Abstract: The invention provides a system for implementing a high capacity MIMO system with high throughput which will ensure an eigenmode rich channel largely irrespective of the environment. In conventional MIMO systems, the environment can substantially reduce the theoretically achievable throughput if there is little angular diversity. The system includes a scattering structure for scattering beams emitted by an antenna array to provide good angular diversity at the receiver and hence good throughput in all environments. In addition, the scattering structure is controllable to allow its properties and hence the eigenmodes generated to be varied to maximise the efficiency of the system.

Abstract: An electronic apparatus has a first radio module configured to use a first frequency band, a second radio module configured to use a second frequency band which is different from the first frequency band, an antenna coupled to both the first radio module and the second radio module, a dielectric material, and a mechanism configured to relatively move the dielectric material with respect to said antenna so that an interval between the antenna and the dielectric material is changed between a first interval for the first radio module and a second interval for the second radio module.

Abstract: A radio frequency (RF) module for use in a communication device of a communication system includes integrated RF circuitry comprising at least one of a transmitter and a receiver, and an antenna element having at least one portion thereof arranged substantially adjacent to and operatively coupled to the integrated RF circuitry. For example, the antenna element may include at least first and second portions having opposing edges arranged immediately adjacent respective first and second sides of the integrated RF circuitry. A plurality of the modules can be used to implement a transceiver in a communication system base station or other communication device.

Abstract: A composite high frequency component which can be used in three different communication systems and a mobile communication apparatus which includes the same are provided. The composite high frequency component includes a first high frequency switch having a first common port and first, second, and third communication ports. The first communication port is connected to the transmitting sections of first and second communication systems. The second communication port is connected to a receiving section of the first communication system. The third communication port is connected to a receiving section of the second communication system. The composite high frequency component also includes a second high frequency switch having a second common port and fourth and fifth communication ports. The fourth communication port is connected to a transmitting section of a third communication system. The fifth communication port is connected to a receiving section of the third communication system.

Abstract: A tunable antenna matching circuit is provided. The matching circuit includes a ferro-electric tunable component. A control signal is applied to the tunable component, changing the component's impedance. This changes the impedance of the matching circuit.

Abstract: The invention relates to apparatus, methods and computer program code for equalisation. A soft-in-soft-out (SISO) equaliser for use in a receiver for receiving data from a transmitter configured to transmit data from a plurality of transmit antennas simultaneously is described.

Abstract: A circuit and method for reducing local oscillator frequency transmission in a homodyne, or direct conversion, radio transceiver using I/Q modulation/demodulation minimizes local oscillator leakage to the antenna and its subsequent reception by the receiver by interfacing I/Q input signals to the modulator in a controlled manner so as to increase isolation during reception by presenting high impedance states to the I/Q modulator input terminals during reception thereby nulling the carrier during reception.

Abstract: An apparatus, system, method and computer program product for digital beamforming in the IF domain. The beamforming technique of the present invention can be implemented in general point-to-multipoint wireless networks to significantly increase bandwidth in both the downlink and uplink directions. This beamforming technique allows for a modular design of a smart antenna system which typically includes an antenna array, a multiple number of transceivers, IF beamformers, and a set of modems.

Abstract: There is disclosed a receiver which solves such a problem as to strictly realize channel selection filter characteristics in extracting a narrow band signal from a broad band signal by digital signal processing in a conventional direct conversion circuit and which improves an image rejection ratio and which can reduce a load of hardware or processing to realize a channel selection filter for extracting the narrow band signal.

Abstract: A system that provides packaging for a surface acoustic wave filter in such a way that the surface acoustic wave filter is capable of integration with a number of additional electronic devices on an integrated substrate. The surface acoustic wave filter is mounted in a “flip chip” configuration that enables the surface of the surface acoustic wave filter to be protected from a molding compound during and after the encapsulation of the surface acoustic wave filter and other circuitry contained on the integrated substrate. The manner in which the surface acoustic wave filter is packaged provides a great reduction in cost and occupied real estate on the integrated substrate, in that, the surface acoustic wave filter is mounted in such as way as not to require conventionally used ceramic packaging that encases the surface acoustic wave filter. An air gap is preserved between the surface acoustic wave filter side of the surface acoustic wave filter and the integrated substrate on which it is mounted.

