3278 results about "Transposer" patented technology

In a multiuser Multiple Input Multiple Output (MIMO) radio communication system, a transmitter receives channel quality information transmitted from receivers, schedules resource for the receivers within a corresponding scheduling epoch based on the received channel quality information. Thereafter, the transmitter pre-codes signals to be transmitted to the resource-scheduled receivers in a predetermined coding method before transmission, thereby maximizing system transmission efficiency.

A method includes broadcasting, at a transmitter, messages comprising antenna configuration, antenna spacing and a number of antenna of the transmitter and reference signals; generating, at a receiver, a codebook comprising a plurality of antenna beams based on the broadcasted messages; receiving, at the receiver, the broadcasted reference signals; selecting, at the receiver, an antenna beam among the plurality of antenna beams within the codebook in dependence upon a predetermined performance criteria of a data communication system and in dependence upon the broadcasted reference signals; feedbacking to the transmitter, at the receiver, information comprising the antenna beam selected by the receiver; optimizing, at the transmitter, a beamforming process by utilizing the feedback information from the receiver; transmitting, at the transmitter, data signals by utilizing the optimized beamforming process; and receiving and processing, at the receiver, the data signals in dependence upon the selected antenna beams within the codebook.

A WCDMA system includes a Base Station (BS) transmitter, or forward transmitter and a pilot channel that transmits control signals between the BS and a Mobile Station (MS) to reconfigure their transmitter/receiver. Reconfiguration is performed according to the prediction of the channel attenuation and the threshold set at the BS or MS based on its channel power probability density function separated into three distinct equal probable regions. In one embodiment, Seamless Rate Change (SRC)/Transmitter Power Control (TPC) logic uses the predicted channel attenuation to signal both the transmitter and the receiver in a channel to reconfigure their transmit power level according to the power density function (pdf) of the channel power and threshold level. A transmission rate is reduced when the power level is below the threshold and increased when the channel power is above threshold. The pilot channel is used to signal the mobile station and the base station.

A method and apparatus for supporting a priority transmission of broadcasting data in a transmitter of a digital broadcasting system. A determination is made as to whether a priority transmission of one broadcasting service to be provided is supported. If the service supports the priority transmission, a plurality of subchannels to be transmitted for the service are set and a priority of the data to be mapped to the plurality of subchannels is set. The data of the broadcasting service is mapped to the plurality of subchannels according to the priority. Data streams mapped to the plurality of subchannels are encoded in different encoders and the encoded data streams are transmitted.

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.

The invention provides a novel method for preparing a wireless environment for location determination of a wireless mobile unit, and for location determination of a wireless mobile unit. In preparing the physical environment, the invention utilizes novel techniques, including novel techniques to place transmitters, the removal of outlying data in the creation of reference RF fingerprints, and algorithms to obtain accurate reference RF fingerprints. In determining the location of a wireless mobile unit, the invention utilizes novel techniques, including novel techniques to select transmitters, the removal of outlying data in the creation of reference RF fingerprints, and algorithms to obtain accurate reference RF fingerprints.

A method for a data transmission with ARQ protocol using multicast groups such as GSM, GPRS or UMTS in a mobile communication system is described. Data is transmitted in data blocks (PDU) from a transmitter (T) to a plurality of receivers (R1-RM), said data blocks (PDU) being identifiable by an identification (e.g. a sequence number). The receivers (R1-RM) send status indications to the transmitter (T) whether a data block (PDU) is correctly received. The transmitter (T) is adapted to perform retransmissions according to the status indications and has a transmission window comprising the transmission status for the data blocks (PDU) according to their identification. In the method, a synchronization to the transmitter (T) is performed for at least one first of said receivers (Ri), wherein a range of identifications of transmitted data block (PDU) is selected in said synchronization. The transmitter (T) deletes the transmission status for the selected range of identifications from the transmitter window and the first receiver (Ri) stops sending status indications for the data blocks (PDU) corresponding to the selected range of identifications. In addition, a transmitter and a computer program implementing the method are described. As an example the transmitter can be a RNC extending the RLC and MAC-HSPDA protocols standardized by 3GPP for obtaining efficient and reliable point-to-multipoint radio links.

A transmitter for broadcasting data in a broadcasting system that improves the decoding quality, if needed, comprises a data input, and an encoder for error correction code encoding the input data words into codewords, a codeword comprising a basic codeword portion and an auxiliary codeword portion, wherein said encoder is adapted for generating said basic codeword portion from an input data word according to a first code and for generating said auxiliary codeword portion from an input data word according to a second code, said basic codeword portion being provided for regular decoding and said auxiliary codeword portion being provided as incremental redundancy if regular decoding of the codeword by use of the basic codeword portion is erroneous. Further, the transmitter comprises a data mapper for mapping the codewords onto frames of a transmitter output data stream, and a transmitter unit for transmitting said transmitter output data stream.

The present invention provides a digital (computational) branch calibrator which uses a feedback signal sensed from an RF transmit signal path following the combining stage of LINC circuitry of a transmitter to compensate for gain and phase imbalances occurring between branch fragment signals leading to the combiner. The calibrator feeds a quiet (zero) base band signal through the transmit path during the calibration sequence (i.e. a period when data is not transmitted) and adjusts the phase and gain of the phasor fragment signals input thereto by driving the sensed output power to zero. The calibration is performed by alternating phase and gain adjustments with predetermined (programmable) and multiple update parameters stages (speeds). A baseband modulation is preferably used to distinguish false leakage (e.g. due to local oscillator, LO, feed through and DC offset in the base band Tx) from imbalance leakage.

