Abstract: Systems and methods are disclosed for networking planning for fixed backhaul networks comprising a plurality of hubs, each serving one or more RBMs. The method comprises one or more of terrain pathloss (PL) and antenna gain prediction; network design comprising site association, hub dimensioning and pointing; and optimization of small cell (SC) deployment. PL prediction is based on correlation of user input parameters with reference use cases for channel models for each of downtown, urban, and suburban deployment scenarios. Rapid and effective network planning is achieved with limited input data, even in the absence of high resolution digital maps or building polygons, by selecting the channel model having a highest correlation with available environmental parameters. Optimization of network topology design, system design, and SC deployment, with both access link and backhaul link evaluation, is based on optimization of a sum-utility function across all links for feasible SC site locations.

Abstract: Systems and methods are disclosed for signaling in a point-to-multi-point (PtMP) fixed wireless backhaul network, in which each Hub serves a plurality of Remote Backhaul Modules (RBM). A Hub serves one RBM in each subframe per carrier in TDMA fashion, comprising transmitting a 1 ms TDD frame comprising one DL subframe and one UL subframe and gaps necessary to switch the radio direction and accommodate round trip delay. DL and UL frames may be allocated to different RBMs, with a single RBM in each DL or UL subframe per carrier per antenna beam. Each Hub keeps an independent context for each of its served RBMs. A DL ranging frame carries general information. A UL ranging frame carries a ranging opportunity. RBMs not scheduled in the current timeslot continue to receive a PHY control channel from the serving Hub, and update their parameters or links for link adaptation.

Abstract: A system and method for joint scheduling in a dual-carrier fixed wireless backhaul network is disclosed, wherein the primary carrier is a licensed band, and the secondary carrier is a lower cost shared band or an unlicensed band. The network comprises a plurality of Hub modules, each serving a cluster of one or more Remote backhaul modules (RBMs). A special frame structure and a control channel on the primary carrier carries control signalling messages for RBMs assigned to either the primary or secondary carrier. RBMs with a performance metric, such a spectral efficiency, above a threshold are assigned to the primary carrier. Other RBMs are assigned the secondary carrier, and a channel assignment is then performed. A transmission mode is determined based on instantaneous channel conditions, to optimize overall system performance across a network neighborhood and meet RBM quality of service requirements. A centralized server/processing unit co-ordinates dual carrier joint scheduling functions.

Abstract: A method and system is disclosed for clock synchronization in a wireless backhaul network, based on the IEEE1588 Precision Time Protocol (PTP). The network comprises a plurality of hubs, each hub serving one or more remote backhaul modules. Each hub comprises a slave clock, which communicates with a master clock through forward and reverse links. The method comprises, for each hub, estimating the frequency drift {circumflex over (?)} and offset {circumflex over (?)} from the forward and reverse links between the master and slave clock, estimating the accuracy of {circumflex over (?)} and {circumflex over (?)}, determining the least congested link, and adjusting the frequency of the slave clock based on {circumflex over (?)} and {circumflex over (?)} from the least congested link. A fixed or variable time window size is selected to achieve a desired accuracy of {circumflex over (?)} and {circumflex over (?)}.

Abstract: A system and method for joint scheduling in a dual-carrier fixed wireless backhaul network is disclosed, wherein the primary carrier is a licensed band, and the secondary carrier is a lower cost shared band or an unlicensed band. The network comprises a plurality of Hub modules, each serving a cluster of one or more Remote backhaul modules (RBMs). A special frame structure and a control channel on the primary carrier carries control signalling messages for RBMs assigned to either the primary or secondary carrier. RBMs with a performance metric, such a spectral efficiency, above a threshold are assigned to the primary carrier. Other RBMs are assigned the secondary carrier, and a channel assignment is then performed. A transmission mode is determined based on instantaneous channel conditions, to optimize overall system performance across a network neighbourhood and meet RBM quality of service requirements. A centralized server/processing unit co-ordinates dual carrier joint scheduling functions.