Abstract: A method and device for using a single antenna for simultaneously receiving radio frequency signals in different L-band and GPS data band radio frequency bands embodied by example in a circuit having a directional coupler configured to direct a signal input at a first port into two second ports. Filters are coupled to receive the output of each second port, the filters being configured to reflect radio frequency energy in radio frequency bands other than the GPS data radio frequency band. The directional coupler is further configured to direct the reflected radio frequency energy into another port of the directional coupler. A filter is coupled to the other port of the directional coupler and is configured to reflect radio frequency energy in radio frequency bands other than the L-band radio frequency.

Abstract: A method for determining an antenna beam angle for base stations of a radiotelecommunication system, notably of the cellular mobile radiotelephony system type. Each of the base stations defines a cell and has a transmission and reception antenna whose beam covers a sector in which mobile units can communicate with the base station. The antenna beam can be inclined, so as to modify the sector covered, via a dynamic antenna beam inclination control method. That method includes the steps of determining, a priori, an optimum inclination that is optimum in relation to the sector covered; estimating a cell load of the cell at a given instant; determining an instantaneous inclination at the given instant, as a function of the optimum inclination and the estimated load; controlling an instantaneous inclination of the antenna as a function of the instantaneous inclination determined.

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: Disclosed is an apparatus for commonly using an antenna for a call signal and a television (TV) broadcasting signal in a radio communication terminal including an antenna, a phone duplexer, a TV tuner, an LC parallel circuit, connected between the antenna and the phone duplexer, for forming an LC resonance circuit for a call signal frequency band, an LC series circuit connected to a connected point of the LC parallel circuit and the antenna and to a DC power supply terminal, a stub for impedance matching one terminal of which is connected between a capacitor and an inductor of the LC series circuit and the other terminal of which is connected to the TV tuner, and a path providing section for providing a path between a connected point of the stub and the TV tuner and a ground terminal in accordance with a switching control signal provided according to a TV or call operating mode.

Abstract: The object of the invention is a transceiver for transmitting and receiving an RF signal on at least two operating frequency ranges. One idea of the invention is to use a transceiver based on the direct transform and where the mixing frequency is generated with the aid of the same synthesiser. This is preferably realised so that when operating on frequency ranges far from each other the output signal of the synthesiser is divided with different divisors in order to generate the mixing frequency (211, 231, 261, 281). When operating on frequency ranges which are close to each other the divisor (P) used in the feedback of the synthesiser is advantageously changed (248). With the aid of the invention two mixing signals with a mutual phase difference of 90 degrees can be generated in connection with the division of the synthesiser frequency, whereby no RC phase shifters are required in the signal line, and a good phase accuracy is obtained which is independent of the frequency.

Abstract: Provided is a high-frequency circuit apparatus and a communication apparatus whose consumption current is small and the inserting loss is small. One embodiment provides a high-frequency circuit apparatus constructed by an antenna duplexer of a frequency variable type; a first change-over switch which is electrically connected to an antenna terminal in the antenna duplexer; a second change-over switch which is electrically connected to a receiving terminal in the antenna duplexer; and a filter for reception which is electrically connected across the first and second change-over switches. As for the first and second change-over switches, a GaAs switch and a PIN diode switch, etc. are used. As for the filter for reception, a surface acoustic wave filter or monolithic ceramic LC filter, etc. is used.

Abstract: Multiple power amplifiers in an RF front end are coupled to multiple antennas without diversity switching between the PAs and antennas. Diversity switches direct signals to broadcast by a selected antenna to a PA coupled to the selected antenna. Multiple LNAs are similarly coupled to the diverse antennas. Having one PA and LNA set for each antenna removes the need for diversity switching between the PA/LNAs and each antenna improving signal reception. In one embodiment, a single external PA performs broadcast functions and plural on-chip LNAs are used for reception. In another embodiment, phase shifters are coupled to each PA and LNA, which provide beam forming capability for broadcasts, and in phase signal combinations for received signals.

