150results about How to "Reduce interference" patented technology

A satellite radiotelephone frequency band can be reused terrestrially by an ancillary terrestrial network even within the same satellite cell, using interference reduction/cancellation techniques. An interference reducer is responsive to a space-based component and to an ancillary terrestrial network. The interference reducer is configured to reduce interference in wireless communications that are received by the space-based component from first radiotelephones in the satellite footprint over a satellite radiotelephone frequency band using wireless communications that are received by the ancillary terrestrial network from selected ones of second radiotelephones in the satellite footprint over the satellite radiotelephone frequency band and/or wireless communications that are transmitted by the ancillary terrestrial network to the second radiotelephones in the satellite footprint over the satellite radiotelephone frequency band. The interference reducer may include a prefilter that is configured to determine the selected ones of the second radiotelephones.

An image detection apparatus comprises a light source and a holding apparatus adapted to hold a substrate on which a biological sample may be mounted. Light from the light source impinges on the biological sample and causes light that is representative of the sample to be emitted from the sample. A light detector is positioned in the path of the emitted light and is scanned across the emitted light. The emitted light may be focused on the light detector with an optical assembly. The emitted light may be generated by chromophores on probes in the biological sample.

There is provided a system, apparatus and methods for the laser drilling of a borehole in the earth. There is further provided with in the systems a means for delivering high power laser energy down a deep borehole, while maintaining the high power to advance such boreholes deep into the earth and at highly efficient advancement rates, a laser bottom hole assembly, and fluid directing techniques and assemblies for removing the displaced material from the borehole.

A method of reducing interference to reception of streams of television content received at a television receiver in which each of the streams of television content are transmitted on one of a plurality of frequency channels in accordance with a channel map which defines on which of the plurality of frequency channels each stream of television content is transmitted and the interference being caused by a base station transmitting data to or receiving data from one or more mobile devices via radio communication signals in a vicinity of the television receiver. The method includes identifying the channel map and adapting a transmission of the radio communication signals between the base station and the one or more of mobile devices in accordance with the identified channel map to reduce interference at the television receiver.

A mobile station is disclosed that includes a first antenna, at least one second antenna, and a receiver coupled to the first antenna. The receiver includes first control logic configured to generate a notification of the receiver being able to receive a reception frequency band and includes a transmitter coupled to the at least one second antenna and the receiver. The transmitter communicates radio frequency (RF) signals in a transmission frequency band over an RF transmit path to the at least one second antenna. The transmitter includes a tunable filter coupleable to the RF transmit path, and second control logic configured to adjust at least one characteristic of the tunable filter based at least in part on the notification. The adjustment is performed to reduce, when the tunable filter is coupled to the RF transmit path, interference caused by transmission in the transmission frequency band with reception in the reception frequency band.

In wireless system, a group of Basestations (BTSs) can be managed by a centralized network management identity or can be self-organized by communicating with each other via wireless air-interfaces or wired interfaces. One such example are Femtocell systems. When the BTSs are using the same frequency for transmitting and receiving with relatively large transmitting power and when they are closer to each other, performance of such a system and user throughput or QoS (Quality of Service) gets degraded due to the interference between the BTSs and among the users. Smart antenna technique can be used in a coordinated way among a group of BTSs, such as Femtocells, to avoid or reduce interference or manage how interference happens to achieve performance enhancement such as higher system throughput or better QoS to individual applications.

An apparatus and method for reducing interference over a common communication medium, wired or wireless is provided. The apparatus reduces interference from a number of sources using a common architecture which may be used to service a modem pool or discrete modems which share the common communication medium. Interference due to near end cross-talk (NEXT), self-NEXT or echo, and far end cross-talk (FEXT) may all be substantially reduced or cancelled by the apparatus. Additionally, channel characteristics for individual data channels across the common communication medium may be determined. The apparatus provides support for multiple modem protocols including X-DSL protocols such as G.Lite, ADSL, VDSL, SDSL, MDSL, RADSL, and HDSL. The apparatus supports multiple line codes such as the discrete multi-tone (DMT) and carrier less AM/PM (CAP) line codes associated with X-DSL communications. The apparatus may be implemented in hardware, firmware or software. The apparatus has a compact form factor due to pooling of the interference canceling elements.

