Abstract: Aspects of this disclosure provide techniques for computing Vandermonde-subspace frequency division multiplexing (VFDM) precoders for secondary network transmissions that mitigate interference between secondary communication signals, while avoiding interference with the primary system altogether. A precoder for a secondary user (SU) is computed on accordance with a nullspace induced by cyclic prefixes communicated over a primary data channel, a primary interference channel between a second user (SU) and the primary receiver, and a secondary interference channel between the SU and a neighboring SBS. The precoder provides both frequency domain precoding and spatial domain precoding on secondary transmission signals communicated from the SU.

Abstract: Embodiments are provided for interference avoidance based on signal alignment for multiple-input and multiple-output (MIMO) with orthogonal frequency-division multiplexing (OFDM) or OFDM access (OFDMA). The embodiments include a signal alignment scheme using both spatial and frequency dimensions. The scheme includes an existing link between an existing transmitter and an existing receiver, and a new link between a new transmitter and a new receiver. The new transmitter determines combinations of space dimensions and frequency dimensions unused in transmission on an existing link, and assigns signals for transmission on the new link at one or more of the unused combinations of space dimensions and frequency dimensions. The existing receiver is further configured to reallocate its power to release, using a greedy search algorithm, a small eigenvalue algorithm, or a best throughput algorithm, a null space of some space dimensions to the new transmitter.

Abstract: The invention provides a self-adaptive downlink power control scheme for OFDMA-based wireless cellular networks suitable for noise-limited environments. Downlink power levels are assigned in a distributed manner in the absence of any requirement for coordination or cooperation between cells. Distributed assignment allows for more optimal usage of the available transmit power at the base stations and more complete exploitation of the flexibility of frequency domain scheduling. In one embodiment, base stations in a cellular network service mobile user equipment within the respective base station coverage areas, and categorize the user equipment in a plurality of power levels according to certain criteria in accordance with such factors as channel experience and quality. A load-balancing self-adjustment mechanism allows automatic balancing of the load between different power levels.

Abstract: Virtualized group-wise communications between a wireless network and a plurality of user equipments (UEs) are supported using UE cooperation. UE cooperation includes receiving, at a cooperating UE (CUE), downlink information from the wireless network destined for a target UE (TUE) and associated with a group identifier (ID). The group ID indicates a virtual multi-point (ViMP) node that includes the TUE and the CUE. The UE cooperation also includes sending the downlink information to the TUE. The UE or UE component can have a processor configured to forward between the wireless network and a TUE at least some information that is associated with a group ID indicating a ViMP node that groups the TUE and the UE.

Abstract: Soft information for achieving interference cancellation in downlink transmissions can be communicated over device-to-device (D2D) links, thereby allowing paired user equipments (UEs) to receive downlink transmissions over the same radio resources. More specifically, paired UEs that receive transmissions over the same time-frequency resources may exchange soft or hard information over D2D links in order to facilitate interference cancellation. The D2D links may be unidirectional or bidirectional, and may be established over in-band or out-of-band resources. Paired UEs may be in the same or different cells, and may receive their respective transmissions from the same or different transmit point. UEs may be paired with one another based on various criteria, e.g., interference cancellation capabilities, scheduling metrics, etc.

Abstract: System and method embodiments are provided to support network communications with groups of UEs. The embodiments include a two-level group-based hybrid-automatic repeat request (HARQ) mechanism and acknowledgement (ACK)/negative ACK (NACK) feedback. An embodiment method includes receiving, at a UE within a virtual multi-point (ViMP) comprising UEs, a data packet for a target UE (TUE) that is broadcasted from a base station (BS) to the ViMP node, decode the data packet, and upon successfully decoding the data packet, broadcasting the data packet to the UEs within the ViMP node until a timer pre-established by the BS expires or an ACK message is received from the TUE or the ViMP node. In an embodiment, broadcasted data received in the ViMP node is re-broadcasted upon receiving a negative acknowledgment (NACK) message from the TUE, a beacon UE, or any of the UEs within the ViMP node.

Abstract: System and method embodiments are provided to achieve efficient Direct Mobile Communications (DMC) and device-to-device (D2D) communications for terminal based groups with improved spectrum efficiency, reduced interference, and virtual full duplex operation mode. The embodiments include a distributed mechanism for D2D communications that enables one or more cooperating UEs (CUEs) to help one or more target UEs (TUEs) with limited additional signaling overhead and relatively simple implementation. The mechanism comprises a grantless multi-dimensional multiplexing scheme that uses low density spreading (LDS) over time, frequency, and/or space domains to enable data forwarding between multiple half-duplex terminals or UEs while allowing the UEs to operate in virtual full-duplex mode.

