Abstract: The present disclosure teaches a filtering device. The filtering device comprises a transforming unit, at least a first filtering element and a complementary filtering unit. The filtering device of the present disclosure allows an isolation of radio signals within a selected frequency band. Frequency bands closely-spaced to the selected frequency band may be suppressed. The present disclosure provides a reliable and almost identical response to temperature changes for the pass band within the selected frequency band and the stop bands closely-spaced to the selected frequency band. The filtering device withstands temperature changes without affecting a filtering performance different to the prior art. The present disclosure further provides a method for filtering an input signal as well as a computer program product for the manufacture of the filtering device and a computer program product for the carrying out of the method of filtering.

Abstract: The present invention relates to a method and system for high-speed bandpass serial data communication. A driver receives at least one data signal and generates a bandpass data signal for transmission through a bandpass waveguide interconnect. The bandpass data signal is launched into the bandpass waveguide interconnect using a first adaptor and extracted therefrom after transmission using a second adaptor. A receiver connected to the second adaptor recovers the at least one data signal from the extracted bandpass data signal. A dispersion compensation circuit receives one of the at least one data signal and the bandpass data signal and information indicative of a phase response of the bandpass waveguide interconnect and dispersion compensates the one of the at least one data signal and the bandpass data signal by compensating the phase response of the bandpass waveguide interconnect.

Abstract: In a duplexer module, a transmitting signal is correctly monitored without deteriorating receiving sensitivity. The duplexer module includes a transmission line, a reception line, and an antenna common line, and performs conversion between a transmission signal and a reception signals and antenna common signals. A transmission filter is inserted into the transmission line, and the transmission filter allows the transmission signal to pass therethrough and stops the reception signal. A reception filter is inserted into the reception line, and the reception filter allows the reception signal to pass therethrough and stops the transmission signal. A first line of a coupler which detects the transmitting signal is inserted into the transmission line at a stage subsequent to the transmission filter.

Abstract: A demultiplexer has a common terminal, a transmission terminal, and a reception terminal, and furthermore includes a transmission filter connected between the common terminal and the transmission terminal, a reception filter connected between the common terminal and the reception terminal, and a phase shift circuit connected in series to the reception filter connected between the common terminal and the reception terminal. A node on the line from the phase shift circuit to the common terminal or the transmission terminal, and a node on the line from the phase shift circuit to the reception terminal are coupled via a reactance. Accordingly, it is possible to fundamentally reduce or eliminate the situation in which transmission signals from the transmission filter arrive at the reception circuit, and improve isolation.

Abstract: A duplexer module that is used for transmission and reception of a signal in at least two communication systems using different frequency bands includes a wiring board, dual transmission filters in a transmission filter unit that is provided on the wiring board and that includes a transmission filter, and dual reception filters in a reception filter unit that is provided on the wiring board and that includes a reception filter. Each of the dual reception filters includes at least two reception filters having different frequency bands, and the output side of the reception filters is shared between the reception filters such that a common output terminal is provided for the reception filters.

Abstract: Distributed band reject filters are disclosed. A band reject filter includes a first acoustic resonator and a second acoustic resonator, each of which has either shunt resonators adapted to resonate substantially at respective resonance frequencies defining a rejection frequency band or series resonators adapted to anti-resonate substantially at respective anti-resonance frequencies defining the rejection frequency band. These resonators are connected through a phase shifter which imparts an impedance phase shift of approximately 45° to 135°. Exemplary applications of the band reject filters disclosed herein include implementation as an inter-stage band reject filter for a base station power amplifier for a wireless communication system, as a radio frequency band reject filter in a duplexer for a wireless communication terminal, and in a low noise amplifier input stage.

