Abstract: A low-cost diversity antenna switching system and method is realized by controlling bias voltages on PIN diodes. By increasing the reverse bias voltage impressed upon a PIN diode, an RF signal impressed upon the diode is increasingly attenuated. As the PIN diode is forward biased to conduct in the forward direction, RF attenuation decreases. Two or more PIN diodes are used to increasingly attenuate signals from one antenna as attenuation of signals from another antenna is gradually decreased. The progression of the bias voltages is accomplished using a microprocessor that monitors a received signal strength indicator (RSSI) signal from a radio receiver. The RSSI is used to control which of two antennas are coupled into the receiver by predicting a signal fade.

Abstract: A wireless information device (30) receives and processes a message (32) within a wireless information communication system (10). The wireless information device (30) includes an antenna system (62), a radio frequency switch (80), a controller (84) and a display (60). The antenna system has a plurality of antennas for receiving the message (32). The radio frequency switch (80) activates a first antenna (64) of the plurality of antennas as an active antenna (116) in response to an antenna control signal (98) sent from the controller (84). The antenna control signal (98) is generated by the controller (84) in response to the determination of the display orientation of the display (60).

Abstract: An apparatus for modifying a radio frequency signal includes a mixer core, an input circuit and an interface circuit. The mixer core receives a first signal having a first frequency and a second signal having a second frequency, and outputs a third signal which is a function of the first and second signals. The input circuit sets a predetermined bias current, receives a radio frequency (RF) signal and inputs the RF signal into the mixer core. The interface circuit is interposed between the mixer core and the input circuit. The interface circuit receives the bias current and input it to the mixer core. In one embodiment, the input circuit includes a transistor and the interface circuit includes a transformer.

Abstract: Briefly, in accordance with an embodiment of the invention, an apparatus and method to provide antenna diversity to reduce multipath effects is provided. The apparatus may include a primary antenna and a secondary antenna, wherein the antenna gain of the secondary antenna is greater than the antenna gain of the primary antenna. The method may include selectively switching between either a primary antenna or a diversity antenna to receive signals, wherein a gain of the primary antenna is less than a gain of the diversity antenna.

Abstract: An automatic function control of an antenna unit of a vehicle-mounted toll unit of an electronic toll system including a position detection system is disclosed. The toll unit includes a reception unit linked with the antenna unit and the antenna unit is adapted to receive position detection signals. At least one control signal that interacts with the antenna unit is produced and supplied to the toll unit, and the function of the antenna unit is checked by use of the control signal.

Abstract: A multi-band antenna switch circuit including a diplexer connected to an antenna terminal for demultiplexing signals of different passing bands, a first and a second switch circuit for switching a high frequency signal and a low frequency signal demultiplexed by the diplexer to a plurality of transmission/reception terminals, a first and a second low pass filter connected to a transmission path between the diplexer and the transmission terminal or between the first and the second switch circuit and the transmission terminal, and a notch filter provided between the diplexer and the first switch circuit or between the diplexer and the second switch circuit.

Abstract: A base station in a communication network which has a number of receiver or transmitter circuits (TRX) and a number of splitters (SP1, . . . SP6) is provided with switchable divider circuitry, if the number of receiver or transmitter circuits (TRX) is other than 2n(n=2, 3, 4, . . . ). The divider circuit has at least an input, preferably two inputs (IN-A, IN-B), an attenuation member, preferably two members (AT1, AT2) and a divider element (DE), preferable three elements (DE1, DE2, DE3) and is connected parallel to a respective splitter (SP) so as to offer further splitter outputs for being connected to the inputs of remaining receivers or transmitter circuits (TRX) other than 2n.

Abstract: A radio receiver system having a plurality of receiving antennas and a plurality of receivers is described in which antenna signals of a multiplicity of the plurality of receiving antennas are fed to each of the plurality of receivers. The plurality of receiving antennas may be interconnected to the plurality of receivers more flexibly as a function of the desired reception strategy. In addition, the functionality of the entire system may also be maintained in the event of a defect or failure of one or more receiving antennas.

Abstract: A method and apparatus for collecting data downhole in a well bore, even during drilling operations, are disclosed. The apparatus generally comprises an antenna and some associated electronic circuitry. The antenna includes a plurality of arrayed transceiver elements and the electronic circuitry steers transmission or reception through the antenna by controlling the application of power to the array elements. In operation, a transceiver unit containing such an antenna is positioned proximate a remote sensor placed into a formation. An electromagnetic signal is then steered to communicate with the remote sensor over a wireless link.