Abstract: Virtualized group-wise communications between a wireless network and a plurality of user equipments (UEs) are supported using UE cooperation. UE cooperation includes receiving, at a cooperating UE (CUE), downlink information from the wireless network destined for a target UE (TUE) and associated with a group identifier (ID). The group ID indicates a virtual multi-point (ViMP) node that includes the TUE and the CUE. The UE cooperation also includes sending the downlink information to the TUE. The UE or UE component can have a processor configured to forward between the wireless network and a TUE at least some information that is associated with a group ID indicating a ViMP node that groups the TUE and the UE.

Abstract: The invention provides a self-adaptive downlink power control scheme for OFDMA-based wireless cellular networks suitable for noise-limited environments. Downlink power levels are assigned in a distributed manner in the absence of any requirement for coordination or cooperation between cells. Distributed assignment allows for more optimal usage of the available transmit power at the base stations and more complete exploitation of the flexibility of frequency domain scheduling. In one embodiment, base stations in a cellular network service mobile user equipment within the respective base station coverage areas, and categorize the user equipment in a plurality of power levels according to certain criteria in accordance with such factors as channel experience and quality. A load-balancing self-adjustment mechanism allows automatic balancing of the load between different power levels.

Abstract: A method for partitioning a communications network includes selecting, by a controller, a starting communications controller for a first region in the communications network according to an interference level. The method also includes including, by the controller, a first neighboring communications controller in the first region if an average inter-cell interference level of the starting communications controller and the first neighboring communications controller exceeds a first threshold and closing the first region if the average inter-cell interference level of the starting communications controller and the first neighboring communications controller fails to exceed the first threshold. The method further includes storing information about the first region in a memory.

Abstract: A method allocates bandwidth from a radio frequency spectrum in a cellular network including a set of cells. Each cell includes a base station for serving a set of mobile stations in the cell. An area around each base station is partitioned into a center region and an edge region. In each base station, cell-center bandwidth for use by the mobile stations in the center region is reserved according to an inter-cell interference coordination (ICIC) protocol, and cell-edge bandwidth for use by the mobile stations in the edge region is reserved according to the ICIC protocol. The bandwidth can be fixed or adaptive to reduce the signaling overhead. The adaptive bandwidth can be further partitioned into reserved and the free bands. Mobile stations are classified as primary and secondary users, depending on whether they use or are assigned the fixed or adaptive band radio resources.

Abstract: A method for allocating resources in an orthogonal frequency division multiple access (OFDMA) network, where each cell in the network has a center region and an edge region. The cell center region uses a frequency band orthogonal to the frequency band used by the cell edge region. The frequency band is made up of resource blocks (RBs) or non-overlapping sets of subcarriers. Upon availability of cell-center RBs, cell-center user equipment (UEs) are assigned resource blocks. A fixed number of cell edge regions from a few adjacent cells form a cluster, and only the cell edge regions with the highest achievable throughput rate within each cluster gets to transmit in a given scheduling instance.

Abstract: A location of an object is determined by arranging a sequence of bits on a substrate. The sequence of bits includes subsequence of bits, and each subsequence of bits is unique for each location along the substrate. When the object is at a particular location along the substrate a sensor detects the subsequence of bits at the particular location, and a decoder associates the location of the subsequence at the particular location with the object. The substrate can be a leaky coaxial cable with slits or not, corresponding to the bits, or lane markings on a road.

Abstract: A location of an object is determined by arranging a sequence of bits on a substrate. The sequence of bits includes subsequence of bits, and each subsequence of bits is unique for each location along the substrate. When the object is at a particular location along the substrate a sensor detects the subsequence of bits at the particular location, and a decoder associates the location of the subsequence at the particular location with the object. The substrate can be a leaky coaxial cable with slits or not, corresponding to the bits, or lane markings on a road.

Abstract: A method for allocating resources in an orthogonal frequency division multiple access (OFDMA) network, where each cell in the network has a center region and an edge region. The cell center region uses a frequency band orthogonal to the frequency band used by the cell edge region. The frequency band is made up of resource blocks (RBs) or non-overlapping sets of subcarriers. Upon availability of cell-center RBs, cell-center user equipment (UEs) are assigned resource blocks. A fixed number of cell edge regions from a few adjacent cells form a cluster, and only the cell edge regions with the highest achievable throughput rate within each cluster gets to transmit in a given scheduling instance.

Abstract: A method allocates bandwidth from a radio frequency spectrum in a cellular network including a set of cells. Each cell includes a base station for serving a set of mobile stations in the cell. An area around each base station is partitioned into a center region and an edge region. In each base station, cell-center bandwidth for use by the mobile stations in the center region is reserved according to an inter-cell interference coordination (ICIC) protocol, and cell-edge bandwidth for use by the mobile stations in the edge region is reserved according to the ICIC protocol. The bandwidth can be fixed or adaptive to reduce the signaling overhead. The adaptive bandwidth can be further partitioned into reserved and the free bands. Mobile stations are classified as primary and secondary users, depending on whether they use or are assigned the fixed or adaptive band radio resources.