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: There is provided a radio communication apparatus for transmitting transmission signals of the channel CH1 and the channel CH2, including a first antenna, a second antenna, a dual-band transmitting/receiving circuit having a first terminal for the channel CH1 and a second terminal for the channel CH2, a first branching circuit configured to receive a transmission signal from the first terminal or the second terminal, a second branching circuit configured to divide the transmission signal from the first branching circuit between the first antenna and the second antenna, and a transmission line configured to connect the first branching circuit and the second branching circuit.

Abstract: A diplexer circuit comprising a common terminal, a low-frequency-side terminal, a high-frequency-side terminal, a low-frequency-side path comprising a low-frequency filter disposed between the common terminal and the low-frequency-side terminal, and a high-frequency-side path comprising a high-frequency filter disposed between the common terminal and the high-frequency-side terminal, the low-frequency filter comprising a first transmission line series-connected to the low-frequency-side path and a capacitor parallel-connected to part of the first transmission line.

Abstract: A duplexer includes a transmit filter connected between a common terminal and a transmission terminal, a receive filter connected between the common terminal and a reception terminal, a capacitor connected in parallel with one of the transmit filter and the receive filter and provided between two terminals of the common terminal, the transmission terminal, and the reception terminal, and a package. The package includes an insulating layer, foot pads that include the common terminal, the transmission terminal and the reception terminal and are formed on one surface of the insulating layer, and interconnections formed on another surface opposite to the one surface of the insulating layer. The capacitor is composed of two capacitor forming units that are connected in parallel with each other and are formed with at least one foot pad of the foot pads and two of the interconnections that overlap with two opposing sides of the at least one food pad respectively.

Abstract: A filter includes: a converter circuit, provided with a single-type common terminal and two balanced terminals, for performing conversion between a balanced line and an unbalanced line; two filter units coupled to each of the balanced terminals of the converter circuit and allowing passage of a signal in a pass band; and a bridging capacitor arranged to extend across the converter circuit and one of the filter units in a bridging manner, wherein the inductance of an opposite-side line of one of the filter units relative to the converter circuit is electromagnetically coupled to the inductance of a line coupling the other filter unit and the converter circuit.

Abstract: The present invention relates to a lumped cross-coupled Wilkinson circuit having a pair of magnetically cross-coupled inductive elements coupled to an isolation network. By magnetically cross-coupling the inductive elements, which have a mutual inductance, the inductance of each inductive element will be significantly less than the inductance of each inductive element in an equivalent lumped traditional Wilkinson combiner. Since the inductance of each inductive element is less, the size of each inductive element may be significantly smaller and the resistive loss of the each inductive element may be significantly smaller. In one embodiment of the present invention, the lumped cross-coupled Wilkinson circuit operates as a lumped cross-coupled Wilkinson combiner. In an alternate embodiment of the present invention, the lumped cross-coupled Wilkinson circuit operates as a lumped cross-coupled Wilkinson splitter.

Abstract: An impedance matching apparatus is provided. The impedance matching apparatus includes a signal separation unit, an impedance detection unit, and an impedance matching unit. The signal separation unit separates a transmission and reception signal, and selectively passes a desired frequency corresponding to the transmission and reception signal. The impedance detection unit includes a plurality of impedances, and detects first and second electric potentials between the impedances. The impedance matching unit compares the first and second electric potentials detected by the impedance detection unit, and changes a matching factor for one of the impedances included in the impedance detection unit to match the impedances according to the compared result.

Abstract: A technique for realizing module size reduction while enhancing the anti-ESD characteristic of a low frequency band circuit without the need to add such an element as an ESD filter. In a diplexer included in a high-frequency power amplifier module, a composite grounding inductor with respect to an antenna terminal is formed of three inductors including a series inductor contained in a lowpass filter. Since an ESD signal contains main components thereof belonging to a frequency band of the order of a few hundreds of MHz or lower, the ESD signal is allowed to pass through a lowpass filter with little to no attenuation. Under this condition, a function for ESD filtering from the antenna terminal to an antenna switch circuit is provided by using the composite grounding inductor mentioned above and an electrostatic capacitor element, thereby suppressing passage of the ESD signal to the antenna switch circuit.

