485 results about "Interference management" patented technology

A method called the evolvable interference management (EIM) method is disclosed in this patent for avoiding interference and collision and increasing network throughput and energy efficiency in wireless networks. EIM employs sensitive CSMA / CA, patching approaches, interference engineering, differentiated multichannel, detached dialogues, and / or spread spectrum techniques to solve the interference and QoS problems. EIM-based protocols can considerably increase network throughput and QoS differentiation capability as compared to IEEE 802.11e in multihop networking environments. Due to the improvements achievable by EIM, the techniques and mechanisms presented in this application may be applied to obtain an extension to IEEE 802.11 to better support differentiated service and power control in ad hoc networks and multihop wireless LANs. New protocols may also be designed based on EIM.

A system and method are described herein employing a plurality of distributed transmitting antennas to create locations in space with zero RF energy. In one embodiment, when M transmit antennas are employed, it is possible to create up to (M−1) points of zero RF energy in predefined locations. In one embodiment of the invention, the points of zero RF energy are wireless devices and the transmit antennas are aware of the channel state information (CSI) between the transmitters and the receivers. In one embodiment, the CSI is computed at the receivers and fed back to the transmitters. In another embodiment, the CSI is computed at the transmitter via training from the receivers, assuming channel reciprocity is exploited. The transmitters may utilize the CSI to determine the interfering signals to be simultaneously transmitted. In one embodiment, block diagonalization (BD) precoding is employed at the transmit antennas to generate points of zero RF energy.

When a subscriber station (SS) encounters interference caused an interfering base station (BS), the interference can be mitigated regardless of whether the interfering base station is a CSG-Closed BS or whether the SS is connected to a serving BS. If the SS is not connected to a serving BS and cannot access the interfering BS, the SS will signal the interfering BS directly to request the interfering BS to perform IM. If the SS is a legal user, and conditions to initiate IM are met, the interfering BS will perform IM until conditions to terminate IM are met. If the SS is connected to a serving BS, the serving BS will request the interfering BS to perform or terminate interference mitigation (IM) on behalf of the SS if certain conditions are satisfied.

The present invention increases the available spectrum in a wireless network by sharing existing allocated (and in-use) portions of the RF spectrum in a manner that will minimize the probability of interfering with existing legacy users. The invention provides interference temperature-adaptive waveforms, and a variety of physical and media access control protocols for generating waveforms based on measurement and characterization of the local spectrum. The invention measures the local spectrum at a receiving node, generates an optimal waveform profile specifying transmission parameters that will water-fill unused spectrum up to an interference limit without causing harmful interference to primary and legacy transmitters using the same frequency bands, and enables simultaneous transmit and receive modes at a multiplicity of transceivers in a wireless network. The invention also provides closed loop feedback control between nodes, co-site interference management, intersymbol interference mitigation, wide sense stationary baseband signaling and modulation, and power limited signaling for avoiding detection and interception.

Interference management in a wireless network is disclosed in this document. Two networks with overlapping frequency bands and coverage areas are configured to cooperate in order to mitigate mutual interference. Some embodiments relate to medium reservation in a first network to protect a transmission in a second network, while other embodiments relate to aligning communication parameters between the networks.

A scheme to reduce the problem of radio interference between wireless devices such as MTC devices in a multi-RAT scenario. Wireless devices are configured (S10) for interference reporting in accordance with their capabilities. Information is collected, not only on interference measurements reported by the wireless devices, but also on device signatures (S12) and transmission patterns (S14) for the purpose of attributing interference, suffered by a reporting device, to one or more offending devices (S16). One or more mitigation techniques is then applied to the offending device and / or the reporting device (S20-S24). The scheme provides an additional stability mechanism for existing interference mitigation and co-existence schemes by using device management and avoiding potential conflicts across diverse systems. Under the assumption that geographically co-located devices are all using a common service platform, the centralised algorithm permits more efficient solutions than existing interference mitigation solutions.

