexer circuit to the radio or receiver of the FDD radio, or a transmit signal is passed from the respective radio or transmitter of the FDD radio through the transmit branch of the duplexer circuit to the antenna.

Abstract: There are first and second antennas proximally disposed and configured to resonate within respective first and second frequency bands, which may overlap. An impedance stabilization circuitry is coupled to ground. There is a selective coupler (for example, diplexer, directional coupler, switch) interfacing the second antenna selectively with the impedance stabilization circuitry and with radio circuitry. The selective coupler comprises a first port coupled to the second antenna, a second port coupled to the impedance stabilization circuitry, and a third port configured to couple with radio circuitry that is configured to operate in the second frequency band. The selective coupler provides a predetermined impedance to signals within the first frequency band and a low insertion loss to signals within the second frequency band, thus providing a stable impedance for the first antenna's view of the second antenna.

Abstract: Described is a filtering arrangement in which a first filter is configured to exhibit a first frequency response FR and has a first node and a second node; a second filter is configured to exhibit a second FR and has a first node and a second node; and a third filter is configured to exhibit a third FR and has a first node and a second node. A first common node interfaces the second node of the first filter with the second node of the second filter; and a second common node interfaces the first node of the second filter with the first node of the third filter. The second FR exhibited by the second filter isolates a first signal on a first signal path between the first node of the first filter and the first common node from a second signal on a second signal path between the second common node and the second node of the third filter.

Abstract: A radio use case is determined for concurrently operating radios of a multi-radio device and/or transmitter and receiver of a FDD radio. A local memory is accessed with the determined use case to find a high and/or a low frequency cutoff for the concurrent operation radio or transmitter/receiver. Control signals are applied to impose the high and/or the low frequency cutoff to a pair of frequency adjustable diplexers that are in series with one another in one of a transmit branch or a receive branch of a duplexer circuit that is disposed between the radio and an antenna. Then, a receive signal is passed through the antenna and the receive branch of the duplexer circuit to the radio or receiver of the FDD radio, or a transmit signal is passed from the respective radio or transmitter of the FDD radio through the transmit branch of the duplexer circuit to the antenna.

Abstract: An apparatus includes a tunable diplexer; first, second and third radio nodes; and path selection circuitry. The tunable diplexer includes a dedicated port, at least a first signal port and a second signal port, and control inputs configured to change at least one of frequency characteristics and phase characteristics of the tunable diplexer. The path selection circuitry is configurable to select between a first signal pathway between the third radio node and the first signal port and a second signal pathway between the third radio node and the second signal port. The tunable diplexer may have control signals inputs to select between the first and second signal pathways based on an expected interference scenario between radio signals at the first and second signal ports, and the control signals may change frequency characteristics and/or phase characteristics of at least one of the signal ports based on an operational condition of the apparatus.

Abstract: A circuit includes a radiofrequency circuit component, a diplexer, a termination, and a further component. The diplexer includes a common port configured to receive an input from the radiofrequency circuit component, a first output port, and a second output port. The termination is configured to receive an input from the first output port of the diplexer. The further component is configured to receive a radiofrequency signal input from the second output port of the diplexer. The circuit may be adapted for a multi-radio device and have a control input for varying a frequency split between the first and second output port according to a radio use case of radios in simultaneous operation.