Abstract: An antenna for a mobile telephone, in which a radiation source of the antenna is separated from the user's head while the mobile telephone is in use, to prevent an influence of the radiation waves on the user's head and prevent the non-directional property of the radiation pattern from being degraded. The mobile telephone comprises an antenna body for transmitting and receiving radio waves; a terminal for performing communication based on the radio waves transmitted and received by the antenna body; and a support for maintaining (or supporting) the antenna body to be higher by a predetermined height than the terminal, when the mobile telephone is in use.

Abstract: Transmitting apparatus (10) for transmitting a transmission signal to a receiving apparatus (12) is described. The transmitting apparatus (10) comprises means (30, 32, 34) for transmitting to the receiving apparatus a plurality of transmission beams in accordance with a transmission beam pattern, at least one of the beams carrying the transmission signal, each beam being distinguishable from the or each other beam, means (38, 40) for receiving from the receiving apparatus a feedback signal based on measures of the quality of the transmission beams received at the receiving apparatus, and means (36) for adjusting the transmission beam pattern in dependence on the feedback signal. Corresponding receiving apparatus, and corresponding methods are also described.

Abstract: An arrangement where a transmitter has multiple transmitting antennas that simultaneously transmit, and where the signals delivered to each transmitting antenna is processed by a space-time transmitter based on the side information that is related to the channel coefficients found between the transmitting antennas and multiple receiving antennas. The receiver's receiving antennas simultaneously receive the transmitted signals, and the signal from each receiving antenna is processed by the space-time receiver to extract the information symbols that have been transmitted. Alternative systems are possible, such as those employing frequency or code diversity, as well as those employing only one transmit antenna and multiple receive antennas (or visa versa).

Abstract: According to some embodiments of the present invention, an impedance transformation circuit is provided for use with a transmitter, a receiver, and an antenna. The transmitter may provide transmission signals for transmission by the antenna. The antenna may provide received signals having an associated signal parameter to the receiver. The impedance transformation circuit includes an impedance adjusting circuit and a controller. The impedance adjusting circuit is connected between the antenna, the receiver, and the transmitter. The impedance adjusting circuit is configured to change an impedance difference presented between at least one of: 1) the transmitter and the antenna, and 2) the antenna and the receiver, in response to a control signal. The controller generates the control signal to change the presented impedance difference in response to a signal parameter.

Abstract: A time division duplex (TDD) single sideband (SSB) transceiver includes a transmitter adapted to input an analog audio signal, sample the analog audio signal, and to output an SSB frequency shift keyed (FSK) signal corresponding to the analog audio signal, the SSB FSK signal including analog information. A receiver is adapted to switch between receiving one of an upper sideband and a lower sideband of an external SSB signal.

Abstract: In code division multiple access (CDMA) mobile communications system in handing-over allowing wireless mobile station to be connected to a plurality of base stations simultaneously the mobile station uses transmission power control (TPC) information received from each base station to control transmission power and when the information is not reliable (SP1) a link's quality (a signal to interference ratio (SIR)) is compared with a threshold and until the quality exceeds the threshold and the information recovers in reliability the transmission power is controlled to have a fixed level to present the transmission power from attaining maximal transmission power (SP2).

Abstract: According to the invention, a transmitter antenna selector switch 109 or a receiver antenna selector switch 111 is respectively connected between the first antenna 101a and the second antenna 101b and the transmitter 103 or the receiver 105. Transmission signals output from the transmitter 103 are supplied to either the first antenna 101a or the second antenna 101b in transmission, while reception signals are received from either the first antenna 101a or the second antenna 101b via the receiver antenna selector switch 111 in reception.

Abstract: An apparatus for switching a matching circuit in a mobile communication terminal includes a PIN diode connected in parallel to an RF signal input and output line to be turned on and off to connect and disconnect an impedance matching-element to the RF signal input and output line in accordance with a frequency band switching-signal, and a bias circuit for generating a bias voltage applied to the PIN diode in accordance with the frequency band switching-signal, thereby shifting an amplitude of an RF signal to a positive side at an off-time of the PIN diode.