Abstract: A method includes generating a received signal vector from a signal received over a channel. The received signal vector includes a plurality of symbols encoded in accordance with a block code having a structure. A channel matrix estimated for the channel is transformed based on the structure of the block code to generate an aggregate channel matrix. The symbols are processed using the aggregate channel matrix. A system includes a front end unit configured to generate the received signal vector, a channel estimation unit configured to estimate the channel matrix, and a processing unit configured to generate the aggregate channel matrix and process the symbols using the aggregate channel matrix.

Abstract: Provided is an apparatus adapted to transmit a first channel on at least two adjacent fixed beams of a plurality of fixed beams defining a coverage area, with each pair of adjacent fixed beams of the plurality of fixed beams partially overlapping and having substantially orthogonal polarizations. The apparatus has a respective transmitter adapted to transmit on each of the plurality of fixed beams a respective unique composite signal, each composite signal containing said first channel and a respective unique traffic channel.

Abstract: Briefly, a method and apparatus to detect and acquire a frame within a transmission are provided. The apparatus may be coupled to at least two antennas and may include a frame acquisition module to detect and acquire the frame received within a transmission by one of the antennas.

Abstract: A radio system includes a base station and a remote station. The base station includes a space-time encoder, an antenna system, a transmitter, a base station receiver, and a power management controller. The space-time encoder encodes a stream of symbols into first and second space-time coded signals, and the transmitter transmits the first and second space-time coded signals at respective first and second initial transmit powers from the antenna system so as to form respective first and second radiation patterns. The base station receiver receives power coefficient indicator information from the remote station, and the power management controller determines first and second adjusted transmit powers based on the respective first and second initial transmit powers and the power coefficient indicator information. In an alternative embodiment, a transmit station of a radio system includes a circuit to determine an angular power spectrum, a space-time encoder, and a transmitter.

Abstract: An equal gain composite beamforming technique which constrains that the power of the signal output by each antenna is the same, and is equal to the total power of the transmit signal divided by the number N of transmit antennas from which the signal is to be transmitted. By reducing output power requirements for each power amplifier, the silicon area of the power amplifiers are reduced by as much as N times (where N is equal to the number of transmit antennas) relative to a non-equal gain CBF.

Abstract: A method and an arrangement are provided for timing a change of diversity weights in a radio connection between a base station and a terminal. A response timing mode is selected from a number of predefined response timing modes. The terminal is informed about the selected response timing mode. An initiation is received from the terminal and it is responded to the initiation by changing certain diversity weights so that the exact moment of time for effecting the change is determined by the selected response timing mode.

Abstract: A wireless communication system base station uses a dual-polarized antenna array to receive two signal groups having orthogonal polarizations. In a preferred embodiment a first signal group is received using a first sub-array of odd-numbered antenna elements, while a second signal group is received using a second sub-array of even-numbered antenna elements. Dipoles within the odd-numbered elements are selected so that they have a common polarization orthogonal to the dipoles selected in the even-numbered elements. The two signal groups thus have orthogonal polarizations. Base station signal processing hardware performs separate spatial channel estimation for these two groups, and uses the polarization diversity to improve performance in both the uplink and downlink. The use of polarization diversity allows the physical dimensions of the antenna array to be kept to a minimum.

Abstract: The per antenna capacity of each of the transmitter antennas in a MIMO system are individually determined from measurable information at the receiver end. Specifically, the channel capacity for each individual transmitter antenna is calculated at the receiver end as a function of measurable channel coefficients (also known as channel state information), the measurable average signal-to-noise ratio, and the number of transmitter antennas. Once the per antenna capacity of each transmitter antenna is individually determined at the receiver end, the maximum transmission rate for each data stream transmitted by each transmitter antenna is determined from that individual capacity either at the receiver end and fed back to the transmitter end, or is determined at the transmitter end from the individual transmitter antenna capacities that are fed back by the receiver end to the transmitter end. A modulation scheme that supports each maximum transmission rate is then determined based on some defined criteria.

Abstract: A method for receiving radio frequency signals transmitted by a radio signal transmitter with an access point includes using a plurality of antennas to receive radio signals transmitted by the radio signal transmitter and from other directions via reflection during a predetermined period of time, and using the processor to sum up radio signals received by the plurality of antennas during the predetermined period of time to obtain a summation of radio signals transmitted directly from the radio signal transmitter to the access point and of radio signals transmitted via reflection from the radio signal transmitter to the access point.

