Abstract: A method and system is disclosed for precoding in a two transmit antenna MIMO system, for example, a wireless backhaul network. The method only uses the first column of the 2×2 precoder as the feedback information. When the feedback information is available to the transmitter, the transmitter performs an interpolation and reconstruction procedure to obtain the precoder matrix for each subcarrier. The method offers no significant loss in performance, with reduced computational complexity and feedback overhead compared to conventional known matrix representation methods.

Abstract: A system and method of uplink power control in a fixed wireless backhaul network, wherein determining an uplink transmit power of each remote backhaul module (RBM) comprises obtaining an interference-over-thermal (IoT) noise value of each hub, determining a target IoT noise value for each RBM, determining a total path loss from each RBM to its serving hub, determining a target uplink carrier to interference and noise ratio (CINR) for the RBM, and computing the RBM uplink transmit power for each RBM by summing the target IoT noise value for the RBM, the total path loss of the RBM to its serving hub, and the target uplink CINR. Computationally expensive parameter sweeps are avoided. The method can be implemented using a centralized processing unit or distributed processing at each node. The method is self-optimizing, and initial hub and RBM transmit powers and other data may be estimated using pre-deployment tools.

Abstract: A system and method for downlink power optimization in a partitioned wireless backhaul network with out-of-neighborhood utility evaluation is disclosed. The method comprises performing initial downlink power optimization for each neighborhood independently, considering only in-neighborhood utilities, by obtaining the transmit powers of all hubs and a utility performance of all served remote backhaul modules (RBMs) in the neighborhood. Power optimization data for each neighborhood are then reported to a central processing unit for storage. Thereafter, for each neighborhood, an out-of-neighborhood utility evaluation is performed by the centralized processing unit, based on reported power optimization data from other neighborhoods, for example, by obtaining delta out-of-neighborhood sum utilities for each hub as a function of hub transmit power, by curve fitting of reported data.

Abstract: Systems, methods and apparatuses are provided for mitigating interference in wireless networks, and particularly in an advanced backhaul wireless network comprising several hubs, each hub serving its own remote backhaul modules (RBMs). Preferred embodiments provide practical power spectrum adaptation methods for the management of interhub interference. These methods are shown to improve the overall network throughput significantly compared to a conventional network with fixed transmit power spectrum. Optionally, joint scheduling and power control are used to optimize the network utility. Also provided are methods which evoke the channel average gains generated by measurements for managed adaptive resource allocation (MARA). The proposed methods are computationally feasible and fast in convergence. They can be implemented in a distributed fashion across all hubs. Some of the proposed methods can be implemented asynchronously at each hub.

Abstract: Methods are disclosed for scheduling resources in a wireless backhaul network comprising a plurality of N Hubs, each Hub serving a plurality of K Remote Backhaul Modules (RBMs), using a coordinated power zone assignment across the backhaul network. For each Hub, a one-to-one power zone assignment, of each of the K RBM to one of the K power zones, is computed by maximizing a selected network utility across the backhaul network. Coordinated power zone assignment according to preferred embodiments based on the auction approach offers a close-to-global-optimal solution. Coordinated scheduling based on first assigning RBMs to hubs heuristically, and then optimally scheduling RBMs within each hub also offers significant performance improvement as compared to non-coordinated systems. Preferred embodiments offer a significant performance improvement as compared to conventional systems.

Abstract: Practical methods and apparatuses are provided for determining network clusters in wireless backhaul networks comprising a plurality of hubs and Remote Backhaul Modules (RBM) (104) based on link quality value (LQV) metrics. From an input LQV table of LQV values for each hub-RBM link (110), the link quality values are first ranked. Clusters are then identified from all the possible links based on the order of the highest link quality value to the lowest link quality value, any constraints on the number of RBMs per cluster, and clustering each RBM only once. Links with strong link quality values are chosen to optimize the LQV metric. LQV based clustering achieves a higher average LQV, e.g., average spectrum efficiency or weighted sum spectrum efficiency, for the entire backhaul network compared to the geographic location based clustering. The method is straightforward to implement and has low computational complexity.

