Abstract: A transceiver front end includes a transmit/receive (T/R) switch, a first balun, a second balun, a low noise amplifier, a power amplifier, and compensation circuitry. The T/R switch is operably coupled to an antenna for receiving inbound radio frequency (RF) signals and for transmitting outbound RF signals. The first balun includes a single ended winding and a differential winding, where the single ended winding is operably coupled to the T/R switch. The second balun includes a single ended winding and a differential winding, where the single ended winding is operably coupled to the T/R switch. The low noise amplifier is operably coupled the differential winding of the first balun. The power amplifier is operably coupled to the differential winding of the second balun. The compensation circuitry is operably coupled to the first balun to compensate for at least one of phase imbalance, amplitude imbalance, and impedance imbalance of the first balun.

Abstract: A high-speed CMOS transmit/receive antenna switch includes a first transistor, a second transistor and a parasitic compensation network. The first transistor is operably coupled to an antenna, to a transmit path, and to receive a transmit/receive (T/R) control signal. The second transistor is operably coupled to the antenna, the receive path, and to receive the T/R control signal. When the T/R control signal is in a first state, the first transistor is active and the second transistor is inactive such that the transmit path is coupled to the antenna. When the T/R control signal is in a second state, the second transistor is active and the first transistor is inactive such that the receive path is coupled to the antenna. The parasitic compensation network is coupled to compensate for adverse effects of parasitic components of the first and second transistors at operating frequencies of the transmit/receive antenna switch.

Abstract: The present invention provides a high frequency module having a base substrate unit (2) which has its uppermost layer planarized to form a buildup-forming surface (16), a high frequency circuit unit (3) having multiple wiring layers which are formed on the base substrate unit (2), each of which layers has a wiring pattern and film elements formed on a dielectric insulating layer thereof, whose uppermost wiring layer (17) has plural lands (22) and ground patterns (20) formed thereon together with the wiring pattern and inductor elements (19), and a semiconductor chip (4) mounted on the wiring layer (17) of the high frequency circuit unit (3). Transmission lines (24) to connect the inductor elements (19) and lands (22) which are formed on the wiring layer (17) are directed within hollowed pattern regions (20c) formed at the ground pattern (20) to constitute coplanar type transmission lines.

Abstract: An apparatus and method for automatically matching a frequency of an antenna in a wireless terminal are provided. The apparatus includes a duplexer for classifying frequencies transmitted/received through the antenna of the wireless terminal, transmitting the reception frequency received in the antenna to an automatic matching module, and transmitting a transmission frequency, which is received from the automatic matching module, to the antenna; the automatic matching module for automatically matching impedance for the reception frequency received from the duplexer, transmitting the impedance-matched reception frequency to an amplifier, automatically matching impedance for the transmission frequency received from the amplifier, and transmitting the impedance-matched transmission frequency to the duplexer; and a controller for controlling the automatic matching module to automatically match the impedance for the transmission/reception frequencies.

Abstract: A local oscillation signal generator and a multi-band transceiver including the local oscillation signal generator are provided. The multi-band transceiver includes a fractional-N phased locked loop (PLL), a local oscillation signal generator, and a transmitter. The fractional-N PLL receives a reference signal and outputs an oscillation signal that is phase-locked to the reference signal. The local oscillation signal generator receives the oscillation signal and outputs a first divided signal that is obtained by dividing a frequency of the oscillation signal by a first value and a second divided signal that is obtained by dividing the frequency of the oscillation signal by a second value. The transmitter receives input signals and generates a transmitter signal using an equation f TX = ( 2 3 ? k - 1 M ) ? f VCO , based on the first divided signal and the second divided signal.

Abstract: A high-frequency switch circuit is provided for switching a connection between a common transmission circuit and antenna side circuit in a plurality of transmitting and receiving systems. The high-frequency switch includes a connection between the antenna side circuit and a reception circuit in one of the plurality of transmitting and receiving systems, and a connection between the antenna side circuit and a reception circuit in the other of the plurality of transmitting and receiving systems, the high-frequency switch circuit comprising a first diode; a first distributed constant line; a second diode; a capacitor; a third diode; a second distributed constant line; and a fourth diode.