Abstract: When the communication rate of a transmission signal is not less than a predetermined value, antenna switching section 104 outputs the transmission signal to antenna 102 for vertical polarization, while when the communication rate of a transmission signal is less than the predetermined value, outputting the transmission signal to antenna 103 for horizontal polarization. Antenna 103 transmits the transmission signal in horizontal polarization. Antenna 202 receives radio signals principally in vertical polarization. Antenna 203 receives radio signals principally in horizontal polarization. When the communication rate is not less than a predetermined value, antenna switching section 204 outputs a signal received in antenna 202 to receiving section 206, while when the communication rate is less than the predetermined value, outputting a signal received in antenna 203 to receiving section 206.

Abstract: A synchronization system within a dual antenna receiver employs two timing recovery loops each coupled to a different antenna input. The timing error computed within each timing recovery loop is differentiated by a high pass filter and compared to a predefined threshold indicating convergence. Both sampling rates are then synchronized utilizing the timing error from whichever loop converges first. If synchronization lock for the selected loop is lost, the other loop is selected to provide timing error to both loops.

Abstract: An antenna structure which has a platform defining at least six sectors having a vertex contained substantially within the platform. At least six dual polarized antennas are positioned on the platform for transmitting and receiving signals substantially in each of the at least six sectors, respectively.

Abstract: A composite beamforming technique is provided wherein a first communication device has a plurality of antennas and the second communication has a plurality of antennas. When the first communication device transmits to the second communication device, the transmit signal is multiplied by a transmit weight vector for transmission by each the plurality of antennas and the transmit signals are received by the plurality of antennas at the second communication device. The second communication device determines the best receive weight vector for the its antennas, and from that vector, derives a suitable transmit weight vector for transmission on the plurality of antennas back to the first communication device. Several techniques are provided to determine the optimum transmit weight vector and receive weight vector for communication between the first and second communication devices so that there is effectively joint or composite beamforming between the communication devices.

Abstract: A transmitting unit of a portable telephone apparatus transmits radio signals by using at least two antennas and simultaneously energizing those antennas with a predetermined amplitude ratio and a predetermined phase difference so that the direction of the main beam of a radiation pattern has a direction substantially opposite to that of the audio radiating direction from a speaker, and so that the mean effective gain is larger than that of when a single antenna is energized. The above energization of at least two antennas is formed only for transmission of telephone speech. A receiving unit of the portable telephone apparatus receives radio signals by using at least two antennas, and selectively receives, by the diversity receiving system, the radio signal having the highest level of those radio signals received by those antennas.

Abstract: A wireless communication network which includes an antenna array for receiving and transmitting signals to and from remote users which is capable of adapting to widely varying traffic levels. Different antenna elements can be turned on during high user periods and off when there are fewer users. Also, beam width can be varied, with fewer antennas having wide beams in use when traffic levels are low and more antennas with narrow beams when traffic is high. Generally, the maximum capability uses 180 antenna elements with beam widths of about 2° to cover a full 360°. This network can act as either a circuit switched network or a packet switched network, as desired.

Abstract: A MIMO radio transceiver to support processing of multiple signals for simultaneous transmission via corresponding ones of a plurality of antennas and to support receive processing of multiple signals detected by corresponding ones of the plurality of antennas. The radio transceiver provides, on a single semiconductor integrated circuit, a receiver circuit or path for each of a plurality of antennas and a transmit circuit or path for each of the plurality of antennas. Each receiver circuit downconverts the RF signal detected by its associated antenna to a baseband signal. Similarly, each transmit path upconverts a baseband signal to be transmitted by an assigned antenna.

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: A vehicle navigational receiver module includes a first planar antenna for receiving navigational radio signals, a signal processing circuit that is connected to the antenna, as well as a ground plane. In addition, a second planar antenna for receiving a telematic radio signal is arranged so as to at least partially overlap the first planar antenna and is connected to a second signal processing circuit.

Abstract: An interference protection system includes a receiving section for receiving an electromagnetic signal, a detector for detecting a jamming signal, and a control system for orienting a changeable null direction of an antenna system to reduce interference in a receiver from the jamming signal.

Abstract: A dual-mode Wireless Local Area Network (WLAN) module installed in an electronic device (600) for wireless communication with other electronic devices includes an RF front-end unit (30), two dual-band antennas (40) coupled to the RF front-end unit, a dual-band radio frequency integrated circuit (RFIC) (20) coupled to the RF front-end unit, a dual-band base-band integrated circuit (BBIC) (10) coupled to the RFIC, and an interface unit coupled to both the BBIC and a computer (600). The RF front-end consists of transmitting and receiving paths. The RF front-end unit has antenna diversity control switching circuits (31, 33) for selecting an appropriate antenna and switching circuits (32, 34, 35, 36) for controlling ON/OFF states of transmitting/receiving paths of the RF front-end unit.

