# US 9,438,309 B2 · Asymmetric channels in power line communications > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,438,309 B2 - Document ID: US9438309B2 - Status: Granted - Kind: B2 - Application number: 14/990,471 - Filed: 2016-01-07 - Published: 2016-04-28 - Granted: 2016-09-06 - Earliest claimed: 2012-12-17 - Assignees: Texas Instruments Incorporated - Applicants: Texas Instruments Incorporated - Inventors: Kumaran Vijayasankar; Ramanuja Vedantham; Il Han Kim - Web page: https://patentgrep.com/patent/US9438309B2 ## CPC - H04B 3/54: Systems for transmission via power distribution lines - H04B 3/46: Monitoring; Testing - H04B 3/542: {the information being in digital form} - H04B 2203/5495: having measurements and testing channel - H04B: TRANSMISSION ## Abstract Apparatus (and related methods) for a power line communication network include a processor configured to receive beacons over a communication interface. The processor determines a link quality indicator (LQI) for each received beacon and ignores the beacons for at most a predetermined maximum number of beacon receptions when each LQI is below a threshold. The processor responds to a received beacon if the LQI for such received beacon exceeds the threshold or if a predetermined maximum number of beacons have been received with LQIs below the threshold. ## Claims ### Claim 1 An apparatus for a power line communication (PLC) network, comprising: an interface configured to receive a PLC signal from the PLC network; and a PLC engine coupled to the interface, the PLC engine configured to: extract beacons from the received PLC signal; determine a link quality based on the beacons; ignore the beacons for at most a predetermined number of beacon reception when the link quality is determined to be below a threshold; and respond to one or more of the received beacons if either the link quality associated with the received beacons exceeds the threshold or the predetermined number of beacon reception have been received with the link quality determined to be below the threshold. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the PLC engine is configured to increment a counter for each of the beacons with the link quality determined to be below the threshold. ### Claim 3 (depends on 2) The apparatus of claim 2, wherein the PLC engine is configured to respond to the beacons when the counter has reached a maximum count value. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the PLC engine is configured to determine the link quality based on a registration request received from a lower level node and ignore the registration request if the link quality associated with the registration request is below the threshold. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the PLC engine is configured to continuously ignore the registration request associated with which the link quality is below the threshold until a predetermined number of registration requests is received. ### Claim 6 (depends on 5) The apparatus of claim 5, wherein the PLC engine is configured to forward the registration request to a higher level node either when the respective link quality exceeds the threshold or when the predetermined number of registration requests is received. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the PLC engine is configured to determine the link quality based on a registration request received from a lower level node, and the PLC engine is configured to determine whether to ignore the registration request or to forward the registration request to a higher level node based on a probability value associated with the link quality. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the PLC engine is configured to determine the link quality based on a registration request received from a lower level node, and the PLC engine is configured to determine whether to ignore the registration request or to forward the registration request to a higher level node based on a comparison of a probability value to a registration request threshold. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein the PLC engine is configured to determine the link quality based on a promotion request received from a lower level node and ignore the promotion request if the link quality associated with the promotion request is below the threshold. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein the PLC engine is configured to continuously ignore the received promotion requests associated with which the link quality is below the threshold until a predetermined number of promotion requests is received. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the PLC engine is configured to forward the promotion request to a higher level node either when the respective link quality exceeds the threshold or when the predetermined number of promotion requests is received. ### Claim 12 (depends on 1) The apparatus of claim 1, wherein the PLC engine is configured to determine the link quality based on a promotion request received from a lower level node, and the PLC engine is configured to determine whether to ignore the promotion request or to forward the promotion request to a higher level node based on a probability value associated with the link quality. ### Claim 13 (depends on 1) The apparatus of claim 1, wherein the PLC engine is configured to determine the link quality based on a promotion request received from a lower level node, and the PLC engine is configured to determine whether to ignore the promotion request or to forward the promotion request to a higher level node based on a comparison of a probability value to a promotion request threshold. ### Claim 14 (depends on 1) The apparatus of claim 1, wherein the PLC engine is configured to ignore a Promotion Needed Protocol Data Unit (PNPDU) frame for a node to be promoted to a service node based on the link quality to or from a base node being less than the threshold. ### Claim 15 An apparatus for a power line communication (PLC) network, comprising: means for receiving beacons; means for determining a link quality for each received beacon; means for ignoring the beacons for at most a predetermined number of beacon reception when the respective link quality is below a threshold; and means for responding to one or more of the received beacons if the link quality associated with the received beacon exceeds the threshold or if the predetermined number of beacon reception is received with the link quality below the threshold. ### Claim 16 (depends on 15) The apparatus of claim 15, further comprising: means for incrementing a counter for each of the beacons with the link quality determined to be below the threshold. ### Claim 17 (depends on 15) The apparatus of claim 15, wherein: the means for determining the link quality is based on a registration request received from a lower level node; and the means for responding to one or more received beacons is configured to forward the registration request to a higher level node based on a probability value associated with the link quality. ### Claim 18 (depends on 15) The apparatus of claim 15, wherein: the means for determining the link quality is based on a registration request received from a lower level node; and the means for responding to one or more received beacons is configured to forward the registration request to a higher level node based on a comparison of a probability value to a registration request threshold. ### Claim 19 (depends on 15) The apparatus of claim 15, wherein: the means for determining the link quality is based on a promotion request received from a lower level node, and the means for responding to one or more received beacons is configured to forward the promotion request to a higher level node based on a comparison of a probability value to a promotion request threshold. ### Claim 20 (depends on 15) The apparatus of claim 15, further comprising: means for ignoring a Promotion Needed Protocol Data Unit (PNPDU) frame for a node to be promoted to a service node based on the link quality to or from a base node being less than the threshold.