Systems and techniques for managing the use of almost blank subframes in wireless communication systems. Base stations in a wireless network monitor load information affecting network nodes. Load information may be in the form of load metric information. The load information may be exchanged between system elements, and an almost blank subframe proportioning may be updated by one or more of the base stations, and information relating to the updated proportioning. The updated almost blank subframe proportioning may be used in scheduling and load metric calculation, as well as almost blank subframe patterning. Updating of almost blank subframe information and load metric information may be performed iteratively.

The specification and drawings present a new method, apparatus and software related product (e.g., a computer readable memory) for network management through a hierarchical architecture with a control functionality of a network server (e.g., C-SON) in relationship to clusters comprising eNBs (access points), and for implementing coordinated multi-point (CoMP) transmission and reception in conjunction with inter-cell interference coordination (ICIC) in wireless networks such as LTE wireless networks. In particular, embodiments of the invention describe control and coordination mechanisms among the network elements for different network architectures and use-case scenarios. Such mechanisms may be managed by a centralized self-organizing network controller such as C-SON and hierarchically via localized controllers (such as cluster coordinators) residing in macro eNBs depending on system architectural constraints and network state. A fault-tolerant mechanism then may be defined to recover from failure of controlling sub-elements so that the network remains stable at all times.

Systems, methods, apparatus and computer program products for scheduling in a wireless communication system are provided. In some embodiments, the method can include: receiving a buffer status report from user equipment having one or more logical channel groups; configuring a first priority metric and a first prioritized bit rate for at least one of the one or more logical channel groups, wherein the configuring a first priority metric and a first prioritized bit rate for at least one of the one or more logical channel groups is in response to information included in the buffer status report; determining interference at the user equipment; and re-configuring, by the serving base station, the first priority metric and the first prioritized bit rate for the at least one of the one or more logical channel groups in response to determining interference at the user equipment.

In an environment in which a macro base station and a low transmission power base station exist, the ratio of the interference reduction time period of the macro base station is optimized, and the throughput of the low transmission power base station is improved, while minimizing a reduction in throughput. The macro base station causes a high interference to other base stations and one or a plurality of low power nodes (LPN) subjected to interference from the macro base station. The macro base station sets first and second data transmission time periods and then determines the ratio of the second time period and the pattern of the first time period and the second time period based on communication quality in the first time period and communication quality in the second time period of the macro base station and the LPN.

User equipment (UE), referred to herein as an interfering UE (130), can be detected that is proximate to a low-power cell (120), such as a micro-cell, pico-cell, femto-cell, a relay, or the like. The interfering UE (130) can be transmitting to the base station (110) at a power level that is producing high interference affecting uplink performance between a different UE and the low-power cell (120). A power adjustment message (140) can be generated at the base station (110). The power adjustment message (140) can be conveyed (156) from the base station (110) to the interfering UE (130). The power level adjustment message (130) can cause the interfering UE (130) to lower its transmission power (164), which reduces the high interference, thereby improving uplink performance between the different UE and the low-power cell (120).

Notifying served user equipments (UEs) of the presence or absence of cell-specific reference signal (CRS) symbols transmitted by neighboring base stations in the physical downlink shared channel (PDSCH) region of a subframe can be achieved through various of signaling techniques. The served UE may be notified by communicating a one or multi-bit indicator in a physical layer signaling channel of the serving cell, such as the physical downlink control channel (PDCCH) of the subframe. Alternatively, the served UE may be notified through higher layer signaling.

A system and method for inter-cell power control for interference management in an OFDM system is provided. The system provides for a combination use of open loop and closed loop PSD control algorithms. The open loop control is a function of path loss from the serving cell as well as the neighboring cells. The closed loop control updates the end node transmit PSD by listening to the load indicators from the serving cell and at least one other neighboring non-serving cell which generates the highest level of interference. The system thus provides a fast and tight control with multi-cell information that allows improved inter-cell interference control.