Abstract: A digital camera having a wideband RF transceiver, includes: a graphic user interface for displaying a camera control menu, the graphic user interface having a normal viewing axis; camera grips located on opposite sides of the camera body for holding the camera to operate the transceiver while viewing the graphic user interface; and a directional antenna arranged with respect to the camera to point away from a user of the camera and having a 90±10 degree vertical beam width centered on the horizon ±20 degrees, and a 180±20 degree horizontal beam width when the camera is held by the grips for normal viewing of the graphic user interface while operating the transceiver.

Abstract: A surface-acoustic-wave filter has a piezoelectric substrate; and a plurality of transversal surface-acoustic-wave (SAW) filters set on the piezoelectric substrate and respectively having at least two inter-digital transducer (IDT) electrodes for transcieving surface acoustic waves, characterized in that periods for surface acoustic waves to propagate from inputs to outputs of the SAW filters differ in the SAW filters and thereby, timings of outputs from the SAW filters are different from each other.

Abstract: A method and apparatus are provided that allows initial beamforming weights to be determined before timing or delay and frequency offset are known. According to one aspect of the present invention, the invention includes receiving a burst from a terminal at a set of spatial diversity antennas, the burst including a known training sequence and storing measurements of the received burst from each spatial diversity antenna corresponding to receive times within a selected analysis window. The invention further includes determining weights for each diversity antenna for at least a portion of the training sequence of the burst before timing for the burst has been determined, applying the determined weights to the stored measurements and determining timing for the burst based on the stored measurements to which the determined weights have been applied.

Abstract: A receiving antenna system includes an antenna unit, a receiver unit, a down converter and a DC power/control supply. The antenna unit includes a parabolic reflector, a feed horn and an orthomode transducer, which are configured to capture, isolate, and output respective first and second polarized RF signals. The receiver unit is coupled to the antenna unit and is configured to amplify the respective RF signals and output a selected one of the respective amplified RF signals in response to a DC control signal. The down converter is coupled to the receiver unit via a transmission line and is configured to further amplify, down convert and output the selected amplified RF signal as an intermediate signal. The DC power/control supply is coupled to the receiver unit via the same transmission and is configured to produce a power/control signal that is transmitted over the same transmission line in which the selected amplified RF signal is transmitted, thereby providing power and control to the receiver unit.

Abstract: Vector orthogonal frequency division multiplexing (VOFDM) receiver correlation matrix processing using factorization. Efficient correlation matrix processing is used to combine multiple signals into a single combined signal. This single combined signal may be viewed as being a beam form soft decision. An efficient square root factorization system and method provides for computational resource savings while, at the same time, providing for greater precision of the overall computational results. By reducing intermediate variable calculation dynamic ranges, the overall calculation becomes more precise. Particularly within fixed-point arithmetic applications, a reduction in dynamic range of the intermediate variable calculations provides for a significant increase in final calculation precision.

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: 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: A radiotelephone system for motor vehicles, having a group antenna system with a plurality of antenna elements, and a mobile radiotelephone with a high-frequency input for receiving radio signals. The group antenna system contains controllable phase and/or amplitude adjusting elements, which are set so that a directed reception with a main receiving direction is available. The controllable phase and/or amplitude adjusting elements are controlled by a processor for tracking the main receiving direction azimuthally in the direction of a fixed station with the help of a tracking signal. Controllable switching-elements for reversing antenna signals for diversity reception are integrated in the signal paths of the group antenna system so that the azimuthal main direction of reception is tracked with a defined tracking by setting a combination of the switching positions of the controllable switching elements.

Abstract: A receiver provides received analog signals to a plurality of channel branches, and on at least one of the channel branches, the frequency of the received analog signals is adjusted independent of the relative positions of the corresponding analog signals in the radio frequency (RF) spectrum. The analog signals on the channel branches are then combined, and the combined analog signals are converted into the digital domain. For example, the receiver comprises at least one antenna(s) which receives radio frequency (RF) analog signals. A channel branch arranger receives the analog RF signals from the antenna(s) and provides the RF analog signals to a plurality of channel branches.

Abstract: The process relates to communication between a mobile receiver fitted with at least two antennas of which one antenna is less sensitive, an internal transmitter and an external transmitter respectively inside and outside a vehicle.