The present invention relates to method for controlling the transmission timing of data retransmissions in a wireless communication system wherein a HARQ retransmission protocol, is used to retransmit data from a transmitting entity to a receiving entity via a data channel. Further the present invention relates to a base station, a mobile terminal and a communication system employing the present invention. To overcome problems resulting from synchronous retransmissions in interference critical situations, the present invention introduces additional feedback signaling to a new HARQ protocol. The new NACK-S indicates to the transmitting entity to stop the synchronously transmitting retransmissions but to await a scheduling assignment for the retransmission from the receiving entity instead.

A novel method and apparatus for performing cell selection handoffs in a wireless communication system is disclosed. The CSHO method and apparatus of the present invention determines which transmitters to temporarily disable or “gate off” during soft handoff procedures. The method and apparatus of the present invention monitors the channel conditions for all base stations in an active set of a selected mobile station and determines the relative strengths of base stations based on the monitored channel conditions. The method and apparatus of the present invention reduces interference to receivers in a wireless communication system. Specifically, the present invention temporarily disables, or “gates off” selected transmitters (e.g., base stations) during soft handoff procedures and thereby reduces interference to receivers that are not associated with the selected transmitters. Reducing this interference increases the overall voice and data capacity in a wireless communication system.

Pilot signal transmission sequences and methods for use in a multi-sector cell. Pilots in different sectors are transmitted at different known power levels. In adjacent sectors a pilot is transmitted while no pilot is transmitted in the adjoining sector. This represents transmission of a NULL pilot signal. A cell NULL is also supported in which NULL pilots are transmitted in each sector of a cell at the same time. Multiple pilot signal measurements are made. At least two channel quality indicator values are generated from measurements corresponding to at least two pilot signals of different power levels. The two values are transmitted back to the base station which uses both values to determine the transmit power required to achieve a desired SNR at the wireless terminal. The wireless terminal also reports information indicating its location to a sector boundary.

In a mobile communication system that switches a base station, with which a mobile terminal communicates in a cell boundary, from a first base station to a second base station according to handover control, the mobile terminal notifies assignment information on a radio resource assigned by the first base station, to the second base station during handover period, and the second base station collects the assignment information, and assigns a radio resource to a mobile terminal existing in its own cell based on the collected radio resource assignment information, so that interference from the first base station is decreased.

Embodiments of the present invention are directed to a cable assembly that is adapted to be connected to an antenna and a base unit. The cable assembly may be relatively flat with shielding and structures to reduce ground currents or other interference. Embodiments of the cable assembly include at least two coaxial cables for transmit and receive signals that are separated to reduce crosstalk or other interference. The cable may also include one or more inner cables, such as differential or switching pairs, between the two coaxial cables to provide cables for control, power, switching, or other functions. The inner cables may be positioned in parallel to each other and to each of the coaxial cables. In some embodiments, the inner cables include a first inner cable located at a first end of the inner cables and a second inner cable located at a second end of the inner cables. One coaxial cable may be positioned adjacent and parallel to the first inner cable, which the other coaxial cable may be positioned adjacent and parallel to the second inner cable.

A radio communication system carrying out uplink scheduling so as to reduce interference at a base station apparatus even when there are communication terminal apparatuses in the process of soft handover. In this system, a separation section (110) of a communication terminal apparatus separates a result of demodulation of a received signal into received data and a transmit power control (TPC) command instructing an increase or decrease of transmit power, a base station selection section (120) selects a main base station apparatus having the best channel quality according to the TPC command and outputs base station selection information. Furthermore, a transmit power control section (130) of the communication terminal apparatus determines transmit power according to the TPC command and an extra transmit power calculation section (140) calculates extra transmit power by subtracting the determined transmit power from maximum transmittable transmit power and outputs extra transmit power information. Furthermore, a selection/multiplexing section (150) of the communication terminal apparatus multiplexes transmission data, base station selection information and extra transmit power information and a transmission section (160) transmits the multiplexed data to the base station apparatus.

A wireless communication system includes a macro-base station device and a CGS base station device normally connected to a CSG terminal device. When a non-CGS terminal device approaches the CGS base station device, the CGS base station device reduces a frequency band for transmitting packets to the CGS terminal device so as to reduce interference with the non-CGS terminal device while increasing transmission power to the CGS terminal device so as to compensate for degradation of radio quality due to a reduction of the frequency band. Based on existence or nonexistence of a non-CSG terminal device in the coverage area, the CSG base station device selects an appropriate antenna transmission mode and an appropriate scheduler mode while setting the number of OFDM symbols utilized by a physical control channel in notifying radio resource allocation information.