Abstract: A high-frequency module prevents distortion in first and second diodes of a high-frequency switch in a communication system which is not selected without providing a negative power source, and a communication apparatus includes such a high-frequency module. The high-frequency module includes a diplexer having inductors and capacitors, and high-frequency switches including first and second diodes, transmission lines, inductors, and capacitors.

Abstract: The present invention, illustrated in various embodiments, provides mechanisms for transferring data in wireless communications systems. In one exemplary embodiment, the data is transferred in an access point (AP) used in a wireless local area network (WLAN), which comprises a wireless communication system connected to a local area network (LAN). The access point includes a baseband chip capable of adapting various radio frequency (RF) units. Each RF unit in turns includes a plurality of RF sub units connected in a daisy-chain manner. Each RF sub unit is also connected to at least one antenna. The access point thus includes a number of antennas that, together with the RF units and the baseband chip, form a smart antenna. In a receiving mode, the data received from the smart antenna travels through the RF sub units in each RF unit, and the data from the RF units travels to the baseband chip.

Abstract: A quadrature tranceiver has a transmitter, a receiver, and a common local oscillator. With the transmitter switched off and the receiver switched on, a DC-error in the receiver is nulled in servo loops in in-phase and a quadrature receiver paths. After settling, the servo loops provide output values that are freed of the DC-error. DC-nulling output values are then sampled and stored. After sampling, the servo loops are opened. Thereafter, the transmitter is switched on while inputting a fixed signal to the transmitter, and DC-signals injected into in-phase and quadrature paths of the transmitter are adjusted until the opened servo loops provide the same output signal as obtained at the end of the DC-nulling. Corresponding values of the injected DC-signals are then stored as transmitter calibration values.

Abstract: A dual band transmitter (1) including: a lower band power amplifier (2) and a higher band power amplifier (3), a lower band transmit path (4) between the output of the lower band power amplifier (2) and a combining means (8); and a higher band transmit path (5); between the output of the higher band power amplifier (3) and the combining means (8). A surface mounted device includes a stub (6) having a first (61) and a second (62) end, the first end of the stub (6) being connected to the higher band transmit path (5) and the second end of the stub (6) being coupled to a switch. The second (62) end of the stub (6) is substantially closed or opened, in dependence upon the state of the switch, so that, in use, spurious harmonics are prevented from being generated in, and transmitted from, the transmitter (1).

Abstract: A loop antenna is constructed by bending a linear conductor so that it forms concavo-convex portions within an antenna plane.

Abstract: A radio frequency (RF) integrated circuit (IC) includes a local oscillation module, analog radio receiver, analog radio transmitter, digital receiver module, digital transmitter module, and digital optimization module. The local oscillation module is operably coupled to produce at least one local oscillation. The analog radio receiver is operably coupled to directly convert inbound RF signals into inbound low intermediate frequency signals based on the local oscillation. The digital receiver module is operably coupled to process the inbound low IF signals in accordance with one of a plurality of radio transceiving standards to produce inbound data. The digital transmitter is operably coupled to produce an outbound low intermediate frequency signal by processing outbound data in accordance with the one of the plurality of radio transceiving standards. The analog radio transmitter is operably coupled to directly convert the outbound low IF signals into outbound RF signals based on the local oscillation.

Abstract: A communications device for transmitting RF signals from an external antenna. The device comprises a transceiver that sends signals over a cable to an external active antenna. In one embodiment the signals transmitted over the cable intermediate RF frequency signals. The active antenna receives the intermediate RF signals over the cable and up converts or down converts the respective RF transmit and receive signals. In another embodiment of the invention the signals transmitted over the cable are digital signals. The active antenna is functional to process, and covert the respective RF transmit and receive signals.