Abstract: The invention provides a mobile communication apparatus of the diversity system including a plurality of transmitter-receivers of different transmission/reception systems wherein a drop of the antenna reception sensitivity of one system by an output from the antenna of the other system is minimized and the synchronism keeping accuracy is augmented and besides unnecessary dissipation of power is prevented.

Abstract: A satellite receiver is switchable between an operating mode wherein the receiver is capable of generating an output signal using received signals from one or a plurality of satellites, aid another operating mode wherein the receiver generates an output signal using signals received from only one satellite. The former operating mode is useful when the receiver is operating in a mobile environment. The latter operating mode is useful when the receiver is operating in a fixed environment. The receiver is configured to detect the mode in which it is operating. The receiver comprises at least two recevier arms for processing a broadcast signal from a selected one of two satellites. The receiver disables one of the arms when the receiver is stationary.

Abstract: Disclosed is a signal path searching method in a mobile communication system provided with a plurality of array antenna elements. According to the method and apparatus, the path search is performed using a signal of a chip level or a signal of a symbol level, and it is decided whether to first perform a temporal process or a spatial process according to the level.

Abstract: To provide an adaptive array antenna directivity control system that can select a path optimum for communication depending on the state of communication with a mobile station, and improve an interference removing effect.

Abstract: A path search processing section 110 of a searcher 108 performs despreading processing for a signal that has undergone AAA reception by an MF 110a. A power addition circuit 110c adds power of a signal in which coherent addition of a despread signal has been performed, and outputs the result to a delay profile circuit 110d and also to threshold value decision circuit 111. Outputs from respective threshold value decision circuits 111 are output to a combining circuit 112. A power combination value combined by the combining circuit 112 is output to a delay profile circuit 113, and a delay profile is created based on this power combination value. A finger assignment circuit 114 finds despreading timing for AAA reception weight control from the delay profile.

Abstract: Systems and methods for optimizing performance of personal area network (PAN) systems that use electric fields as communication media between PAN transmitters carried by people and PAN receivers mounted on computers to which selective access is sought to be established. Multiple PAN receiver antennae are mounted on a keyboard, such that if a person with a PAN transmitter rests her arms on or near the keyboard, sufficient signal from the transmitter is sensed by one or more of the receiver antennae even though some of the signal is shunted away from the receivers through the arms. Also, a driven shield insulates a PAN receiver from nearby metal objects, e.g., a desk on which the PAN receiver is supported. Moreover, a multiple-electrode PAN transmitter reduces the deleterious effects on the signal from the PAN transmitter that can otherwise be caused by, e.g., loose metal coins that are present in a pocket in which the transmitter is carried.

Abstract: A mobile communication apparatus having multiple transmission antennas and multiple reception antennas and a mobile communication method used in the mobile communication apparatus, wherein a base station, which has at least one reception antenna, restores long-term and short-term information determined in consideration of first characteristics in a mobile station, which has at least one transmission antenna, from a feedback signal received from the mobile station, spatially processes dedicated physical channel signals using basis information produced from the restored long-term and short-term information, and transmits the results of addition of the spatially-processed signals to pilot signals to the mobile station, wherein the first characteristics are the characteristics of the downlink channels of the respective transmission and reception antennas.

Abstract: A data transmitting/receiving apparatus and method using an antenna array in a mobile communication system. A Node B measures a transmission status of each transmission antenna, classifies transmission data according to priority, and transmits to a UE high-priority data through a transmission antenna at a relatively good transmission status and low-priority data through a transmission antenna at a relatively poor transmission status.

Abstract: A method of selecting between first and second antennas in a quadrature amplitude modulation receiver having in-phase (I) and quadrature (Q) signal channels for demodulating signals received by the antennas, comprising the steps of imultaneously connecting the first antenna to the I channel to obtain a first output signal having a first amplitude, and the second antenna to the Q channel to obtain a second output signal having a second amplitude; measuring the first and second amplitude to obtain a greater amplitude for one on the antennas; and switching to said of the antennas having the greater amplitude for demodulating the received signals.

Abstract: In this invention, a diversity antenna and dual-band antenna are attached to the display portion of the portable information device. The dual-band antenna is connected to a Bluetooth circuit and wireless LAN 802.11a reception circuit. The diversity antenna is connected to a wireless LAN 802.11a transmission circuit. The Bluetooth circuit is not influenced by the wireless LAN 802.11a transmission system circuit. This invention can provide a compact portable information device.

Abstract: A base station of a radiocommunication system has at least two antennas and can select one of the antennas. It determines if a channel to transmit to at least one mobile station is unidirectional and switches from one antenna to another in accordance with a predetermined random or pseudo-random law if the channel to transmit is unidirectional.