Abstract: A method and system is disclosed for managing performance of a wireless backhaul network through power management, which provides a practical approach to balancing data throughput and fairness. For each transmit frame, one or more power zones is defined, each power zone comprising a set of radio resources operating at one transmit power level Pi, and the same power zone being defined over the same set of radio resources across all other clusters. The method maximizes the value of weighted weighted-sum utility, using a rate expression based on a CINR function. The optimization comprises a summation of the weighted logarithm of the rate expression plus a non-negative constant value, using a Newton's method approach, for fast and reliable convergence. Optimization may be based on long term averaged channel gains measured for each link. The value of c is selected to achieve a required balance of fairness and data throughput.

Abstract: Methods and apparatus are provided for managing interference in a wireless backhaul network comprising a plurality of hubs, each hub serving a plurality of remote backhaul modules (RBM), using power control with a one-power-zone (OPZ) constraint. Each hub uses a transmit frame structure comprising a plurality of zones, each RBM is scheduled on a different zone, and the same power level is maintained across all zones within a transmit frame. Under the OPZ constraint, and for scheduling policies under which the number of zones assigned to each RBM is fixed, the power and scheduling sub-problems are decoupled. This enables power control independent of scheduling, using methods having lower computational complexity. Methods are disclosed comprising iterative function evaluation or Newton's method approaches based on a weighted sum-rate maximization across the network, which can be implemented in a distributed fashion. Some of the methods can be implemented asynchronously at each hub.

Abstract: Systems, methods and apparatuses are provided for mitigating interference in wireless networks, and particularly in an advanced backhaul wireless network comprising several hubs, each hub serving its own remote backhaul modules (RBMs). Preferred embodiments provide practical power spectrum adaptation methods for the management of interhub interference. These methods are shown to improve the overall network throughput significantly compared to a conventional network with fixed transmit power spectrum. Optionally, joint scheduling and power control are used to optimize the network utility. Also provided are methods which evoke the channel average gains generated by measurements for managed adaptive resource allocation (MARA). The proposed methods are computationally feasible and fast in convergence. They can be implemented in a distributed fashion across all hubs. Some of the proposed methods can be implemented asynchronously at each hub.

Abstract: A multiple antenna system for using a relay station with multiple antennas is provided. The system includes a base station for determining encoded data processing procedure based on first and second channel state information, determining a relaying procedure of the relay station, and sending the relaying procedure to the relay station based on the first and second channel state information; wherein the encoded data is terminating to a mobile station; the relay station for receiving data and the relay procedure which the base station sent, converting and sending the data according to the relaying procedure, and sending the first channel state information to the base station as a measured state of channel which receives the data; and the mobile station for receiving the data which the relay station sent, and sending the second channel state information to the relay station as a measured state of channel which receives the data.

Abstract: In an adaptive feedback method for a cellular communication system having plural terminals feeding back channel information to an access point, the system selects one of an opportunistic mode and a polling mode as a feedback mode between an access point and the terminals on the basis of system and traffic parameters, sets up the access point and the terminals for the selected feedback mode, and feeds back the channel information from the terminals to the access point in the selected feedback mode. The adaptive feedback method changes the feedback mechanism adaptively to the system and traffic environment, making it possible to increase the system throughput as well as to decrease the MAC overhead regardless of the variation of the number of MSs.

Abstract: A multiple antenna system for using a relay station with multiple antennas is provided. The system includes a base station for determining encoded data processing procedure based on first and second channel state information, determining a relaying procedure of the relay station, and sending the relaying procedure to the relay station based on the first and second channel state information; wherein the encoded data is terminating to a mobile station; the relay station for receiving data and the relay procedure which the base station sent, converting and sending the data according to the relaying procedure, and sending the first channel state information to the base station as a measured state of channel which receives the data; and the mobile station for receiving the data which the relay station sent, and sending the second channel state information to the relay station as a measured state of channel which receives the data.

Abstract: In an adaptive feedback method for a cellular communication system having plural terminals feeding back channel information to an access point, the system selects one of an opportunistic mode and a polling mode as a feedback mode between an access point and the terminals on the basis of system and traffic parameters, sets up the access point and the terminals for the selected feedback mode, and feeds back the channel information from the terminals to the access point in the selected feedback mode. The adaptive feedback method changes the feedback mechanism adaptively to the system and traffic environment, making it possible to increase the system throughput as well as to decrease the MAC overhead regardless of the variation of the number of MSs.