The present invention increases the available spectrum in a wireless network by sharing existing allocated (and in-use) portions of the RF spectrum in a manner that will minimize the probability of interfering with existing legacy users. The invention provides interference temperature-adaptive waveforms, and a variety of physical and media access control protocols for generating waveforms based on measurement and characterization of the local spectrum. The invention measures the local spectrum at a receiving node, generates an optimal waveform profile specifying transmission parameters that will water-fill unused spectrum up to an interference limit without causing harmful interference to primary and legacy transmitters using the same frequency bands, and enables simultaneous transmit and receive modes at a multiplicity of transceivers in a wireless network. The invention also provides closed loop feedback control between nodes, co-site interference management, intersymbol interference mitigation, wide sense stationary baseband signaling and modulation, and power limited signaling for avoiding detection and interception.

A central base station for interference management in a distributed antenna system comprises a processor; a memory; and a frequency partition module configured to divide the remote radio heads into clusters and allocate a frequency band to each cluster. Multiple clusters use the same frequency band and groups of clusters are formed. A joint scheduler is configured, for each group, to activate at most two clusters at any given time and deactivate remaining clusters in the group, one of the at most two activated clusters being a serving cluster of the group, and to associate one or more users with the serving cluster in the group. An interference alignment module is configured to apply downlink interference alignment between the at most two activated clusters in each group to align transmit directions of all interferences between the at most two activated clusters.

Channel reservation systems and methods are disclosed herein, which schedule transmissions on a shared radio medium that is shared by a plurality of licensed network operators. In embodiments, priority access is pre-assigned to the network and the method determines whether to send a transmission based at least on the transmitter's priority class as compared to another transmitter's priority class and to which transmitter the time slot of a signal is dedicated. In embodiments, priority access may not be preassigned to the network and pre-grants may be used in conjunction with CR-Ts and CR-Rs to determine whether a transmitter transmits.

Techniques are provided to manage interference for soft handoff and broadcast services in a wireless frequency hopping communication system (e.g., an OFDMA system). These techniques may be used for the forward and reverse links. In a first scheme, an FH function ƒsho(r,T) is used for soft-handoff users, an FH function ƒs<sub2>i< / sub2>(k,T) is used for users not in soft handoff in each sector si, and the FH function ƒs<sub2>i< / sub2>(k,T) is modified to be orthogonal to the FH function ƒsho(r,T) if and when necessary. In a second scheme, the FH function ƒsho(r,T) used for soft-handoff users is defined to be orthogonal to or have low correlation with the FH function ƒs<sub2>i< / sub2>(k,T) used for users not in soft handoff in each sector si, so that modification of the FH function ƒs<sub2>i< / sub2>(k,T) is not needed. The FH function ƒs<sub2>i< / sub2>(k,T) for each sector may be defined to be pseudo-random with respect to the FH functions ƒs<sub2>i< / sub2>(k,T) for other sectors.

The invention comprises a mesh access network architecture that provides a combination of high data rates to a large number of users and >99% coverage to potential customers in a service area. The network design also provides scalable capacity that scales to more capacity / users with additional frequency carriers and coverage over a large area with additional base-stations. This is achieved using a combination of centralized mesh network control and intelligent interference management.

The specification and drawings present a new method, apparatus and software related product (e.g., a computer readable memory) for network management through a hierarchical architecture with a control functionality of a network server (e.g., C-SON) in relationship to clusters comprising eNBs (access points), and for implementing coordinated multi-point (CoMP) transmission and reception in conjunction with inter-cell interference coordination (ICIC) in wireless networks such as LTE wireless networks. In particular, embodiments of the invention describe control and coordination mechanisms among the network elements for different network architectures and use-case scenarios. Such mechanisms may be managed by a centralized self-organizing network controller such as C-SON and hierarchically via localized controllers (such as cluster coordinators) residing in macro eNBs depending on system architectural constraints and network state. A fault-tolerant mechanism then may be defined to recover from failure of controlling sub-elements so that the network remains stable at all times.

In a network containing a macro base station and wireless access points within the range of the macro base station, information from wireless access points are used to change the quantity of almost blank subframes delivered by the macro base station, adjust the cell range extension area of one or more of the wireless access points, or provide instructions to alter the number of wireless access points. The information is analyzed. The analysis allows determination of a capacity gain associated with using the wireless access points within an area associated with the macro base station and whether the capacity gain provides at least a threshold amount of gain permitting the macro base station and the wireless access points to provide service to mobile devices within the area.

