A portable communication system is provided with modular components. The modular components can include internal modules located in a base unit and external modules that can be connected to predefined terminals on the exterior of the base unit. The internal modules can include modules that provide one or more of simplex, half-duplex or full-duplex communication modes. The external modules can include modules that can provide one or more of a full-duplex communication mode or a boost to the power level of the portable communication system. An internal connection can be connected to each of the terminals to provide internal couplings to the terminals. The internal modules can be connected to the external modules by the corresponding internal connections and terminals. The configuration of the portable communication system can be changed by disconnecting the internal modules and/or external modules from the base unit and then connecting new internal modules and/or external modules to the base unit.

A portable communication system is provided with modular components. The modular components can include internal modules located in a base unit and external modules that can be connected to predefined terminals on the exterior of the base unit. The internal modules can include modules that provide one or more of simplex, half-duplex or full-duplex communication modes. The external modules can include modules that can provide one or more of a full-duplex communication mode or a boost to the power level of the portable communication system. An internal connection can be connected to each of the terminals to provide internal couplings to the terminals. The internal modules can be connected to the external modules by the corresponding internal connections and terminals. The configuration of the portable communication system can be changed by disconnecting the internal modules and/or external modules from the base unit and then connecting new internal modules and/or external modules to the base unit.

A switchable RF transmit/receive (TX/RX) multiplexer, which includes a group of RF TX bandpass filters, a group of RF TX switching elements, and a group of RF RX bandpass filters; is disclosed. The group of RF TX bandpass filters includes a first RF TX bandpass filter and a second RF TX bandpass filter, such that each of the first RF TX bandpass filter and the second RF TX bandpass filter is coupled to a first filter connection node. The group of RF TX switching elements includes a first RF TX switching element coupled between the first filter connection node and a first common connection node, which is coupled to a first RF antenna. Each of the group of RF RX bandpass filters is coupled to the first common connection node.

A radio-frequency module includes duplexers and a phase circuit. A first transmitting-signal input terminal is connected to the duplexer, while a second transmitting-signal input terminal is connected to the duplexer. The phase circuit is connected between the first transmitting-signal input terminal and the duplexer. The phase circuit performs phase adjustment so that impedance matching between the first transmitting-signal input terminal and the duplexer is performed in the fundamental frequency band of a first transmitting signal, and so that the phase of the frequency band of a second transmitting signal in relation to the impedance characteristics of a first transmission path which ranges from the first transmitting-signal input terminal to the duplexer with the phase circuit provided therebetween appears in an open side on a Smith chart.

A switchable RF transmit/receive (TX/RX) multiplexer, which includes a group of RF TX bandpass filters, a group of RF TX switching elements, and a group of RF RX bandpass filters; is disclosed. The group of RF TX bandpass filters includes a first RF TX bandpass filter and a second RF TX bandpass filter, such that each of the first RF TX bandpass filter and the second RF TX bandpass filter is coupled to a first filter connection node. The group of RF TX switching elements includes a first RF TX switching element coupled between the first filter connection node and a first common connection node, which is coupled to a first RF antenna. Each of the group of RF RX bandpass filters is coupled to the first common connection node.

A portable communication system is provided with modular components. The modular components can include internal modules located in a base unit and external modules that can be connected to predefined terminals on the exterior of the base unit. The internal modules can include modules that provide one or more of simplex, half-duplex or full-duplex communication modes. The external modules can include modules that can provide one or more of a full-duplex communication mode or a boost to the power level of the portable communication system. An internal connection can be connected to each of the terminals to provide internal couplings to the terminals. The internal modules can be connected to the external modules by the corresponding internal connections and terminals. The configuration of the portable communication system can be changed by disconnecting the internal modules and/or external modules from the base unit and then connecting new internal modules and/or external modules to the base unit.

A resonator circuit, a filter with improved tunability, and a duplexer with improved tunability are disclosed. In an embodiment, the resonator circuit includes a resonator, a Z transformer and an impedance circuit, wherein the impedance circuit has an impedance Z and includes an impedance element, wherein the Z transformer is interconnected between the resonator and the impedance circuit, and wherein the Z transformer transforms the impedance Z to a new impedance ZZ and comprises a transformation circuit selected from: a generalized impedance converter (GIC), an negative impedance converter (NIC), a generalized impedance inverter (GII) and an negative impedance inverter (NII).

A stripline radial power combiner is provided. The stripline radial combiner comprises a first stripline level comprising N radial combiner arms coupled to a first common node; a second stripline level comprising a common port coupled to a second common node; wherein the first stripline level is mounted over the second stripline level; and wherein the first common node and the second common node are coupled by a conductive via through the first stripline level and the second stripline level.

A radio frequency (RF) receiver, for example a satellite positioning system receiver, can be configured to use a single phase locked loop for generating an oscillator signal to perform downconversion of signals in two different frequency bands using two or more local oscillators. A first RF signal portion includes a first signal band and undergoes double downconversion using a first mixer and a second mixer, while a second RF signal portion includes a second signal band and undergoes single downconversion using a single mixer. A controller is configured to determine a first oscillator divider value and a second oscillator divider value to avoid a jammer frequency and frequency dividers are used to generate the two or more local oscillators.

A high-frequency filter includes a first output to output a first signal, a first filter, a second filter, and a first matching circuit connected to an output of the first filter and to an output of the second filter. The first signal is provided to the first output from one of the output of the first filter and the output of the second filter via the first matching circuit. The first matching circuit includes a resonator connected in series between the first output and the output of only one of the first filter and the second filter.