A method and apparatus of transmitting data in a coordinated multi-cell wireless communication system is provided. A base station receives information about beam-forming vectors, aligned with a channel to a user equipment placed in a neighbor cell, and about nulling beam-forming vectors for the channel to the user equipment from the neighbor cell, determines a transmission beam-forming vector based on the information, and transmits data to the user equipment using the transmission beam-forming vector.

A tuner architecture is disclosed that mixes an analog RF input signal and a digital local oscillator signal to generate a output signal at a desired IF frequency, including low-IF and zero-IF solutions. The tuner provides a number of advantages over previous implementations, such as improved performance for low-IF and zero-IF architectures and a significant reduction in interference between adjacent paths in a multiple tuner solution. Other features and variations can be implemented, if desired, and related methods can be utilized, as well.

The various embodiments of the present invention relate generally to femto-relay systems and methods. An exemplary embodiment of the present invention provides a femto-relay system comprising a relay-radio, a femto-radio, a joint femto-relay resource management module, and an IP-backhaul QoS monitoring module. The relay-radio is in communication with a macro-cell base-station. The femto-radio is in communication with the relay-radio and configured to route signals between a core network and at least one femto-cell user equipment through an IP-backhaul link. The joint femto-relay resource management module is configured to intelligently manage radio resources between the femto-radio and the relay-radio to reduce cross-tier interference. The IP-backhaul QoS monitoring module is configured to monitor a QoS being delivered by the IP-backhaul link and notify the relay-radio to route signals between the femto-cell user equipment and core network through the macro-cell base-station if the QoS fall below a predetermined threshold.

A system and method for transmitting and receiving signals in a communication system are provided, in which a BS communicates with a first MS located within an inner area of a cell during first and second time periods in TDD and communicates with a second MS located within an outer area of the cell during the first time period in FDD, and an RS detects signals transmitted between the BS and the second MS during the first time period and transmits the detected signals simultaneously to the BS and the second MS during the second time period.

Methods and systems are provided for operating an engine with variable displacement engine (VDE) operation coupled to a twin scroll turbocharger. One method comprises directing exhaust from a first outer cylinder and a first inner cylinder of four cylinders to a first scroll of the twin scroll turbocharger, directing exhaust from a second outer cylinder and a second inner cylinder of the four cylinders to a second scroll of the twin scroll turbocharger, and during a first condition, firing all four cylinders with uneven firing.

A method to be performed by a network system is proposed, for P2P communication to cancel interference, comprising steps of: determining the redundant code group information, according to the code group usage information of the cell in which two UEs to establish P2P connection camp and its adjacent cells; detecting the relative position between said two UEs and each of other active UEs in communication state in the cell where said two UEs are camping and its adjacent cells; if at least one UE of said two UEs causes radio interference to at least one of said active UEs according to the relative position, further determining whether said UE and said active UE are assigned in the same time slot; selecting a scrambling code from the redundant code group information and assigning it to said two UEs if said UE and said active are assigned in the same time slot, so that said two UEs can perform scrambling operation by using said scrambling code on P2P signals transferred between said two UEs.

A method of controlling interference in a wireless communication system is disclosed. A method for controlling interference by a transmitter of a wireless communication system with multiple antennas comprises generating a base codebook subset including at least one precoding matrix selected from a base codebook; transmitting a base codebook subset indication, which represents the at least one precoding matrix included in the base codebook subset, to a receiver; and precoding data using the base codebook subset or the base codebook.

A dielectric element is formed of a dielectric material exhibiting a magnetic resonance relaxation time, with a relaxation agent incorporated in the dielectric material that reduces the relaxation time of the dielectric material. The dielectric element is adapted for placement on a subject while magnetic resonance data are acquired from the subject, and locally influences the B₁ field distribution in the subject during the acquisition of magnetic resonance data.

A method of assigning a carrier for mitigating inter-cell interference in a fixed relay based communication system is provided. In a normal mode, the method includes defining at least one sector group by grouping cells at least two tiers away from each other; selecting a single sector group; and assigning, by a base station of the selected sector group, a first carrier to a relay station or a mobile station which is located in a coverage area of the base station. In a relay mode, the method includes determining whether a current mode is a normal mode or a relay mode; determining whether a base station is included in a selected sector group; and assigning carriers to a relay station or a mobile station belonging to the base station, when the current mode is the normal mode and the base station is included in the selected sector group.