Abstract: A switch circuit for selectively switching connection of an antenna side circuit with a reception circuit and a transmission circuit of two communication systems one of which has a reception frequency band partially overlapped with a transmission frequency of the other. The switch circuit includes (a) a first switch unit for switching connection of the antenna side circuit with the transmission circuit side of the first and tie second communication systems and the reception circuit side of the first and the second communication system and (b) a second switch unit connected between the first switch unit and the reception circuit of the first and the second communication system for switching connection of the antenna side circuit with the reception circuit of the first and the second communication system. (c) The transmission circuit side of the first and the second communication system of the first switch unit is connected to a transmission circuit shared by the first and the second communication system.

Abstract: A SAW communication device has a main IDT mounted on an SAW substrate to receive an RF signal received by an antenna and convert the RF signal to an acoustic wave which travels along the SAW substrate in opposite directions from the main IDT. At least two secondary IDTs are mounted on the SAW substrate on opposite sides of and spaced from the main IDT to receive and reflect the acoustic wave in a modulated form such that the modulated acoustic wave from one secondary IDT is delayed relatively to the modulated acoustic wave from a secondary IDT on the opposite side of the main IDT to the one secondary IDT. The main IDT is also operable to receive and convert the reflected modulated acoustic waves to a further RF signal with a concatenated waveform corresponding to the two modulated acoustic waves and transmit the further RF signal from the antenna.

Abstract: A communications module having a “universal” digital section and a detachable antenna section for providing compatibility with multiple communications standards. The antenna section is configured for communications with a specific communications standard, while the “universal” digital section is configured for operation with a plurality of communication standards.

Abstract: To provide a high frequency switch capable of dealing with multiple frequency bands without having plurality of switch circuits. A first diode that conducts due to a bias current when a first switch is closed is interposed between first signal terminal and a second signal terminal. A strip line with the electrical length L1 is connected to the cathode of the first diode, the other end being grounded. At a position with a distance L2 from one end of the strip line, a capacitor and a second switch are connected to be equivalently grounded when the second switch is closed. The strip line resonates with the electrical length L1 when the second switch is opened, and resonates with the electrical length L2 when the second switch is closed.

Abstract: One aspect of the present invention is generally directed towards a system and method of tuning a transducer for transmitting and receiving a wireless signal. In an illustrative embodiment, a single transducer is coupled to a first or second circuit for either transmitting or receiving, respectively. Generally, electrical characteristics of the first circuit are adjusted to increase a magnetic field generated by the transducer. Conversely, electrical characteristics of the second circuit are adjusted to increase a signal generated by the transducer for receiving a magnetic field. Accordingly, a single transducer device can be tuned for either transmitting or receiving a corresponding wireless signal.

Abstract: A high-frequency switch circuit is provided for switching a connection between a common transmission circuit and an antenna side circuit in a plurality of transmitting and receiving systems. The high-frequency switch includes a connection between the antenna side circuit and a reception circuit in one of the plurality of transmitting and receiving systems, and a connection between the antenna side circuit and a reception circuit in the other of the plurality of transmitting and receiving systems, the high-frequency switch circuit comprising a first diode, a second diode, and a distributed constant line, wherein a third diode is connected to the first and second diodes through the distributed constant line.

Abstract: A transceiver assembly including an antenna input/output transition, a transmit module, a receive module, and a diplexer. The diplexer has opposing planar surfaces and the transmit module, receive module and antenna input/output transition are placed on the same planar surface of the diplexer.

Abstract: A radio frequency (RF) switch which is used in an RF unit of a communication apparatus and which has less of an insertion loss during a transmission. A strip line disposed in the RF switch is formed by combining first and second strip lines having different values of characteristic impedance from each other.

Abstract: The present invention relates to systems and methods that employ a novel balanced duplexer that can be utilized to facilitate concurrent signal transmission and reception. The systems and methods can be employed within mobile devices such as cell phones and utilize two-filters (e.g., acoustic) with substantially similar input/output impedances interfaced with two couplers (e.g., 3 dB hybrid), which provide isolation and maintain the duplexer's input/output impedance. The couplers interface the filters to front/back ends such as signal processors, transmitters and receivers. The novel aspects of the present invention mitigate the need to employ external directional couplers between the duplexer and front/back ends. In addition, the two-filter topology enables employment of lower powered rated filters. The systems and methods further provide for separation and isolation of transmitters and receivers, which reduces noise coupling and enables the transmitter and receiver to be placed within close proximity.

