Abstract:
Systems and methods for enabling a wireless backhaul network between access points (APs) in a wireless network are provided. In an embodiment, the wireless backhaul network is enabled using a Massive Multiple Input Multiple Output (MIMO) radio access technology (RAT). In another embodiment, the wireless backhaul network is established using the same RAT as used by the APs to serve user devices, and can utilize the same time and frequency resources used for user communication.
Abstract:
As wireless networks evolve, network providers may utilize legacy LTE devices as well as devices that support massive multi-input, multiple output (M-MIMO). Systems and methods for simultaneously servicing legacy LTE devices and M-MIMO devices are provided. In embodiments, a transmission zone for M-MIMO communications is defined within a legacy, non M-MIMO radio frame. The location of the M-MIMO transmission zone is transmitted to user devices. For example, an identification of the location of the M-MIMO transmission zone is transmitted in a system information message. In a further example, the location of the M-MIMO transmission zone is transmitted in the downlink control information. The location of the M-MIMO transmission zone may be defined dynamically based on a variety of criteria. In addition or alternatively, a set of pre-defined transmission zones may be utilized.
Abstract:
For an infinite number of transmit antennas at a base station (BS), matched filter (MF) precoding (a type of precoding used to perform SU-MIMO transmission) becomes optimal for performing spatial multiplexing. But observations have shown that precoding types for performing MU-MIMO transmission can perform significantly better than MF precoding for a realizable number of transmit antennas at the BS, even while using the simplest precoding types for MU-MIMO transmission. For large inter-cell interference typically encountered by user terminals (UTs) at or near the boundary of the cell served by the BS, MF precoding can still be used to eliminate or reduce the need for coordination among cells, which consumes network and back-haul resources.
Abstract:
Embodiments recognize that in MIMO and M-MIMO systems, physical antennas tend to be closely spaced to each other (e.g., a grid). As a result, a spatial correlation typically exists between physical antennas as well as between transmissions from logical antenna ports. Embodiments exploit this characteristic to reduce the amount of pilot signaling needed to enable downlink channel estimation. Specifically, embodiments limit pilot signaling to only a subset of supported logical antenna ports and rely on spatial correlation information to interpolate channels from logic antenna ports for which no pilot signaling is used.
Abstract:
Embodiments provide systems and methods for enabling a first transceiver to learn beamforming weights (e.g., Eigen beamforming weights) to a second transceiver, without any pilot signaling or explicit beamforming weight signaling from the second transceiver. In another embodiment, beamforming weight vectors to enable a multi-symbol spatial rate can be learned by the first transceiver.
Abstract:
Embodiments recognize that in MIMO and M-MIMO systems, physical antennas tend to be closely spaced to each other (e.g., a grid). As a result, a spatial correlation typically exists between physical antennas as well as between transmissions from logical antenna ports. Embodiments exploit this characteristic to reduce the amount of pilot signaling needed to enable downlink channel estimation. Specifically, embodiments limit pilot signaling to only a subset of supported logical antenna ports and rely on spatial correlation information to interpolate channels from logic antenna ports for which no pilot signaling is used.
Abstract:
Multiple input multiple output systems using a transmit precoder codebook designed for a four-transmitter (4Tx) antenna configuration are described. The 4Tx antenna configuration is an attractive option for base stations in cellular network environments and it is desirable to use a transmitter precoder codebook that provides sufficient granularity in typical operating scenarios, and to address various antenna configurations. In an embodiment, the transmit precoder codebook can be used for a variety of transmit antenna configurations including uniform linear antenna arrays, cross-polarized antenna arrays and uncorrelated antenna arrays. In another embodiment, the transmit precoder codebook is a two-component codebook, with a first precoder component signaled at a first rate and a second precoder component signaled at a second higher rate.
Abstract:
Systems and methods for channel assignment configuration in a multiple access point (AP) environment are provided. The multiple APs can be homogeneous or heterogeneous and can implement one or more radio access technologies (RATs), including Massive Multiple Input Multiple Output (M-MIMO) RATs. A channel assignment configuration for a user equipment (UE) can identify one or more communication channels to be established to serve the UE by one or more of the APs.
Abstract:
A framework for enabling a user equipment (UE) to apply interference suppression processing during network conditions that are favorable to interference suppression or that are known is provided. The framework includes an interference suppression (IS) time and frequency (time/frequency) zone, which can be scheduled by a serving base station and signaled to the UE. In an embodiment, the serving base station coordinates with the interfering base station(s) to create a network condition favorable to interference suppression at the UE during the IS time/frequency zone. In another embodiment, the serving base station opportunistically schedules the IS time/frequency zone for the UE whenever it determines favorable transmission parameters being used or scheduled for use by the interfering base station(s). The UE applies interference suppression processing within the IS time/frequency zone, thereby improving receiver performance. Outside the time/frequency zone, the UE may disable interference suppression processing so as not to degrade receiver performance.
Abstract:
Antenna systems and methods for Massive Multi-Input-Multi-Output (MIMO) (M-MIMO) communication are provided. Antennas systems include a M-MIMO transmitter architecture with a hybrid matrix structure. The hybrid matrix structure protects against transmit path component failures and ensures that a spatial rate of the MIMO transmitter is not degraded by the failures. Antenna systems and methods also include antenna selection schemes for selecting a subset of antennas from a plurality of antennas to transmit to a receiver.