Abstract: A multiband circuit includes a signal path comprising a first signal branch that includes a first circuit that is transmissive in a first frequency band and a second signal branch that includes a second circuit that is transmissive in a second frequency band. The first and second signal branches are combined on an antenna side into a common path.

Abstract: A high-frequency module includes a balanced demultiplexer including a pair of balanced signal terminals and that has at least one of high differential isolation and high differential attenuation. A distance between an antenna terminal and a second balanced signal terminal provided on a mounting surface of a circuit board is greater than the antenna terminal and a first balanced signal terminal. On a back surface of the circuit board, a distance between a first back surface side electrode pad to which the antenna terminal is connected and a fourth back surface side electrode pad to which the second balanced signal terminal is connected is less than a distance between the first back surface side electrode pad to which the antenna terminal is connected and a third back surface side electrode pad to which the first balanced signal terminal is connected.

Abstract: A duplexer of the present invention includes a reception filter (3) for passing signals in a predetermined frequency band and attenuates signals in the other frequency bands among reception signals input to an antenna port, and a transmission filter (4) for passing signals in a predetermined frequency band and attenuates signals in the other frequency bands among transmission signals input from the outside and outputting them to the antenna port. The duplexer further includes a conversion circuit (22) provided with a single-ended input terminal connected to the antenna port and balanced output terminals. The reception filter (3) is provided with a balanced input terminal connected to the output terminal of the conversion circuit (22) and a balanced output terminal for outputting the filtered reception signal.

Abstract: A duplexer includes a common terminal, receiving filters, a transmitting filter, and a hybrid having four terminals (terminals 1 to 4). A first terminal (terminal 1), which is one of the four terminals of the hybrid is connected to the common terminal, the receiving filters are connected to a second terminal and a third terminal to which a signal is transmitted if it is input from the first terminal, and a transmitting filter is connected to a fourth terminal (terminal 4) of the hybrid. Thus, it is possible to improve the isolation of the duplexer, while avoiding an increase in the number of parts as well as greater complexity.

Abstract: A system includes a plurality of band pass filters to pass signals in separated frequency bands to or from an antenna. A matching network provides characteristic impedances. The system is designed such that the configuration of the matching network and BPFs provides high impedance to the band pass filters for those routing paths other than the band pass path as these routing paths do not transmit or receive the signals at this particular pass band. The system is further designed such that the configuration of the matching network and BPFs provides minimal insertion loss for the band pass path of for transmission and receipt of signals at this particular pass band, where each routing path has a corresponding pass band. The matching network is for coupling to an amplifier, when frequency separation is needed at the output of the amplifier to the BPFs. In one embodiment an impedance network tunes the impedance by using varying length transmission lines.

Abstract: The invention relates generally to RF and microwave multiplexers implemented with a plurality of coupled resonators. More specifically, the present invention relates to multiplexers configured to require only a plurality of resonators and series, shunt, cross couplings and input/output couplings between them. It is a main feature of the invention that no microwave dividers, combiners, circulators, or other junctions are necessary for the distribution of microwave energy among the coupled resonators. This is achieved for example by a P-channel multiplexer comprising P rows of coupled resonators, a common input terminal connected to the first resonator of at least one of said rows, and P channel output terminals connected with the last resonator in each row, and at least one coupling between resonators belonging to different rows.

Abstract: A multi-band high-frequency circuit for performing wireless communications among pluralities of communication systems having different communication frequencies. A high-frequency switch circuit contains: switching elements for switching the connection of pluralities of multi-band antennas to transmitting circuits and receiving circuits; a first diplexer circuit disposed between the high-frequency switch circuit and transmitting circuits for branching a high-frequency signal into frequency bands of the communication systems; and a second diplexer circuit disposed between the high-frequency switch circuit and receiving circuits for branching a high-frequency signal into frequency bands of the communication systems.