Abstract: A high-speed CMOS transmit/receive antenna switch includes a first transistor, a second transistor and a parasitic compensation network. The first transistor is operably coupled to an antenna, to a transmit path, and to receive a transmit/receive (T/R) control signal. The second transistor is operably coupled to the antenna, the receive path, and to receive the T/R control signal. When the T/R control signal is in a first state, the first transistor is active and the second transistor is inactive such that the transmit path is coupled to the antenna. When the T/R control signal is in a second state, the second transistor is active and the first transistor is inactive such that the receive path is coupled to the antenna. The parasitic compensation network is coupled to compensate for adverse effects of parasitic components of the first and second transistors at operating frequencies of the transmit/receive antenna switch.

Abstract: A communication device (105) includes a first communication block (205) for operation within a first communication network (150); and a second communication block (210) for operation within a second communication network (160). The communication device (105) further includes an audio control (245) for at least one microphone (250). The audio control (245) is coupled to the first communication block (205) for receiving a first audio input for operation of the first communication block (205) and is coupled to the second communication block (210) for receiving a second audio input for operation of the second communication block (210). A low noise ground (315) is isolated from a common ground (320) of the communication device (105) to facilitate the sharing of the at least one microphone (250) between the two communication blocks.

Abstract: A SPDT switch includes an antenna port. A transmitter section is coupled to a transmitter port. The transmitter section includes a plurality of transistors that are coupled in series relative to each other. A receiver section is coupled to a receiver port. The receiver section includes a plurality of transistors that are coupled in series relative to each other, so that when the transmitter section transmits high power to the antenna port, the receive section is effectively off to provide isolation to the receive port. The receiver port is coupled to the receiver section using at least one external capacitor. The at least one external capacitor is used to improve the power handling capability and harmonic performance of the switch.

Abstract: The present invention relates to a self-adaptive band-pass filtering device in a microwave signal transmitter and/or receiver, the receiver being connected to a microwave signal receiving antenna connected to the input of a low-noise amplifier, a mixer that receives, on the one hand, the output signal of the low-noise amplifier and, on the other hand, the signal from a frequency synthesizer, characterized in that the self-adaptive filtering device comprises, upstream of the amplifier, on the one hand, at least one filtering means having at least two different frequency bands and, on the other hand, means for selecting either a filtering means or one of the frequency bands depending on the frequency of the signal to be received.

Abstract: A transceiver having a transmit/receive switch. The transmit/receive switch includes: a common port adapted for coupling to an antenna element; a transmit port; a receive port and a matched port. The transceiver includes a second switch. The second switch has: a common port adapted for coupling to an input/output port through a gain/phase control unit; a transmit port; a receive port and a matched port. The transceiver includes a balanced amplifier. The balanced amplifier includes a pair of input ports. A first one of the pair of input ports is coupled to receive port of the transmit/receive switch, and a second one of the pair of input ports is coupled to the transmit port of the second switch. The balanced amplifier includes a pair of output ports. A first one of the pair of output ports is coupled to the transmit port of the transmit/receive switch and a second one of the pair of ports is coupled to the receive port of the second switch.

Abstract: A portable radio terminal comprises a housing, a radio circuit included in the housing, a matching circuit mounted on the top of the housing at a position which is offset from the longitudinal center line of the housing, a load connected to the tip of the matching circuit, and a linear antenna connected to the load. This portable radio terminal further comprises load changing means for changing the value of the load. The matching circuit may comprise a meander matching element, a zigzag-shaped matching element, a helical matching element, a conical matching element, a rectangular helical matching element or a pyramid helical matching element which are formed so as to a predetermined shape, such as a meander shape, a zigzag shape, a helical shape, a conical shape, a rectangular helical shape or pyramid helical shape.