Abstract: A multi-band antenna and a notebook computer with a built-in multi-band antenna are disclosed. Since the multi-band antenna is installed at the inner side of a upper and a lower case, it is much favored for a radio communication when a computer is in use by standing up a display device. The multi-band antenna includes at least two transmitting and receiving parts formed with different lengths to fit frequency bands, so that a remote communication of at least two or more bands can be made. The multi-band antenna is positioned between liquid crystal and a side wall of the lower case, and a grounding unit is installed to contact a liquid crystal frame. That is, since the grounding unit is grounded to the liquid crystal frame and the bracket, substantially, the liquid crystal frame and the bracket are wholly grounded to ensure a stable radio frequency communication.

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.

Abstract: A communication system for communicating CDMA and GSM transmit and receive RF information signals through one or more antennas is disclosed. The communication system is comprised of a transmitting unit, a receiving unit, and at least one antenna. The transmitting unit modulates and upconverts a transmit baseband information signal to generate a CDMA transmit RF information signal and a GSM transmit RF information signal. The receiving unit downconverts and demodulates a CDMA receive RF information signal and a GSM receive RF information signal to generate a receive baseband information signal. One or more antennas are coupled to the transmitting unit and receiving unit for transmitting the CDMA transmit RF information signal and the GSM transmit RF information signal, and receiving the CDMA receive RF information signal and the GSM receive RF information signal.

Abstract: The present invention relates to a method and system using dynamic beam forming for wireless communication signals in a wireless network. Base stations and/or UEs are provided with antenna systems having a range of beam forming selections. Relative base station and UE locations are one type of criteria used to make beam forming decisions.

Abstract: An antenna system includes a substrate, a ground on the substrate, a first radiator having a helical shape near a side of the substrate and having a central axis substantially in parallel to a side of the ground, and a high frequency circuit electrically connected to a part of the first radiator. In the antenna system, ground-induced degradation of antenna gain can be reduced, and matching can be performed at an operating frequency through adjustment of a winding of the first radiator. Consequently, the radiation gain of the antenna system can be improved without an antenna matching circuit.

Abstract: An antenna circuit configured for use in a radio frequency data communications device has an antenna constructed and arranged to transfer electromagnetic waves, the electromagnetic waves corresponding to a signal carried by the antenna and generated from a signal source. A Schottky diode is electrically coupled in serial relation with the antenna, and in operation the signal is applied serially across the antenna and the diode in direct relation with electromagnetic waves transferred by the antenna. A bias current supply is also electrically coupled to the Schottky diode and is configurable to deliver a desired bias current across the current. The diode is responsive to the bias current to realize a desired diode impedance such that a desired impedance match/mis-match is provided between impedance of the diode and impedance of the antenna when the signal is applied across the antenna circuit, which selectively tunes the antenna circuit by imparting a desired power transfer therein.

Abstract: A radio frequency (RF) transceiver includes a transmit chain that transmits a transmit signal to an antenna and a receive chain that generates a receive signal from the antenna, wherein the receive chain includes a duplexer and the transmit chain is free of a duplexer. By removing the duplexer from the transmit chain, power losses incurred by the duplexer may be reduced and preferably eliminated from the transmit chain. More specifically, an RF transceiver includes a circulator having first, second and third circulator ports, that circulates power from the first circulator port to the second circulator port, to the third circulator port and then to the first circulator port. An amplifier is coupled to the first circulator port and amplifies a transmit signal. An antenna is coupled to the second circulator port. A duplexer is coupled to the third circulator port and generates a receive signal.

Abstract: A diplexer capable of passing signals of a high frequency band without being attenuated over a wide frequency band, and a high-frequency switch using the diplexer are provided. The diplexer includes a low-pass filter 82 having a parallel resonant circuit formed by a first capacitor C1 and a first inductor L1 and a serial resonant circuit formed by a second capacitor C2 and a second inductor L2. With this structure, two attenuation poles are provided in the low-pass filter 82. Thus, a passband of a high-pass filter 83 can be widened.

