48results about "Depolarization effect reduction" patented technology

An apparatus and method for interference cancellation in wireless mobile stations operating concurrently in two or more wireless modes.

An orthogonal cross-polarization interference compensating device for solving the problem tin which integration contents of an integration circuit are indefinite when a control loop is cut. An orthogonal cross-polarization interference compensator generates a compensation signal for compensating phase noise included in an own polarization signal. A demodulator compensates for orthogonal cross-polarization interference based on the compensation signal for the phase noise included in the own polarization signal. An error detector generates an error signal indicating phase difference between the own polarization signal compensated by the demodulator and a proper own polarization signal. A phase noise phase detector generates a differential signal indicating phase difference between the own polarization signal and other polarization signals based on the compensation signal and the error signal. An integration circuit integrates the differential signal and generates an integration signal. An infinite phase-shifter adjusts the compensation signal based on the integration signal. A control circuit determines whether or not orthogonal cross-polarization interference is present based on the compensation signal adjusted by the infinite phase-shifter, and adjusts the integration value indicated by the integration signal to be a predetermined value when there is no orthogonal cross-polarization interference.

[Object]

A wireless communication system capable of detecting propagation path modification from the outside and compensating for degradation of quality of communication between transmission and reception with respect to the propagation path modification is provided. A wireless communication system includes a transmitter that transmits electromagnetic waves in which a polarization direction rotates according to a signal in which data is loaded on a carrier, and a receiver that receives the electromagnetic waves and demodulates the data, in which the transmitter imparts angle information indicating a polarization direction for transferring the data to the signal, and sets a rotation frequency of the polarization direction to a frequency lower than a frequency of the carrier, and the receiver changes a polarization direction of the received electromagnetic waves, based on the angle information transferred by the electromagnetic waves. The receiver can detect propagation path modification from the outside using the angle information of the polarization direction, and compensate for degradation in quality of communication between transmission and reception by changing the polarization direction of the received electromagnetic waves when the modification is detected.

An exemplary system may comprise a first and second device and a first and second power splitter coupled to a single cable. The first device may be configured to receive a first noise signal of a first polarization, and to adaptively cancel, based on the first noise signal, first noise from the noisy signal associated with an orthogonal polarization. The second device may be configured to receive a second noise signal of a second polarization, and to adaptively cancel second noise from the noisy signal associated with an orthogonal polarization based on the second noise signal. The first power splitter may be configured to receive the first noise signal from the single cable and provide the first noise signal to the first device. The second power splitter may be configured to receive the second noise signal from the single cable and provide the second noise signal to the second device.

An antenna system for receiving an RF signal from a first antenna and a second antenna includes a phase shift circuit. The phase shift circuit shifts a phase of the RF signal from the second antenna by one of a plurality of possible phase shifts to produce a phase shifted signal. A combiner combines the RF signal from the first antenna and the phase shifted signal to produce a combined signal. A comparator circuit compares a signal quality of the combined signal with a minimum threshold value to determine if the signal quality of the combined signal is equal to or greater than the threshold value. The comparator circuit is in communicative control of the phase shift circuit and maintains the phase shift of the RF signal received by the second antenna in response to the signal quality of the combined signal being equal to or greater than the threshold value.

The embodiment of the invention provides a channel state information feedback method. The method comprises: receiving downlink symbols from a base station, wherein the downlink symbols comprise pilot frequency; obtaining a channel matrix according to the pilot frequency included in the downlink symbols; calculating a precoding matrix according to the channel matrix and a basic codebook; generating a CSI according to the precoding matrix; and sending uplink symbols to the base station, wherein the uplink symbols carry CSI. The embodiment of the invention further provides a precoding method, a terminal device and a base station. According to the technical scheme provided by the invention, each group of antennas selects at least one wave beam for weighting merging to construct a new wave beam, and the new wave beam is used to perform weighting of the group of antennas. The constructed network wave beam can more accurately simulate the real environment of the channel so as to improve the precoding accuracy.

An analog beamforming transmitter includes: a plurality of beamforming transmission circuits coupled in parallel between a signal input and an array of antenna ports, wherein the signal input is configured to receive an analog complex-valued communication signal having an in-phase and a quadrature component, wherein each antenna port of the array of antenna ports is configured to provide a dual-polarized antenna signal having a first polarization component and a second polarization component, wherein each beamforming transmission circuit is coupled between the signal input and a respective antenna port of the array of antenna ports, wherein each beamforming transmission circuit comprises a first coefficient input for receiving a first analog complex-valued beamforming coefficient a set offirst analog complex-valued beamforming coefficients and a second coefficient input for receiving a second analog complex-valued beamforming coefficient of a set of second analog complex-valued beamforming coefficients.