Abstract: A communication card or communication device is provided that includes an antenna for transmitting/receiving communication waves; a variable matching unit which can vary a circuit parameter; a directional coupling unit for extracting a reflected signal from the antenna; a detection unit for extracting the amplitude of the reflected signal; a control unit for outputting a control signal; an amplifier for amplifying a high frequency signal at a RF band; a frequency converter for converting an IF band signal into a RF band signal or a RF band signal into an IF band signal; a modulator/demodulator for modulating an IF signal to obtain a baseband signal at the transmission and demodulating an IF signal to obtain a baseband signal at the receiving; a baseband processor for processing the baseband signal; and a card interface for exchanging data with an information device.

Abstract: A radio frequency switching apparatus wherein a filter for a transmitter module passes a transmission frequency to an antenna in a transmission mode and isolates the antenna and the transmitter module from each other in a reception mode. The radio frequency switching apparatus comprises a filter connected between the transmitter module and the antenna for passing a transmitted signal from the transmitter module to the antenna in the transmission mode. The filter also acts to cut off a reception frequency in the reception mode. The switching apparatus further comprises a first switching device for isolating the transmitter module and the antenna from each other in the reception mode, and a second switching device for isolating the antenna and a receiver module from each other in the transmission mode. No separate ¼ wavelength strip line is required, making the circuitry of the switching apparatus simpler and, thus, the size thereof smaller.

Abstract: A high-frequency switch module comprising one band-separating circuit and two switch circuits, the first switch circuit being connected to one circuit separated by the band-separating circuit, and the second switch circuit being connected to the other circuit thereof; the first switch circuit being a circuit for switching a transmission system and a reception system for a first transmitting and receiving system; and the second switch circuit being a circuit for switching a transmission system and a reception system for a second transmitting and receiving system and a transmission system and a reception system for a third transmitting and receiving system.

Abstract: A foldable portable radio terminal is disclosed which normally optimizes an antenna characteristic by an antenna matching circuit even if the body length of the foldable portable radio terminal varies. A folded state detection circuit sends a detection signal to a control section depending upon whether or not the foldable portable radio terminal is folded. An antenna matching circuit is determined so that the antenna characteristic of an antenna is optimized when the foldable portable radio terminal is in a folded state. When the foldable portable radio terminal is unfolded, the control section renders a matching characteristic changeover circuit operative to change over the matching characteristic of the antenna matching circuit so that, even when the foldable portable radio terminal is in an unfolded state, the antenna characteristic by the antenna matching circuit may be optimized.

Abstract: The present invention provides a transceiver apparatus that permits miniaturization even when the antenna thereof is an unbalanced circuit and the transmitter circuit section and receiver circuit section thereof are balanced circuits. The transceiver apparatus is constituted comprising: a semiconductor integrated circuit device that mounts on the same semiconductor chip a balanced receiver circuit 41 for receiving a received signal as a differential input and balanced transmitter circuit 52 for outputting a transmitted signal as a differential output, and that has at least two terminals 71,72 connected to connecting nodes that connect the balanced receiver circuit 41 and the balanced transmitter circuit 52; first and second capacitors C2,C3 connected to the terminals 71, 72 respectively; an external inductor L1 connected to the first and second capacitors C2, C3; a band pass filter 2 and an antenna 1 coupled to the first capacitor C2; and a third capacitor C1 connected to the second capacitor C3.

Abstract: A high frequency switching device includes a control terminal, a power source terminal, a GND terminal, an RF terminal, a switch section, a control section, and protecting diodes. The switch section switches input/output routes of an RF signal input from the RF terminal. The control section controls the switching section, and is connected to the control terminal and the power source terminal. The protecting diodes are provided between the control terminal and the RF terminal, between the control terminal and the GND terminal, and between the power source terminal and the GND terminal.

Abstract: The invention relates to a mobile terminal antenna system for a first radio application (RA1) and a second radio application (RA2) the system comprising first radio electronic circuits (REC1) for the first radio application (RA1), and second radio electronic circuits (REC2) for the second radio application (RA2). The system also comprises an end-fed antenna (4) for the first radio application (RA1), the end-fed antenna (4) having an extended shape and being connected to the first radio electronic circuits (REC1). The system comprises a dipole antenna (5) for the second radio application (RA2), the dipole antenna (5) being located near one end of the end-fed antenna (4) and connected to the second radio electronic circuits (REC2).