Abstract: According to one exemplary embodiment, a three-way splitter includes a printed element and a resistive network comprising discrete resistors. A first printed branch, second printed branch, and third printed branch distribute a received communication signal to respective outputs having substantially the same phase, frequency, and impedance. Each printed branch includes a number of substantially ninety-degree angles. In one embodiment, the printed branches are quarter wavelength transmission lines in a frequency range of 1.5 GHz. In one embodiment, the three-way splitter consumes less than one square inch of surface area on a printed circuit board, and can be used in a satellite receiving system, for example. In this embodiment, the three-way splitter is utilized for frequencies in the range of approximately 900 MHz to 2.2 GHz.

Abstract: Circuitry, architectures, devices and systems for multi-band radio communications using a balanced-unbalanced duplexer. An integrated balanced-unbalanced duplexer for multi-band communications may include an unbalanced multi-band port; a first balanced single-band port; a second balanced single-band port; a first unbalanced coupling arm conductively coupled to the unbalanced multi-band port; a second unbalanced coupling arm conductively coupled to the unbalanced multi-band port; a first pair of balanced coupling arms conductively coupled to the first balanced single-band port and electromagnetically coupled to the first unbalanced coupling arm; and a second pair of balanced coupling arms conductively coupled to the second balanced single-band port and electromagnetically coupled to the second unbalanced coupling arm. The architectures and/or systems generally include components embodying one or more of the concepts disclosed herein.

Abstract: A signal splitter comprising an input and a plurality of outputs is provided, wherein alternate outputs are connected to phase shifting devices. The phase shifting devices preferably comprise phase shifting transformers and introduce a phase shift of 180°, so that noise components of alternate outputs are antiphase and cancel one another out almost entirely when the signals are summed. Also provided is a cable television network comprising a plurality of such signal splitters to ensure that noise ingress in upstream signals passing into the network is substantially reduced.

Abstract: A filter package is provided with a support structure, a filter device having terminals, impedance matching circuits formed on the support structure and electrically connected to at least some of the terminals of the filter device, and at least one electrical ground structure electrically connected to the impedance matching circuits. Moreover, the filter package has an outer housing to contain the support structure, filter device, impedance matching circuits, and at least one ground structure.

Abstract: A duplexer includes a transmit filter of a ladder type filter, connected between a common terminal and a transmitting terminal, and a receive filter of the ladder type filter, connected between the common terminal and a receiving terminal. One or more parallel resonators in the transmit filter are grounded through a transmitting inductance, and a portion of multiple parallel resonators are grounded through a first receiving inductance and a remaining portion of the multiple parallel resonators are grounded through a second receiving inductance.

Abstract: A multi-band high-frequency circuit for performing wireless communications among pluralities of communication systems having different communication frequencies, comprising a high-frequency switch circuit comprising switching elements for switching the connection of pluralities of multi-band antennas to transmitting circuits and receiving circuits; a first diplexer circuit disposed between the high-frequency switch circuit and transmitting circuits for branching a high-frequency signal into frequency bands of the communication systems; a second diplexer circuit disposed between the high-frequency switch circuit and receiving circuits for branching a high-frequency signal into frequency bands of the communication systems; the first and second diplexer circuits each comprising a lower-frequency filter circuit and a higher-frequency filter circuit, a bandpass filter circuit being used as the lower-frequency filter circuit in the second diplexer circuit, or disposed between the lower-frequency filter circuit in t

Abstract: A diplexer provides a high degree of design freedom for satisfying the requirements of electric characteristics so as to realize desired characteristics and at the same time can be downsized and a multiplexer is realized by using such a diplexer. The diplexer includes a filter having a first pass band and a filter having a second pass band with a frequency band at least twice as high as the frequency band of the first pass band, the filter having the first pass band being a filter of the lumped constant type, the filter having the second pass band being a filter of the distributed constant type.

