Abstract: A multi-band filter module and a method of fabricating the same are provided. The multi-band filter module includes a piezoelectric substrate, a first filter provided on the piezoelectric substrate, and a second filter provided adjacent to the first filter on the piezoelectric substrate, and operating in a frequency band that is lower than that of the first filter.

Abstract: An RF nanoswitch which can reduce a loss in RF signal. The RF nanoswitch includes a first electrode unit connected to one terminal of a driving power supply, a second electrode connected to the other terminal of the driving power supply, and a dielectric material selectively coming into contact with at least one of the first electrode unit and the second electrode, depending on whether or not power is applied from the driving power supply.

Abstract: A MEMS switch includes a lower substrate having a signal line on an upper surface of the lower substrate; an upper substrate, having a cavity therein, disposed apart from the upper surface of the lower substrate by a distance, and having a membrane layer on a lower surface of the upper substrate; a bimetal layer formed in the cavity of the upper substrate on the membrane layer; a heating layer formed on a lower surface of the membrane layer; and a contact member formed on a lower surface of the heating layer. The contact member can come into contact with or separate from the signal line. A method for manufacturing the MEMS switch includes preparing the upper and lower substrates and combining them so that a surface having the signal line faces a surface having the contact member and the upper and lower substrates are disposed apart by a distance.

Abstract: A mobile terminal communicates with a base station to request channel allocation for RFID communication, receives a channel from the base station, and communicates with an RFID tag through the allocated channel.

Abstract: A packaging chip having inductors therein is provided. The packaging chip includes a substrate for mounting a circuit element therein, at least one port formed on a surface of the substrate, a sealing portion electrically connected on the substrate to the circuit element and the at least one port, respectively, and a packaging substrate bonded to the substrate through the sealing portion and packaging the circuit element. In this case, the sealing portion has a certain magnitude of inductance since it is formed of a conductive material, thereby serving as an inductor. Accordingly, the packaging chip having an inductor therein can be implemented in a small size.

Abstract: A micro electromechanical system (MEMS) device package and a method of manufacturing the same are provided. The MEMS device package includes: a device substrate with a MEMS active device being formed on the top surface thereof; internal electrode pads, each of which is positioned on the opposite side of the MEMS active device and electrically connected to the MEMS active device; sealing pads positioned outside of the internal electrode pads; a closure substrate joined to the device substrate through the sealing pads, the closure substrate having via holes formed at the areas where the internal electrode pads are positioned; and external electrode pads formed on the top surface of the closure substrate in such a way that the external electrode pads are electrically connected to the internal electrode pads through the via holes.

Abstract: A filter formed of film bulk acoustic resonators has a topology that enables a trimming inductor to be fabricated on the same substrate as the resonator arrays. The entire filter can be fabricated on a single chip, utilizing only integrated circuit processes. In an exemplary embodiment, a pair of shunt resonators each have one electrode connected to series-connected resonators. The other electrodes of the two shunt resonators are connected in common to one another. The trimming inductor is connected between the common electrode and ground potential. A third shunt resonator is connected between the series-connected resonators and ground potential.

Abstract: A balun includes an input line for receiving an unbalanced signal, an output line for receiving the unbalanced signal from the input line and outputting a balanced signal, and a ground. The input line and the output line are formed in the same layer, and the ground is formed in a different layer from the input line and the output line. The ground has an opening so as to generate a potential difference between the first output line and the second output line. The ground is electrically connected to the input line.

Abstract: A band pass filter for improving filtering, realizing high integration, and reducing manufacturing costs, and a duplexer having the band pass filter. The band pass filter comprises a first resonant circuit in which n first resonators are connected in series, where n is a natural number greater than 1; a second resonator circuit which faces the first resonant circuit and has m second resonators connected in series, where m is a natural number greater than 1; and a third resonant circuit in which k third resonators are connected in parallel on branching lines linking the first and second resonant circuits, where k is a natural number greater than 1. By arranging the resonators of the respective resonant circuits in the bridge structure, the filtering characteristics can be improved, the number of inductors used to adjust the resonant frequency characteristics of the resonators can be reduced, high integration can be realized and manufacture cost can be reduced.

Abstract: A duplexer is provided. The duplexer includes a first band pass filter (BPF) coupled to a first signal port and a second signal port; and a second BPF coupled to the first signal port and a third signal port, each of the first BPF and the second BPF including a first resonance circuit which comprises a plurality of first resonators coupled in series; a second resonance circuit which comprises a plurality of second resonators coupled in series; and a third resonance circuit which comprises a plurality of third resonators coupled in parallel and formed in divided lines coupling the first and second resonance circuits.