Abstract: A switching circuit connects transceivers for different frequencies alternatively to a common antenna. The circuit including a plurality of sets, each including a plurality of PIN diodes connected in series, and the PIN diodes in a set may be activated by a DC current, which DC current is led through a bias resistor, creating a bias voltage. This bias voltage is used for reverse biasing the PIN diodes in another set, thus eliminating quiescent PIN diodes therein from creating spurious signals. The circuit is particularly suited for cellular mobile telephones using two frequency bands.

Abstract: Antenna switching circuitry in a multi-transceiver mobile terminal 10, which features a first switching unit (SW1) which controllably couples a first transceiver port (P1) to either a first antenna port (PA1) or a second antenna port (PA2); and a second switching unit (SW2) which controllably couples the second antenna port (PA2) to either the first transceiver port (P1), through the first switching unit (SW1), or to an input/output port (PI/O) of a second transceiver (12).

Abstract: A high gain built-in antenna for a radio communication terminal with less influence from the human body. This built-in antenna for a radio communication terminal includes bar-shaped second passive element 392 facing antenna elements making up dipole antenna 321. The distance between this second passive element 392 and the antenna elements making up dipole antenna 321 is appropriately set in such a way as to widen the band of the input impedance characteristic by changing mutual impedance between second passive element 392 and the antenna elements making up dipole antenna 321.

Abstract: A method and device for using a single antenna for simultaneously receiving radio frequency signals in a first radio frequency band and radio signals in a second radio frequency band different from the first radio frequency band.

Abstract: Techniques are described for space-time block coding for single-carrier block transmissions over frequency selective multipath fading channels. Techniques are described that achieve a maximum diversity of order NtNr (L+1) in rich scattering environments, where Nt (Nr) is the number of transmit (receive) antennas, and L is the order of the finite impulse response (FIR) channels. The techniques may include parsing a stream of information-bearing symbols to form blocks of K symbols, preceding the symbols to form blocks having J symbols, and collecting consecutive Ns blocks. The techniques may further include applying a permutation matrix to the Ns blocks, generating a space-time block coded matrix having Nt rows that are communicated through a wireless communication medium. The receiver complexity is comparable to single antenna transmissions, and the exact Viterbi's algorithm can be applied for maximum-likelihood (ML) optimal decoding.

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 duplex radio transceiver, coupled to baseband circuitry and to an antenna, includes a receive chain, a transmit chain and a duplexer. The transmit chain includes filter components that attenuate signals originating from the transmit chain in a receive frequency band by a stop-band attenuation that is approximately equal to or greater than the stop-band attenuation of the duplexer in the receive band. Similarly, the receive chain includes filter components filter components that attenuate signals in a transmit frequency band by a stop-band attenuation that is approximately equal to or greater than the stop-band attenuation of the duplexer in the transmit band. A bias control circuit senses a power level associated with radio signals in the transmit chain and adjusts an amplifier in the receive chain responsive to the power level.

Abstract: A method and device for using a single antenna for simultaneously receiving radio frequency signals in a first radio frequency band and radio signals in a second radio frequency band different from the first radio frequency band.

Abstract: A tunable resonant system includes an electric element, and a core having a controllable parameter that determines the resonant frequency of the system. In order to tune the resonant system to a desired frequency, a low power, narrowband signal is applied at a selected frequency to the electric element. The reflected or transmitted power is measured and the value of the controllable parameter adjusted to vary the resonant frequency of the system in a closed loop until the reflected power is at a minimum.

Abstract: A base station having N transmission antennas (15) broadcasts M beacon signals (CPICH0, CPICH1), with 1<M<N. Each beacon signal is associated with a distribution vector (a, b) with N components and is applied to each of the antennas after weighting by a component of this vector. A mobile terminal in communication with the base station evaluates the reception of the M beacon signals so as to determine feedback data communicated to the base station. The latter causes the distribution vectors associated with the M beacons to vary over time, and processes the feedback data successively received so as to determine a respective weighting coefficient (w0-w3) for each of the N antennas relative to the mobile terminal. A transmitted dedicated radio signal destined for the mobile terminal is applied to each of the N transmission antennas after weighting by the coefficient determined for this antenna.