Abstract: For the purpose of making the system more economic, given full compensation of transmitter and receiver signal attenuation in the communication cable, the circuit controlling transmitter enable/disable status, including a controllable power source (control command converter) and a low pass filter separating a receive/transmit UHF signal from a lower frequency up to direct voltage) signal, a number of control commands, is introduced into mobile station, mobile station having autonomous power supply. According to the first variant of the device, the control command, having passed the low pass filter (19), enables the power source (21) control from which power is supplied to the power amplifier (11) whose amplification is selected so as to compensate attenuation of the transmitter signal traveling from mobile station (1) to antenna (16).

Abstract: It is an object of the invention to provide a connection structure for connecting the dielectric strip of an NRD guide with a metal waveguide, in which the conversion loss (connection loss) for high-frequency signals is reduced, and in which the NRD guide as well as the millimeter wave integrated circuit in which the NRD guide is incorporated can be made smaller. A non-radiative dielectric waveguide is made by arranging a dielectric strip for propagating high-frequency signals between parallel planar conductors arranged at a spacing of not more than half the wavelength of a high-frequency signal, a conductive member being arranged at an end face of a terminal end of the dielectric strip. An aperture is formed in at least one of the parallel planar conductors at a location where the electrical field of an LSM mode stationary wave propagating along the dielectric strip becomes largest. An open terminal end of a metal waveguide is connected to this aperture.

Abstract: A device for matching an antenna impedance in a portable radio telephone having transmission and receiving circuits, a foldable casing enclosing the radio, the foldable casing movable between an unfolded position and a folded position, an antenna movable between an extracted position from the foldable casing and a retracted position into the foldable casing includes means for sensing whether the foldable casing is in the unfolded position and for sensing whether the antenna is in the extracted position, and for providing a sensing signal in response thereto, and means for matching an impedance of the antenna and an impedance of the radio in response to the sensing signal, thereby making an optimal matching of impedances between the antenna and the radio according to the states of the folder casings and the antenna, and according to the transmission/reception mode.

Abstract: A multiband high-frequency switch that is mainly used for mobile phones, comprising a strip line formed of the series connection of first and second strip lines. A second transmitting port is connected to the connection point of the strip lines connected in series via a third diode, and a second control port is connected between the second transmitting port and the third diode. In addition, first and second receiving ports are connected to the receiving-side port of the high-frequency switch via a diplexer.

Abstract: An apparatus for transferring electromagnetic energy intermediate a host device and a medium or free space adjacent to the apparatus in an impulse radio system includes: (a) an energy guiding means for guiding the electromagnetic energy; the energy guiding means is connected with the host device; (b) an electromagnetic energy channeling structure effecting the transferring and including a plurality of gap interfaces; and (c) a transition means for coupling the energy guiding means with at least one gap interface of the plurality of gap interfaces. The transition means conveys the electromagnetic energy intermediate the energy guiding means and the at least one gap interface. The at least one gap interface intersects the transition means in a substantially continuous curve in selected planes intersecting the gap interface and the transition means.

Abstract: The present invention relates to an arrangement for connecting antennas to ports of a transceiver unit in a base station. By using two circulators and a four port sputter a more flexible small base station is attained. The arrangement provides, at a low extra cost, the capability of adding an auxiliary transceiver unit to the base station.

Abstract: A front end module comprises a diplexer, a first duplexer, and a second duplexer. The first duplexer is connected to the diplexer through a first high frequency switch and separates transmission signals and reception signals of the N-CDMA from each other. The second duplexer is connected to the diplexer through a second high frequency switch and separates transmission signals and reception signals of the W-CDMA from each other. Each of the duplexers includes acoustic wave elements. A single multi-layer substrate for integration is used to integrate the components of the front end module. The diplexer is made up of a conductor layer located inside or on the surface of the multi-layer substrate.