Aspects of the present disclosure provide various wireless communication numerology designs that can maintain symbol boundary alignment while multiplexing different numerologies in wireless communication. The symbols may be scaled for different tone or subcarrier spacings while maintaining the symbol boundary alignment between different numerologies. Maintaining the symbol-boundary alignment between different numerologies enables symbol-level numerology multiplexing. The disclosed numerology designs enable low latency communication and improved interference management, and provide non-ambiguous symbol boundary timing reference for multiplexing different numerologies.

Systems and methodologies are described that provide techniques for generating and utilizing reverse link feedback for interference management in a wireless communication system. Other Sector Interference (OSI) indicators are transmitted from an interfering access point to an access terminal. At the access terminal, an appropriate delta value(s) is combined with the received OSI indicators. The combined information is transmitted to the access point in a feedback so the serving sector access point can analyze the amount of interference. Based on the provided feedback from the terminal, the serving sector access point can assign resources for use by the terminal in communication with the serving sector.

A method of configuring small cell base stations in a cellular network is disclosed. A constraint on a performance-related metric associated with at least a portion of the cellular network is received. In some embodiments, the constraint on the performance-related metric comprises a constraint on a performance-related metric associated with one or more macrocells. Measurement data from one or more small cell base stations is received via a control interface. One or more optimized values of one or more parameters associated with one or more small cell base stations are searched. The searching is based at least in part on the received measurement data and subject to the constraint on the performance-related metric associated with the at least a portion of the cellular network. The one or more optimized values of the one or more parameters to the associated small cell base stations are transmitted.

Protocols for OFDM / OFDMA / SC-FDMA based wireless networks provide adaptive inter-cell interference management without explicit spectrum or frequency planning. Base stations and mobile stations acquire information about subcarrier allocation from a handoff protocol. The mobile stations can also acquire this information using cognitive sensing. Cognitive sensing can be rewarded by the base station. Using this information, subcarriers can be allocated randomly, with blind optimization, or by joint optimization. The stations can use game theory to select among the different optimization strategies.

Communication systems, such as the long term evolution (LTE) advanced (LTE-A) of the third generation partnership project (3 GPP) may benefit from various enhancements. These enhancements can include LTE time division duplex (TDD) enhancements for traffic adaptation and uplink (UL)-downlink (DL) interference management. A method can include determining whether a first cell, in a network including the first cell and a second cell, autonomously selects a time division duplex uplink-downlink configuration. The method can also include sending an authority indicator to a base station of the first cell regarding a determination of whether the first cell is to autonomously select the configuration.

The embodiment of the invention discloses a method and a device for managing user equipment. A long-term evolution distributed antenna system (LTE DAS) cell comprising a plurality antenna units (AU) is divided into a plurality of subareas; the subareas correspond to one or more Aus; and in the cell, the subarea is adopted as a unit so as to schedule resources for the UE and carry out interference control and mobile management. By application of the invention, the efficiency in interference management and switching can be improved, and the system capacity is increased.

The invention discloses a radio monitoring electromagnetic situation prediction system which is characterized in that the system comprises a radio electromagnetic situation data acquisition equipment system, a station database, a radio electromagnetic situation index parameter prediction system, an alarm system, a network communication system and a processing controller; the data acquisition equipment system receives electromagnetic wave in the air and carries out conversion processing to generate electromagnetic monitoring data including frequency sweeping data, voice data, intermediate frequency data, signal azimuth data and the like; radio electromagnetic situation index parameter prediction system firstly calculates radio situation index parameters according to the monitoring data, builds a training dataset by the use of the index parameter data and predicts values of the parameters at the next time through training and learning; the network communication system is responsible for communications between modules of the system and between the system and other external equipment; and the processing controller is in charge of coordinating processing scheduling between modules. By the adoption of the prediction system, crises are prevented before they emerge; current radio monitoring level is raised; and losses caused by radio interference and lag management are reduced.