Abstract: Tunable impedance matching networks and tunable diplexer matching systems are provided. A tunable impedance matching network can include an impedance element connected between first and second nodes for communicating signals between the first and second nodes. For example, the impedance element can be a transmission line or an inductor. Further, the matching network can include a first capacitor connected in parallel with the impedance element, wherein the first capacitor is tunable. The matching network can also include a second capacitor comprising first and second terminals. The first terminal of the second capacitor can be connected to the first node. The second terminal of the second capacitor can be connected to a local voltage reference for the first node. A third capacitor comprises first and second terminals. The first terminal of the second capacitor can be connected to the second node. The second and third capacitors can also be tunable.

Abstract: A high-integrated duplexer and a fabrication method thereof. The duplexer has a first filter to pass a signal of a transmitted frequency band, a second filter to pass a signal of a received frequency band, an embedded PCB having the first and second filters bonded on a certain area of a surface of an upper side in a predetermined distance from each other, and an isolation part to prevent a signal interference between the first and second filters, and a packaging substrate to package the entire upper side of the embedded PCB so that the packaging substrate is located above and separated from the first and second filters by a predetermined distance. The fabricated high-integrated duplexer has a small size and high performance.

Abstract: A circuit and antenna arrangement includes a diplexer having a single radio frequency input/output interface and dual feed connections with an antenna adapted for use over a plurality of frequency bands. The diplexer has a capacitance connected between the radio frequency input/output interface and the antenna, and further has an additional capacitance that is selectively one of connected or not connected in parallel with the capacitance. In one embodiment the additional capacitance may be a capacitor in series with a switch, while in another embodiment the additional capacitance may be a MEMS variable capacitor.

Abstract: A multiplexer circuit for CB, AM/FM, and television splits the radio and television signals, adding impedance to the split lines, and providing an amplifier upstream of the split.

Abstract: A balanced-output triplexer includes: a first filter provided between an input terminal and a pair of first balanced output terminals; a second filter provided between the input terminal and a pair of second balanced output terminals; and a third filter provided between the input terminal and a pair of third balanced output terminals. Each of the first to third filters has a pair of output resonators that are interdigital-coupled to each other and connected to the corresponding pair of balanced output terminals.

Abstract: A diplexer for receiving and transmitting a first bandwidth signal corresponding to a first central frequency and a second bandwidth signal corresponding to a second central frequency includes a first signal end, a second signal end, a third signal end, a first impedance unit, a second impedance unit and a third impedance unit. The first impedance unit forms an impedance match with the third impedance unit when the third signal end receives or transmits the first bandwidth signal, and forms a high impedance unit when the third signal end receives or transmits the second bandwidth signal. The second impedance unit forms an impedance match with the third impedance unit when the third signal end receives or transmits the second bandwidth signal, and forms a high impedance unit when the third signal end receives or transmits the first bandwidth signal.

Abstract: A manifold combiner for a plurality of radio frequency electromagnetic signals includes a first RF bandpass filter element with input and output ports and a first junction element, wherein the first junction element includes a first port connected to the first filter output port, a second port connected to a shorted stub element, and a third port functioning as an output. The signal path toward the stub appears as an open to the first filter. The combiner further includes at least one additional filter element and junction element, with the second port of the additional junction element fed from the output of the previous junction element. Interconnecting sections couple the respective elements. Dimensions of interconnecting sections are selected such that each filter element output sees a single path out of the manifold, through the output of the last junction element, with all other possible paths appearing as open circuits.

Abstract: A terminal is provided for selectively communicating in at least two frequency bands. The terminal includes an antenna transducer including a first port and a second port, where the antenna transducer is capable of selectively transducing first radio signals (e.g., low power radio frequency (LPRF) signals) to and/or from the first port, and/or second radio signals (e.g., global positioning system (GPS) signals) to and/or from the second port. In this regard, the antenna transducer is capable of transducing first radio signals such that an impedance at the second port approaches a short circuit or an open circuit, and capable of transducing second radio signals such that an impedance at the first port approaches an open circuit. An associated communication assembly and method for selectively communicating in at least two frequency bands are also provided.

