# US 11,115,897 B2 · Energy-efficient multi-hop communication schemes for wireless networks > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,115,897 B2 - Document ID: US11115897B2 - Status: Granted - Kind: B2 - Application number: 15/564,376 - Filed: 2016-04-14 - Published: 2018-05-17 - Granted: 2021-09-07 - Earliest claimed: 2015-04-15 - Assignees: Telefonaktiebolaget LM Ericsson (publ) - Applicants: Telefonaktiebolaget LM Ericsson (publ) - Inventors: Dennis Hui; Songnam Hong; Ivana Maric - Web page: https://patentgrep.com/patent/US11115897B2 ## CPC - H04W 40/16: based on interference - H04L 45/021: Ensuring consistency of routing table updates, e.g. by using epoch numbers - H04L 45/122: by minimising distances, e.g. by selecting a route with minimum of number of hops - H04L 45/123: {Evaluation of link metrics (techniques for monitoring network metrics H04L43/08)} - H04L 45/127: {based on intermediate node capabilities} - H04L 45/16: Multipoint routing - Y02D 30/70: in wireless communication networks - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - Y02D: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE ## Abstract A method in a node is disclosed. The method comprises determining (1304) a first route from a first source node (505 A) to a destination (510), the first route comprising one or more relay nodes (515, 615). The method comprises determining (1308) an energy-harvesting routing metric, the energy-harvesting routing metric for use in determining a second route from a second source node (505B) to the destination (510). The method comprises determining (1312) the second route from the second source node (505B) to the destination (510), the determined second route comprising one or more relay nodes (515, 615) selected to maximize the determined energy-harvesting routing metric. ## Claims ### Claim 1 A method in a node, comprising: determining a first route from a first source node to a destination, the first route comprising one or more relay nodes; determining an energy-harvesting routing metric, the energy-harvesting routing metric for use in determining a second route from a second source node to the destination; determining the second route from the second source node to the destination, the determined second route comprising one or more relay nodes selected to maximize the determined energy-harvesting routing metric; transmitting at least a portion of the second route to one or more of the second source node and the one or more relay nodes for use by the second source node to transmit data to the destination; and wherein determining the second route from the second source node to the destination comprises: determining one or more first candidate relay nodes, the first candidate relay nodes located within a communication range of the second source node; determining which of the one or more first candidate relay nodes maximizes the energy-harvesting routing metric, wherein the determination of which of the one or more first candidate relay nodes maximizes the energy-harvesting routing metric is based on an energy-harvesting routing metric of the first source node, the second source node, and a first relay node of the first route; and selecting a first candidate relay node that maximizes the energy-harvesting routing metric as the first relay node of the second route. ### Claim 2 (depends on 1) The method of claim 1, wherein the determined first route comprises a route having a shortest number of hops between the first source node and the destination. ### Claim 3 (depends on 1) The method of claim 1, comprising: determining one or more second candidate relay nodes, the second candidate relay nodes located within a communication range of the selected first relay node of the second route; determining which of the one or more second candidate relay nodes maximizes the energy-harvesting routing metric, wherein the determination of which of the one or more second candidate relay nodes maximizes the energy-harvesting routing metric is based on an energy-harvesting routing metric of the first relay node of the first route, the first relay node of the second route, and a second relay node of the first route; and selecting a second candidate relay node that maximizes the energy-harvesting routing metric as the second relay node of the second route. ### Claim 4 (depends on 1) The method of claim 1, comprising: optimizing the determined first route based on the determined second route, the second route comprising one or more relay nodes selected according to the determined energy-harvesting routing metric, wherein the optimized first route maximizes the energy-harvesting routing metric. ### Claim 5 (depends on 4) The method of claim 4, wherein optimizing the determined first route based on the determined second route comprises: determining one or more third candidate relay nodes, the third candidate relay nodes located within a communication range of the first source node; determining which of the one or more third candidate relay nodes maximizes the energy-harvesting routing metric, wherein the determination of which of the one or more third candidate relay nodes maximizes the energy-harvesting routing metric is based on an energy-harvesting routing metric of the first source node, the second source node, and a first relay node of the second route; and selecting a third candidate relay node that maximizes the energy-harvesting routing metric as a new first relay node of the first route. ### Claim 6 (depends on 5) The method of claim 5, comprising: determining one or more fourth candidate relay nodes, the fourth candidate relay nodes located within a communication range of the new first relay node of the first route; determining which of the one or more fourth candidate relay nodes maximizes the energy-harvesting routing metric, wherein the determination of which of the one or more fourth candidate relay nodes maximizes the energy-harvesting routing metric is based on an energy-harvesting routing metric of the new first relay node of the first route, the first relay node of the second route, and the second relay node of the second route; and selecting a fourth candidate relay node that maximizes