Abstract: A system and method for reception mode switching in a dual-carrier fixed wireless backhaul network is disclosed. The primary carrier is a licensed band. The secondary carrier may be a lower cost shared band or an unlicensed band. Multi-mode Remote Backhaul Modules (RBMs) comprise a first Radio Frequency (RF) chain with antenna elements for receive/transmit (RX/TX) on the primary carrier and a second RF chain with antenna elements for RX/TX on the secondary carrier. The Multi-mode RBMs adaptively switch from one reception mode to another with resource borrowing of RF and antenna elements, e.g. the secondary carrier RF chain and antenna elements can be borrowed for the primary carrier, for better reception capability for the primary carrier, reducing the number of link-budget and interference-challenged RBMs, and improving system performance.

Abstract: A system and method for joint scheduling in a dual-carrier fixed wireless backhaul network is disclosed, wherein the primary carrier is a licensed band, and the secondary carrier is an unlicensed or lower cost shared carrier. The network comprises a plurality of Hub modules, each serving a cluster of one or more Remote backhaul modules (RBMs). A special frame structure and a control channel on the primary carrier carries control signalling messages for RBMs assigned to either the primary or secondary carrier. RBMs with a performance metric, such a spectral efficiency, above a threshold are assigned to the primary carrier. Other RBMs are assigned the secondary carrier, and a channel assignment is then performed. A transmission mode is determined based on instantaneous channel conditions, to optimize overall system performance across a network neighborhood and meet RBM quality of service requirements. A centralized server/processing unit coordinates dual carrier joint scheduling functions.

Abstract: Practical methods and apparatuses are provided for determining network clusters in wireless backhaul networks comprising a plurality of hubs (102) 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: Systems and methods are disclosed for coordinating hub-beam selection in wireless backhaul networks and optionally, for joint hub-beam selection and slot assignment. Data indicative of path loss is measured or estimated for each of a set of RBMs and for each hub-beam of a respective multi-beam serving hub. A performance metric is computed, and hub-beam selection is made based on optimizing the performance metric across the set of RBMs. A serving hub may use reserved frames to train an RBM on each hub-beam and communicate beam selections, e.g. based on minimizing path loss on a per-cell or per-sector basis, or maximizing a sum-utility function for improved performance over a neighborhood of the network. A beam assignment map may be shared amongst serving hubs. A weight table of good and bad beam combinations may be generated to evaluate the cost of a hub-beam combination, for joint hub-beam selection and slot assignment.

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: 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: 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: 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: 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 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: A system, method, and software are provided for measuring co-channel interference comprising interlink interference in a wireless backhaul network with particular application for management of resource allocation for Non Line of Sight (NLOS) wireless backhaul in MicroCell and PicoCell networks. Given the difficulty of predicting the interlink interference between multiple links, DownLink and UpLink co-channel interference are characterized for each backhaul radio link between each Hub and each Remote Backhaul Module Unit periodically during active service. Beneficially, the co-channel interference metrics are used as the basis for intelligently and adaptively managing network resources to substantially reduce cumulative interference and increase the aggregate data capacity of the network e.g. by grouping of interfering and/or non-interfering links, and managing resource block allocations accordingly, i.e.

Abstract: An antenna arrangement, a system, and method are provided for implementing a wireless communication module capable of performing adaptive beam forming, with a small antenna sail area. The antenna has a large horizontal to vertical aspect ratio. The antenna module is designed to include very few, or potentially a single radiating element in the vertical direction, and many elements in the horizontal direction, in order to create narrow beam in the azimuth plane, while maintaining a small sail area. The novel form factor advantageously provides for reduced wind loading, and for less conspicuous installations on buildings or towers, for example. The module is anticipated to find widespread applications in LOS and NLOS backhaul applications, and other wireless links between stationary nodes.