Abstract: A tunable duplexer using voltage-controlled varactors is presented. The center frequency, the pass band, and the stop band are each tunable to meet system requirements. A calibration circuit driving digital to analog converters produces the necessary voltages used in the resonant circuits. The tunable duplexer can be fabricated on a single silicon chip. On-chip transformers can be used to reduce the voltage level of signals in the filters to improve the linearity of the duplexer.

Abstract: An antenna multiplexer with a pi-network circuit is described, having an inductance connected in series and, on each of the two connection sides of the inductance, a capacitance connected in parallel. The pi-network circuit is used for effecting an impedance mismatch of a signal path of the antenna multiplexer.

Abstract: For the cost effective implementation of negative-index refraction, an anisotropic hyperbolic planar metamaterial is provided. The material has a first set of substantially parallel, unloaded and coplanar transmission lines that are spaced with a periodicity dy. It has a second set of substantially parallel, unloaded and coplanar transmission lines that are spaced with a periodicity dx and are coplanar and substantially orthogonal with the first set of transmission lines. The periodicities of the first set and second set of transmission lines are governed by the relationship ?x(fr)dx+?y(fr)dy=2?, where: ?x and ?y are the intrinsic propagation constants of electromagnetic waves of frequency fr propagating along the first and second set of transmission lines, respectively.

Abstract: A signal splitter comprising an input and a plurality of outputs is provided, wherein alternate outputs are connected to phase shifting devices. The phase shifting devices preferably comprise phase shifting transformers and introduce a phase shift of 180°, so that noise components of alternate outputs are antiphase and cancel one another out almost entirely when the signals are summed. Also provided is a cable television network comprising a plurality of such signal splitters to ensure that noise ingress in upstream signals passing into the network is substantially reduced.

Abstract: A broadcasting signal processing apparatus and a control method thereof are provided. The broadcasting signal processing apparatus includes a wireless antenna; a radio frequency (RF) module which tunes a broadcasting signal; a variable part which adjusts an impedance to match an impedance of the wireless antenna with an impedance of the RF module; and a controlling part which pre-stores impedance variable values for impedance matching and which controls the variable part to adjust the impedance based on one of the pre-stored impedance variable values corresponding to a broadcasting frequency of a selected broadcasting channel. The method includes tuning to a broadcasting frequency; determining whether an impedance used to match a wireless antenna with a radio frequency (RF) module is different from an impedance variable value; and if the impedance is different, adjusting the impedance.

Abstract: A diplex filter is formed by two impedance-transforming filters with separate transmission frequency ranges and with separate cut-off frequency ranges and a connection node at which two series elements of the two filters are connected. These two series elements are each fashioned as a parallel oscillating circuit, each parallel oscillating circuit exhibiting a predetermined reactance in a midband of the respective transmission frequency range and a parallel resonance in a midband of the respective cut-off frequency range. The diplex filter can be realized in a simple and cost-effective manner without ferrite-containing special components, for instance inductively coupled coils or tapped coils thereby allowing use thereof in a magnetic resonance tomograph, for example.

Abstract: A multiplexer circuit may include a first-frequency-quarter-wavelength transmission line extending between a junction between a common terminal and a second-frequency terminal, and a first-frequency low-impedance circuit electrically directly connecting the first transmission line to a circuit ground. In some examples, a second-frequency-quarter-wavelength transmission line may extend between the first transmission line and a third-frequency terminal. A second-frequency low-impedance circuit may electrically directly connect the second transmission line to the circuit ground. The first and second transmission lines and the first and second low-impedance circuits may provide a third-frequency transmission line. A further second-frequency low-impedance circuit may electrically couple the second terminal to the first transmission line. A third-frequency low-impedance circuit may electrically couple the second terminal to the circuit ground.