Abstract: A multi-band filter module and a method of fabricating the same are disclosed. At least one upper filter is deposited on an upper surface of a first substrate. The first packaging substrate packages the upper filter deposited on the first substrate. At least one lower filter is deposited on an upper surface of the second substrate. The second packaging substrate packages the lower filter deposited on the second substrate. The lower surface of the first substrate is joined to a lower surface of the second substrate to face each other.

Abstract: A Radio Frequency (RF) transmission method of a Radio Frequency Identification (RFID) reader using a plurality of channels is provided. The method includes: selecting at least part of the plurality of channels, measuring an RF power of each of the selected channels, determining a transmission environment of the RF according to a measurement determination, and modulating an RF signal according to the determined transmission environment.

Abstract: A radio frequency identification (RFID) reader includes a transmitter generating a transmission signal for transmission to a tag, a receiver receiving a response signal from the tag, a leakage compensator compensating a leakage signal leaked from the transmitter to the receiver in response to a leakage control signal, and a control unit performing a leakage test operation by applying a test signal to the transmitter, and calculating and storing a leakage parameter for generating the leakage control signal using a level difference of the test signal and a level difference of a test leakage signal leaked to the receiver.

Abstract: A balun capable of a reduced whole size. The balun includes an input line receiving an unbalanced signal, an output line receiving the unbalanced signal from the input line and outputting a balanced signal, and a ground part. The input and output lines are formed on a layer, and the ground part is formed on a different layer from the layer. The ground part includes an opening and is electrically connected to the input line, and a portion of the ground part is removed to form the opening so that a potential difference occurs between first and second output lines. Thus, although a length of the output line is less than ¼ of an input wavelength ?, a difference between phases of first and second output signals can be about 180°. As a result, the whole size of the balun can be reduced.

Abstract: An integrated filter including a film bulk acoustic resonator (FBAR) and a surface acoustic wave (SAW) resonator and a method of fabricating the integrated filter. The integrated filter includes: a substrate; a first electrode positioned in a predetermined first area on an upper surface of the substrate; a first piezoelectric layer positioned on the first electrode; a second electrode positioned on the first piezoelectric layer; a second piezoelectric layer positioned in a predetermined second area on the upper surface of the substrate; and at least one inter-digital transducer (IDT) electrode positioned on the second piezoelectric layer. The IDT electrode includes: a first IDT electrode formed in a comb structure on the second piezoelectric layer; and a second IDT electrode formed in a comb structure on the second piezoelectric layer so as to mesh with the first IDT electrode. The first and second piezoelectric layers are formed of an identical material.

Abstract: An integrated device is constructed by integrating an FBAR and a tunable capacitor. The integrated device includes a substrate; a resonator formed on the substrate; a driving electrode layer formed on the substrate apart from the resonator; a first electrode layer formed upwardly apart from the substrate and facing the resonator; and a second electrode layer formed upwardly apart from the substrate and facing the driving electrode layer, the second electrode layer stepped from the first electrode layer. Accordingly, the integrated device can increase the tuning range and mitigate the parasitic resistance.

Abstract: A film bulk acoustic resonator (FBAR) filter and a duplexer are disclosed. At least one series resonator is positioned between an input port for inputting a frequency signal and an output port for outputting a frequency signal, at least two shunt resonators respectively positioned between the input and output ports and a ground, a first trimming inductor connects the at least two shunt resonators and the ground, and a second trimming inductor is positioned between the at least two shunt resonators.

Abstract: A balance filter packaging chip having a balun mounted therein and a manufacturing method thereof are provided. The balance filter packaging chip includes a device substrate; a balance filter mounted on the device substrate; a bonding layer stacked on a certain area of the device substrate; a packaging substrate having a cavity formed over the balance filter, and combined with the device substrate by the bonding layer; a balun located on a certain area over the packaging substrate; and an insulator layer for passivating the balun. Accordingly, the present invention can reduce an element size and simplify a manufacturing process.

Abstract: A multi-band filter module and a method of fabricating the same are provided. The multi-band filter module includes a piezoelectric substrate, a first filter provided on the piezoelectric substrate, and a second filter provided adjacent to the first filter on the piezoelectric substrate, and operating in a frequency band that is lower than that of the first filter.

Abstract: A phase shifter fabricated by a simple process and having a simple structure, a method of fabricating the same, and a duplexer having the same are disclosed. The duplexer includes a transmitting-end filter capable of passing only a signal in the range of a transmission frequency, a receiving-end filter capable of passing only a signal in the range of a reception frequency, and a phase shifter interposed between the transmitting-end filter and the receiving-end filter to isolate a transmitted signal of the transmitting-end filter and a received signal of the receiving-end filter from each other. The phase shifter includes a substrate provided with an input port and an output port, an inductor formed on the substrate and connected to the input and output ports, and a capacitor provided on the substrate, wherein the capacitor and inductor share a region of the substrate.