A system for reducing electromagnetic interference between two or more co-located antennas is described herein. In one embodiment, the system includes a first antenna for transmitting a first signal within a first frequency band, and a second antenna for operating within a second frequency band during transmission of the first signal. The first and second frequency bands may be substantially identical, or may occupy overlapping or nearby channels within the radio frequency spectrum. The system also includes an apparatus. In one embodiment, the apparatus is positioned proximate to the second antenna for intercepting the electromagnetic energy radiated from the first antenna during transmission of the first signal. In other embodiments, the apparatus may be positioned proximate to the first antenna for intercepting the electromagnetic energy radiated from the second antenna during transmission of a second signal. In either embodiment, the apparatus is able to reduce electromagnetic interference between the first and second antennas by scattering (or redirecting) radiated energy away from either the first antenna or the second antenna.

A method of transmitting a transmit vector comprising symbols to be delivered within a resource unit from a transmitting station with one or more transmit antennas to one or more receiving stations with one or more receive antennas. The method comprises obtaining information on the state of channels between the one or more transmit antennas and the one or more receive antennas; and computing, on the basis of the channel states between the one or more transmit antennas and the one or more receive antennas, a covariance matrix R_nn, a combined channel matrix H, and a block-diagonal linear operator V of decoding matrices of the receiving stations. The transmit vector is multiplied with a precoding matrix P fulfilling the equations

(H^HV^HVH=λI)P=H^HV^H

V_i(H_iPP^HH_i^H+R_nn,k)=P_i^HH_i^H

trace(P^HP)=P_tr

and corresponding performing filtering in the receiving station using a receiver filter corresponding to the block-diagonal linear operator V.

Embodiments of the present invention provide a method and a user equipment for cell selection of a heterogeneous network. The UE selects, a cell with a highest signal measurement value in a carrier frequency synchronizes to the cell, and receives broadcast information of the cell. If the cell is a macro cell, the broadcast information carries an extended indicator bit and the extended indicator bit is used to identify whether a low-power cell exists in the coverage of the macro cell. If the extended indicator bit identifies that the low-power cell exists in the coverage of the macro cell, the low-power cell in the macro cell is searched for, and if a low-power cell in the macro cell satisfies an S rule, the UE selects the lower-power cell as a serving cell and camps.

A mobile communication system wherein the upstream radio channel interference of a macrocell connection terminal with a femtocell base station can be reduced while the consumption of radio resources caused by increase in signaling is being suppressed. The macrocell connection terminal (401) performs, based on an instruction from a macrocell base station (402), an upstream channel transmission and further reports a peripheral-femtocell detection result obtained by a measuring unit to the macrocell base station. The macrocell base station (402) instructs the terminal to perform a peripheral-femtocell detection. The identifier of the terminal and the peripheral-femtocell detection result obtained by the terminal are transmitted to a network management apparatus (404). An interference reduction instruction (frequency band allocation) and the identifier of the terminal to be interference-controlled are received from the network management apparatus, and the frequency band allocation in the upstream channel transmission of the terminal to be interference-controlled is so controlled as to satisfy the interference reduction instruction.

Disclosed is a signal transmission method performed by a relay station in a wireless communication system. The method comprises the steps of: arranging guard time within at least one symbol period in a subframe which is configured with multiple symbol periods in a time domain; and transmitting a control signal or data to a base station by using symbol periods except for the symbol periods which include the guard time in the subframe. The guard time is equal to or shorter than one symbol period. The structure in which the control signal or the data is arranged in each symbol period of the subframe is determined on the basis of the number of symbol periods except for the symbol periods which include the guard time.

The present invention relates to an apparatus and method for reducing the interference caused by a femtocell in a wireless communication system. The method comprises the steps of: measuring the intensity of a signal received from a terminal when the transmission mode is deactivated; and controlling the transmission mode to be activated according to the signal intensity, and thus has the advantage of decreasing the influence effects caused by the femtocell and reducing the power consumption in a femto base station.

A frequency tunable transmit/receive (Tx/Rx) antenna switch uses a tuned PIN diode RF switch topology (e.g. shunt, series or series-shunt). Frequency tunability may be provided for either a transmit or a receive port (or both) that is tuned by a quarter-wavelength transmission line. The quarter-wavelength (λ_c/4) line establishes a passband centered about a center frequency f_c. An electronically tunable LC tank circuit adds capacitance to the switch impedance to shift the center frequency fc to lower frequencies and progressively narrow the passband with the addition of more capacitance. Transceiver units provided with frequency tunable Tx/Rx antenna switches can, for example, be used in a Master/Slave network in which multiple units communicate with each other or in an autonomous network in which each of the multiple units operate independently.