Abstract: A composite high-frequency component includes a diplexer arranged to separate/combine transmission/reception signals in frequency bands of a plurality of communication systems, transmit/receive switches, filters, and a balanced-unbalanced reception signal switch, and a matching circuit. The balanced-unbalanced reception signal switch includes a reception signal switch and balanced-unbalanced filters. A stripline in the transmit/receive switch and a stripline in the reception signal switch are provided on the same layers, and the matching circuit including capacitors is arranged between the transmit/receive switch and the reception signal switch.

Abstract: There is provided a resonant circuit includes a resonator, an inductor connected in parallel with the resonator, and a capacitor connected in parallel with the resonator. There are also provided a filter and an antenna duplexer having the above-described resonant circuit.

Abstract: A transmit and receive circuit for use in power line communication devices is provided. One embodiment of the circuit includes a receive channel with a first delay circuit coupled to a first switch having an open configuration and a closed configuration a first switch. The circuit also may include a transmit channel coupled to the receive channel at a node and including a second delay circuit coupled to a second switch having an open configuration and a closed configuration. When the switch of either channel is closed, the switch of the other channel is open. Data signals traversing either channel when that channel's switch is closed, are phase shifted approximately three hundred and sixty degrees and conducted back to the node.

Abstract: A subminiature, high-performance monolithic duplexer is disclosed. The monolithic duplexer includes a substrate, a transmitting-end filter formed in a first area on an upper surface of the substrate, a receiving-end filter formed in a second area on the upper surface of the substrate, a packaging substrate, bonded on an area on the upper surface of the substrate, for packaging the transmitting-end filter and the receiving-end filter in a sealed state, and a phase shifter, formed on one surface of the packaging substrate and connected to the transmitting-end filter and the receiving-end filter, respectively, for intercepting a signal inflow between the transmitting-end filter and the receiving-end filter.

Abstract: A technology which can realize a high-performance multiband operation in a compact circuit configuration and is advantageous for a wireless terminal of GSM system for which the further increase of the demands is expected in the future is provided. Provided is a multiband switch type antenna duplexer adopted in a mobile phone used in TDMA system such as the GSM system, in which the signals of respectively different first to fourth frequency bands (GSM 850, EGSM, DCS, PCS) share a single antenna, wherein switching elements such as receive filters and diodes are combined in various ways to perform the high-performance band switch with the minimum number of switching elements. The circuit of this antenna duplexer can realize not only the size reduction of the multiband switch antenna duplexer but also the size reduction and performance improvement of the wireless terminal itself.

Abstract: A wireless communication apparatus is made up of a transmission circuit block including an antenna that is laid out such that the transmission lines, i.e., the sum of the distance connecting respective circuit blocks between an output terminal of the transmission power amplifier to an input/output terminal of the antenna is shorter than the transmission line, i.e., the sum of the distance connecting respective circuit blocks between an input terminal of a transmission power amplifier and an output terminal of a RFIC disposed at a preceding stage of the transmission power amplifier. This arrangement realizes a wireless communications apparatus ensuring improvement of overall performance of the wireless application without reducing the total transmission loss or improving the performance of individual circuits.

Abstract: A composite duplexer includes an antenna terminal, a first receiving terminal, a second receiving terminal, a transmitting terminal, a first switch, a duplexer, and a second switch. The first switch includes a first branch contact, a second branch contact connected with the transmitting terminal, a third branch contact connected with the second receiving terminal, and a first common contact connected with the first antenna terminal. The first common contact of the first switch is connected selectively with the first branch contact, the second branch contact, and the third branch contact. The first duplexer includes a first receiving filter connected with the first receiving terminal, and a first transmitting filter. The duplexer is connected with the first branch contact of the first switch. The second switch is operable to connect and disconnect electrically between the first transmitting filter of the first duplexer and the transmitting terminal.