the energy-harvesting routing metric as a new second relay node of the first route. ### Claim 7 (depends on 4) The method of claim 4, comprising: optimizing the determined second route based on the optimized first route, wherein the optimized second route maximizes the energy-harvesting routing metric. ### Claim 8 (depends on 7) The method of claim 7, comprising: continuing to optimize the determined first and second routes until the energy-harvesting routing metric for both the first and second routes exceeds a threshold value. ### Claim 9 (depends on 1) The method of claim 1, wherein maximizing the energy-harvesting routing metric comprises maximizing an achievable rate between consecutive relay nodes. ### Claim 10 (depends on 1) The method of claim 1, wherein the energy-harvesting routing metric comprises a multiple input multiple output (MIMO) channel capacity. ### Claim 11 (depends on 1) The method of claim 1, wherein the energy-harvesting routing metric is a function of a signal-to-noise ratio. ### Claim 12 (depends on 1) The method of claim 1, wherein maximizing the energy-harvesting routing metric comprises maximizing interference between routes. ### Claim 13 (depends on 1) The method of claim 1, wherein the relay nodes perform noisy network coding. ### Claim 14 (depends on 1) The method of claim 1, comprising: defining a plurality of subnetworks, the defined plurality of subnetworks comprising at least a first subnetwork comprising the destination and the first and second source nodes and a second subnetwork comprising a second destination and a plurality of source nodes associated with the second destination, the plurality of source nodes including at least one additional source node; determining a first route for the second subnetwork from one of the plurality of source nodes associated with the second destination to the second destination, the first route for the second subnetwork comprising one or more relay nodes; determining a second route for the second subnetwork from another of the plurality of source nodes associated with the second destination to the second destination, the determined second route for the second subnetwork comprising one or more relay nodes selected to maximize the determined energy-harvesting routing metric; and optimizing the determined first route for the second subnetwork based on the determined second route for the second subnetwork, the second route for the second subnetwork comprising one or more relay nodes selected according to the determined energy-harvesting routing metric, wherein the optimized first route for the second subnetwork maximizes the energy-harvesting routing metric. ### Claim 15 (depends on 14) The method of claim 14, wherein the first route for the second subnetwork is determined using interference-aware routing. ### Claim 16 (depends on 1) The method of claim 1, wherein the first route and the second route comprise different numbers of relay nodes. ### Claim 17 A node, comprising: one or more processors, the one or more processors configured to: determine a first route from a first source node to a destination, the first route comprising one or more relay nodes; determine an energy-harvesting routing metric, the energy-harvesting routing metric for use in determining a second route from a second source node to the destination; determine the second route from the second source node to the destination, the determined second route comprising one or more relay nodes selected to maximize the determined energy-harvesting routing metric; transmit at least a portion of the second route to one or more of the second source node and the one or more relay nodes for use by the second source node to transmit data to the destination; and wherein the one or more processors configured to determine the second route from the second source node to the destination comprise one or more processors configured to: determine one or more first candidate relay nodes, the first candidate relay nodes located within a communication range of the second source node; determine which of the one or more first candidate relay nodes maximizes the energy-harvesting routing metric, wherein the determination of which of the one or more first candidate relay nodes maximizes the energy-harvesting routing metric is based on an energy-harvesting routing metric of the first source node, the second source node, and a first relay node of the first route; and select a first candidate relay node that maximizes the energy-harvesting routing metric as the first relay node of the second route. ### Claim 18 (depends on 17) The node of claim 17, wherein the determined first route comprises a route having a shortest number of hops between the first source node and the destination. ### Claim 19 (depends on 17) The node of claim 17, wherein the one or more processors are further configured to: determine one or more second candidate relay nodes, the second candidate relay nodes located within a communication range of the selected first relay node of the second route; determine which of the one or more second candidate relay nodes maximizes the energy-harvesting routing metric, wherein the determination of which of the one or more second candidate relay nodes maximizes the energy-harvesting routing metric is based on an energy-harvesting routing metric of the first relay node of the first route, the first relay node of the second route, and a second relay node of the first route; and select a second candidate relay node that maximizes the energy-harvesting routing metric as the second relay node of the second route. ### Claim 20 (depends on 17) The node of claim 17, wherein the one or more processors are further configured to: optimize the determined first route based on the determined second route, the second route comprising one or more relay nodes selected according to the determined energy-harvesting routing metric, wherein the optimized first route maximizes the energy-harvesting routing metric. ### Claim 21 (depends on 20) The node of claim 20, wherein the one or more processors configured to optimize the determined first route based on the determined second route comprise one or more processors configured