Abstract: An antenna sharing system and method. In the illustrative embodiment, the inventive system includes a first matching network coupled to a first circuit; a second matching network coupled to a second circuit; and a switch having a first throw coupled to the first network, a second throw coupled to the second network, and a pole coupled to the antenna. In the specific implementation, the first circuit is a cellular subsystem and the second circuit is a Global Positioning System subsystem. The system further includes a controller for selectively actuating the switch whereby the first network is coupled to the antenna in a first operational mode and the second network is coupled to the antenna in a second operational mode. In the illustrative implementation, the first network provides an impedance match to the switch and the antenna with respect to the first circuit. The second network provides an impedance match to the switch and the antenna with respect to the second circuit.

Abstract: A mobile radio machine of folding type with simple structure which can receive a pull-out type whip antenna and function as antenna even when the antenna is restored is disclosed. In the mobile radio machine, when the antenna is pulled out, a change-over circuit 8 connects a radio circuit 12 with an impedance matching circuit 9 and supplies power to a linear antenna element 1 through a feeding terminal 5, so that only the linear antenna element 1 functions as antenna. When the antenna is restored, the change-over circuit 8 connects the radio circuit 12 with an impedance matching circuit 10 and supplies power to a coil antenna element 3 through a feeding terminal 6, and therefore only the coil antenna element 3 functions as antenna. Thus, antenna can be used in a small size, folding type mobile radio machine in simple structure.

Abstract: A circuit for matching an amplifier to a radio-frequency line is described. In order to minimize the number of components required for matching the amplifier to different frequency bands, the circuit has a first capacitance for outputting the negative half-cycle of the transmission signal, which is rectified by a diode and is stored in a second capacitance. The stored negative voltage is, if required, fed back via two resistors and an inductance to a further diode.

Abstract: A high-frequency module includes a diplexer, first and second high-frequency switches, a SAW duplexer, first and second LC filters functioning as first and second filters, and an SAW filter functioning as a third filter. The module defines a unit that integrates front-end sections of first to third communication systems, a digital cellular system (1.8 GHz band), a personal communication service (1.9 GHz band) and a global system for mobile communications (900 MHz band).

Abstract: An economical, compact wireless data telemetry transceiver is adapted to establish and maintain communication links at 2.4 GHZ. The wireless transceiver includes RF and computer control components in a compact package approximately the size of a deck of cards and is adapted to be built into original equipment manufacturer (OEM) products to support a wide range of wireless data telemetry applications. Each transceiver includes a shielded RF board or module with a frequency hopping transmitter and receiver, an antenna, and a digital control board or module. The transceiver functions as a half duplex, bi-directional communication device; transmit and receive functions are time interleaved in a non-overlapping fashion. The RF Board consists of a transmitter, receiver, frequency synthesizer and T/R Switch, each controlled by an external microprocessor to either transmit serial data or receive serial data.

Abstract: An antenna interface for a Time Division Duplex (TDD) radio transceiver allows a transceiver to be attached to an antenna/filter without the need for an antenna switch. The antenna interface includes a single Balun circuit to convert a single-ended signal to/from differential signals, and a single impedance matching circuit to match an impedance at an output of the single Balun circuit with an input impedance of a Low Noise Amplifier (LNA) of a receiver and to provide an output impedance of a Power Amplifier (PA) of a transmitter. The single impedance matching circuit is coupled to both the LNA and the PA. The LNA and the PA are based on CMOS technology and made within a single integrated circuit.

Abstract: In a multiple portable phone, a first antenna is provided for a first communication system, a second antenna is provided in common to the first communication system and a second communication system. A switching circuit is controlled based on a control signal. A receiving circuit for the first communication system is connected to one of the first and second antennas via the switching circuit. A transmitting and receiving circuit provided for the second communication system is connected to the second antenna. A control unit generates the control signal to control the switching circuit to connect the impedance matching circuit to a path from the second antenna to the transmitting and receiving circuit when the transmitting and receiving circuit carries out a receiving operation using the second antenna while the receiving circuit carries out a receiving operation using the first antenna.

Abstract: An apparatus for communication of electric or electromagnetic signals over air includes a transmitter or receiver and a coupler. The coupler has a capacitive circuit connected with an air-core or dielectric-core transformer. The capacitive circuit resonates with the transformer at a preselected frequency. The coupler eliminates noise and is matched to the characteristic impedance of the air at the preselected frequency, which linearizes communication and allows high-speed data and voice communication over long distances.