A system for digitally linearizing the nonlinear behaviour of RF high efficiency amplifiers employing baseband predistortion techniques is disclosed. The system provides additive or multiplicative predistortion of the digital quadrature (I/Q) input signal in order to minimize distortion at the output of the amplifier. The predistorter uses a discrete-time polynomial kernel to model the inverse transfer characteristic of the amplifier, providing separate and simultaneous compensation for nonlinear static distortion, linear dynamic distortion and nonlinear dynamic effects including reactive electrical memory effects. Compensation for higher order reactive and thermal memory effects is embedded in the nonlinear dynamic compensation operation of the predistorter in an IIR filter bank. A predistortion controller periodically monitors the output of the amplifier and compares it to the quadrature input signal to compute estimates of the residual output distortion of the amplifier. Output distortion estimates are used to adaptively compute the values of the parameters of the predistorter in response to changes in the amplifier's operating conditions (temperature drifts, changes in modulation input bandwidth, variations in drive level, aging, etc). The predistortion parameter values computed by the predistortion controller are stored in non-volatile memory and used in the polynomial digital predistorter. The digital predistortion system of the invention may provide broadband linearization of highly nonlinear and highly efficient RF amplification circuits including, but not limited to, dynamic load modulation amplifiers.

A method and apparatus for providing a universal transmitter that can detect and emulate a transmission signal of a transmitter, the transmission signal having a corresponding transmission frequency and a corresponding modulation pattern. The universal transmitter comprises: a detection circuit that detects a frequency and a modulation pattern of a transmitted signal of a separate transmitter and a memory. A processor coupled to the detection circuit and the memory, stores a frequency value representative of the detected frequency and a plurality of value representative of the detected modulation pattern, in the memory. A transmitting circuit coupled to the processor, is operable to transmit an output signal having the frequency and the modulation pattern of the transmission signal.

A transmitter/receiver combination system and a transmission signal canceling method for use in a wireless communication system using a single common antenna are provided. The system includes a circulator for receiving an original transmission signal from the transmitter, transmitting the received transmission signal to an antenna without a signal loss, and transmitting a reception signal received from the antenna to other ends without a signal loss, and a transmission signal canceller for dividing the transmission signal input in an attenuated form as much as a predetermined magnitude via the circulator together with the reception signal into two paths, producing two is phase inverted transmission signals with the same magnitude and delay time as those of the original transmission signal, and recombining the produced two transmission signals with each other, to thereby canceling the transmission signal and transmitting only the reception signal to the receiver.

A method for distributed spectrum management of digital communication systems having a plurality of communication lines on which signals are transmitted and received by respective users, the method comprising the steps of: collecting information about line, signal and interference characteristics of a plurality of the communication lines from a plurality of sources; determining the line, signal and interference characteristics of a plurality of the communication lines; varying power allocation of particular plurality of the communication lines between respective transmitter and receiver taking into consideration the determined line, signal and interference characteristics of a plurality of the communication lines and consideration of a noise weight of a plurality of the communication lines to enable a minimum power on a plurality of the communication lines and to allow required effective data-rates for each of said respective users to be satisfied.

Methods and apparatus for synchronizing Wireless Local Area Network (WLAN) communication within a multi-mode radio. A multi-mode radio can support communication with a WLAN and at least one other wireless communication system. The multiple systems can be distinct and asynchronous. Transmitting, or attempting to transmit, over a WLAN communication link can result in interference that degrades the sensitivity of a receiver in another communication system, or that interferes with a transmission in another communication system. The WLAN transmissions can be synchronized to operation in another communication system by generating a signal that can be coupled to a collision avoidance system in the WLAN transmitter. The signal can operate to cause the WLAN transmitter to reschedule the transmission to another time such that the resources of the multi-mode radio are conserved and the WLAN interference is minimized.

The present invention relates to a monitoring system that observes the power and optical frequency of a frequency-modulated optical signal, which is utilized in the communication network employing the WDM (wavelength division multiplexing) method. The monitoring system comprises demultiplex means for demultiplexing the frequency-modulated optical signal outputted from a transmitter including frequency-modulation means, photo-detection means for converting the output of demultiplex means into an electrical signal, and extraction means for extracting the power and optical frequency of an optical signal by measuring the magnitude of an amplitude-modulated tone.

A system for a baseband near field magnetic stripe data transmitter includes a mobile phone and a magnetic stripe transmission (MST) device. The mobile phone transmits a stream of pulses including magnetic stripe data of a payment card. The magnetic stripe transmission (MST) device includes a wave shaper, a driver and an induction device. The MST device receives the stream of pulses from the mobile phone, shapes and amplifies the received stream of pulses and generates and emits high energy magnetic pulses including the magnetic stripe data. The emitted high energy magnetic pulses are picked up remotely by a magnetic read head. The MST device shapes the stream of pulses to compensate for shielding, eddy current losses and limited inductance value of the magnetic read head.

A transponder system is provided which presents a light weight portable or mobile system for localization of movable objects, e.g., for surveillance of valuable transports and the like. The small unit constituting the transponder contains a receiver (1) of paging type, a decoder (2), a logic unit (3), a transmitter portion (10), a built-in antenna and power supply (11). The system is controllable by an existing tested radio system for paging. One advantage of utilizing an already existing paging system is that functionality is well tested and a general covering range is obtained. In addition, costs for building up and operation of a paging system are eliminated. Control information being sent to the transponder includes a number of symbols defining a certain basic function for the built-in marker transmitter (10) and symbols which constitute control code and control data for the specific function. Consequently at least the frequency, transmit power and transmitting sequences of the marker transmitter are controllable.