to: determine one or more third candidate relay nodes, the third candidate relay nodes located within a communication range of the first source node; determine which of the one or more third candidate relay nodes maximizes the energy-harvesting routing metric, wherein the determination of which of the one or more third candidate relay nodes maximizes the energy-harvesting routing metric is based on an energy-harvesting routing metric of the first source node, the second source node, and a first relay node of the second route; and select a third candidate relay node that maximizes the energy-harvesting routing metric as a new first relay node of the first route. ### Claim 22 (depends on 21) The node of claim 21, wherein the one or more processors are further configured to: determine one or more fourth candidate relay nodes, the fourth candidate relay nodes located within a communication range of the new first relay node of the first route; determine which of the one or more fourth candidate relay nodes maximizes the energy-harvesting routing metric, wherein the determination of which of the one or more fourth candidate relay nodes maximizes the energy-harvesting routing metric is based on an energy-harvesting routing metric of the new first relay node of the first route, the first relay node of the second route, and the second relay node of the second route; and select a fourth candidate relay node that maximizes the energy-harvesting routing metric as a new second relay node of the first route. ### Claim 23 (depends on 20) The node of claim 20, wherein the one or more processors are further configured to: optimize the determined second route based on the optimized first route, wherein the optimized second route maximizes the energy-harvesting routing metric. ### Claim 24 (depends on 23) The node of claim 23, wherein the one or more processors are further configured to: continue to optimize the determined first and second routes until the energy-harvesting routing metric for both the first and second routes exceeds a threshold value. ### Claim 25 (depends on 17) The node of claim 17, wherein maximizing the energy-harvesting routing metric comprises maximizing an achievable rate between consecutive relay nodes. ### Claim 26 (depends on 17) The node of claim 17, wherein the energy-harvesting routing metric comprises a multiple input multiple output (MIMO) channel capacity. ### Claim 27 (depends on 17) The node of claim 17, wherein the energy-harvesting routing metric is a function of a signal-to-noise ratio. ### Claim 28 (depends on 17) The node of claim 17, wherein the one or more processors are configured to maximize the energy-harvesting routing metric by maximizing interference between routes. ### Claim 29 (depends on 17) The node of claim 17, wherein the relay nodes perform noisy network coding. ### Claim 30 (depends on 17) The node of claim 17, wherein the one or more processors are further configured to: define a plurality of subnetworks, the defined plurality of subnetworks comprising at least a first subnetwork comprising the destination and the first and second source nodes and a second subnetwork comprising a second destination and a plurality of source nodes associated with the second destination, the plurality of source nodes including at least one additional source node; determine a first route for the second subnetwork from one of the plurality of source nodes associated with the second destination to the second destination, the first route for the second subnetwork comprising one or more relay nodes; determine a second route for the second subnetwork from another of the plurality of source nodes associated with the second destination to the second destination, the determined second route for the second subnetwork comprising one or more relay nodes selected to maximize the determined energy-harvesting routing metric; and optimize the determined first route for the second subnetwork based on the determined second route for the second subnetwork, the second route for the second subnetwork comprising one or more relay nodes selected according to the determined energy-harvesting routing metric, wherein the optimized first route for the second subnetwork maximizes the energy-harvesting routing metric. ### Claim 31 (depends on 30) The node of claim 30, wherein the first route for the second subnetwork is determined using interference-aware routing. ### Claim 32 (depends on 17) The node of claim 17, wherein the first route and the second route comprise different numbers of relay nodes. ### Claim 33 A computer program product comprising instructions stored on non-transient computer-readable media which, when executed by one or more processors, perform the acts of: determining a first route from a first source node to a destination, the first route comprising one or more relay nodes; determining an energy-harvesting routing metric, the energy-harvesting routing metric for use in determining a second route from a second source node to the destination; determining the second route from the second source node to the destination, the determined second route comprising one or more relay nodes selected to maximize the determined energy-harvesting routing metric; transmitting at least a portion of the second route to one or more of the second source node and the one or more relay nodes for use by the second source node to transmit data to the destination; and wherein determining the second route from the second source node to the destination comprises: determining one or more first candidate relay nodes, the first candidate relay nodes located within a communication range of the second source node; determining which of the one or more first candidate relay nodes maximizes the energy-harvesting routing metric, wherein the determination of which of the one or more first candidate relay nodes maximizes the energy-harvesting routing metric is based on energy-harvesting routing metrics of the first source node, the second source node, and a first relay node of the first route; and selecting a first candidate relay node that maximizes the energy-harvesting routing metric as the first relay node of the second route.