Abstract: A portable radio terminal comprises a housing, a radio circuit included in the housing, a matching circuit mounted on the top of the housing at a position which is offset from the longitudinal center line of the housing, a load connected to the tip of the matching circuit, and a linear antenna connected to the load. This portable radio terminal further comprises load changing means for changing the value of the load. The matching circuit may comprise a meander matching element, a zigzag-shaped matching element, a helical matching element, a conical matching element, a rectangular helical matching element or a pyramid helical matching element which are formed so as to a predetermined shape, such as a meander shape, a zigzag shape, a helical shape, a conical shape, a rectangular helical shape or pyramid helical shape.

Abstract: An antenna system with two antennas provides the possibility to operate at least two different radio communication systems with one radio communication system operating on one single antenna of the antenna system and another radio communication system operating on both antennas of the antenna system wherein the antenna system serves as a diversity antenna system. This kind of antenna system is designed to be employed particularly in small devices with restricted measurements. Especially, an implementation of an antenna system for dual use of GSM/E-GSM/DCS operation and WLAN operation is presented.

Abstract: The present invention relates to a self-adaptive band-pass filtering device in a microwave signal transmitter and/or receiver, the receiver being connected to a microwave signal receiving antenna (1) connected to the input of a low-noise amplifier (2), a mixer (4) that receives, on the one hand, the output signal of the low-noise amplifier (2) and, on the other hand, the signal from a frequency synthesizer (5), characterized in that the self-adaptive filtering device (3) comprises, upstream of the amplifier (2), on the one hand, at least one filtering means (300, 31, 32) having at least two different frequency bands and, on the other hand, means (8, 33, 34) for selecting either a filtering means (31, 32) or one of the frequency bands depending on the frequency of the signal to be received.

Abstract: A wireless network card includes an adaptable antenna connection structure that includes connections for one or more internal antennas and for one or more Radio Frequency (RF) connectors that may be coupled to one or more external antennas. A Printed Circuit Board (PCB) and electronic components located thereon form the wireless network card. The PCB includes a removable portion that, when removed, leaves an opening that receives an RF antenna connector. When the PCB is used to create a client wireless network card, one or more surface mount antennas are mounted on the PCB and coupled to surface mount antenna conductive pads formed thereon. The wireless network card may include (1) the surface mount antenna; (2) the RF connector; or (3) both the surface mount antenna and the RF connector.

Abstract: A diplexer for providing an efficient, low cost, passive, reliable system and method for sharing a single antenna between a cellular subsystem and a GPS subsystem. The inventive diplexer includes first and second devices coupled to an input node for receiving a composite signal having first and second component signals at first and second frequencies respectively. In accordance with the invention, the first device passes the first signal and provides an open circuit to the second signal, while the second device passes the second signal and provides an open circuit to the first signal. In the illustrative embodiment, the first and second devices are first and second transmission lines respectively. The transmission lines may be of any type, i.e., microstrip, stripline, coplanar waveguide etc.

Abstract: A transceiver front-end provides an interface between a transmission medium and transmitter, and between a transmission medium and receiver. The transceiver front-end includes a hybrid circuit, a high-pass filter, and a gain stage, that permits the reduction or the complete elimination of buffer amplifiers. Buffer amplifiers can be eliminated because the hybrid circuit and/or the high-pass filter are adapted so that they can be directly connected to each other, without a loss in circuit performance. Furthermore, the high-pass filter and/or the gain stage are also adapted so they can be directly connected. As such, the transceiver front-end can be constructed using all passive components, reducing or eliminating excess heat generation.

Abstract: A transceiver system is disclosed for use in a telecommunication system. The transceiver system includes a transmission circuit including a transmitter input coupled to an input of a transmission amplifier, a receiver circuit including a receiver output coupled to an output of a receiver amplifier, and a transmission line interface circuit that is coupled to an output of the transmission amplifier and to an input of the receiver amplifier. The transmission line interface circuit includes a matching impedance that is directly coupled to a feedback path of the transmission amplifier and that terminates the transmission line of the transceiver system.