Cross-polar discrimination (XPD) of a dual orthogonal cross-polarized antenna is maximized via a cross-coupling network between base station MIMO branches prior to connection to the base station antenna. In one embodiment, a cross coupling network combines each MIMO branch signal with an attenuated phase reversed (phase shifted) copy of the other MIMO branch signal. The amount of attenuation for each branch is equivalent to the cross polar suppression required for each antenna array. The cross-coupling can be applied at different stages of signal processing within a base station.

An antenna system and method utilize a splitter electrically connectable to a single antenna for splitting an RF signal into two signals. A variable phase shifter shifts the phase of one of the signals. A combiner combines the phase shifted and non-phase shifted signals to produce a conditioned signal. A quality examiner circuit changes the amount of phase shift provided by the variable phase shifter to produce a plurality of different conditioned signals. The quality examiner circuit then determines a quality of each conditioned signal and changes the phase shift again to provide the highest quality conditioned signal to a receiver.

Embodiments of the present invention disclose a co-channel dual polarized microwave device and a method. Frame synchronization is performed on a first receive signal processed by cross polarization interference cancellation and phase noise immunization is performed on the first receive signal processed by frame synchronization. Frame synchronization is performed on a second receive signal not processed by cross polarization interference cancellation and phase noise immunization is performed on the second receive signal processed by frame synchronization. The first receive signal processed by phase noise immunization and the second receive signal processed by phase noise immunization are selectively received according to a frame synchronization state signal and a signal quality signal. Delay alignment is performed on a selectively received signal according to the frame synchronization state signal to implement lossless switching in a selective receiving process.

Certain aspects of the present disclosure relate to methods and apparatus for wireless communication. More particularly, aspects of the present disclosure generally relate to techniques for wireless communications by a first apparatus comprising a first interface for obtaining, via at least one receive antenna, first and second training signals transmitted from a second apparatus via at least first and second transmit antennas having different polarizations, and a processing system configured to determine, based on the first and second training signals, one or more characteristics for different transmit-receive antenna pairs, each pair comprising one of the first and second transmit antennas and the at least one receive antenna, and generate, based on the one or more characteristics, a parameter indicative of a rotation of the first apparatus relative to the second apparatus.

A method and device for compensation of received signal components at a user equipment (UE) used for receiving signal components from a radio base station (RBS). The signal components have at least a first and a second polarization orientation, respectively. The intended reception of the signal component (Yh(n)) having the first polarization deviates from the polarization orientation of the transmitted signal component (Xh(n)) having the first polarization by a first angle (φ), and the intended reception of the signal component (Yv(n)) having the second polarization deviates from the polarization orientation of the transmitted signal component (xv(n)) having the second polarization by a second angle (β). The method comprises the steps: determining the correlation values (Ryw, Ryvy, Ry_yv, Ry_yy) for the received signals (Yh, Yv) at a first time (k) and a second time (m); using these values to determine the deviation angles (φ, θ) performing said compensation using the deviation angles (φ, θ).

A wireless device includes a first antenna and a second antenna that may be used to communicate with a wireless network. The wireless device initiates a traffic call with a wireless network and activates a first antenna to be used to communicate with the wireless network upon initiating the traffic call. The wireless device selectively activates a second antenna, when initiating the traffic call, based at least in part on a usage of the second antenna during a previous traffic call. For example, the wireless device may maintain the second antenna in an inactive state if the second antenna was deactivated during the previous traffic call and/or remained inactive for at least a threshold duration.

In order to improve the efficiency of removing a component of a signal different from a target received signal, a transmission apparatus includes: a reception means for receiving a first signal transmitted by a first transmission apparatus, and removing a component of a second signal transmitted by a second transmission apparatus, the second signal being received along with the first signal, using a third signal inputted from a third transmission apparatus receiving the second signal; a control means for setting a first modulation method based on the first signal, and generating first information, the first information being information including directions to change a modulation method of the first signal and a modulation method of the second signal to the first modulation method; and a transmission means for transmitting the first information to the first transmission apparatus.

The invention relates to a radio communication receiver receiving a radio signal (S) including a main polarisation (MAIN-POL) and a secondary polarisation (X-POL) orthogonal to the main polarisation (MAIN-POL), the receiver including: a unit (1) for receiving the main polarisation (MAIN-POL) and the secondary polarisation of the received signal, synchronised as a carrier frequency with the main polarisation (MAIN-POL); a unit (2) for cancelling out the secondary polarisation synchronised with the main polarisation (MAIN-POL) and configured to suppress, from the received signal (S), the interference due to the secondary polarisation (X-POL), the unit (2) for cancelling out the secondary polarisation including a filtering unit (21) that receives the main polarisation (MAIN-POL) and the secondary polarisation (X-POL) as input; a unit (3) for demodulating the filtered signal, located downstream of the cancellation unit and configured to calculate carrier frequency error information and to communicate same by feedback to the upstream receiving unit (1).