# US 8,787,195 B2 · Beacon selection in communication networks > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,787,195 B2 - Document ID: US8787195B2 - Status: Granted - Kind: B2 - Application number: 13/531,324 - Filed: 2012-06-22 - Published: 2012-11-22 - Granted: 2014-07-22 - Earliest claimed: 2011-06-29 - Assignees: Texas Instruments Incorporated - Applicants: Kumaran Vijayasankar; Ramanuja Vedantham; Robert Liang; Susan Yim; Xiaolin Lu - Inventors: Kumaran Vijayasankar; Ramanuja Vedantham; Robert Liang; Susan Yim; Xiaolin Lu - Web page: https://patentgrep.com/patent/US8787195B2 ## CPC - H04B 3/542: {the information being in digital form} - H04L 5/0007: {the frequencies being orthogonal, e.g. OFDM(A) or DMT} - H04L 25/0264: {Arrangements for coupling to transmission lines (duplexing arrangements H04L5/14; line equalisers, line build-out devices H04L25/03878)} - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Systems and methods for beacon selection in communication networks are described. In various implementations, these systems and methods may be applicable to Power Line Communications (PLC). For example, a method may include performing, using a terminal device deployed in a communications network, receiving a beacon transmitted by a switch device within the communications network and, in response to the terminal device having had a previous connection with the switch device, determining a connection time of the previous connection. The method may also include performing at least one of: adding the switch device to a blacklist in response to the connection time being smaller than a first threshold value, or selecting the switch device for subsequent communication in response to the connection time being greater than a second threshold value. ## Claims ### Claim 1 A method comprising: performing, using a terminal device deployed in a communications network, receiving a beacon transmitted by a switch device within in the communications network; in response to the terminal device having had a previous connection with the switch device, determining a connection time of the previous connection; adding the switch device to a blacklist in response to the connection time being smaller than a first threshold value or selecting the switch device for subsequent communication in response to the connection time being greater than a second threshold value; determining a signal quality indicator of the beacon in response to the connection time being between the first and second threshold values; and storing an entry corresponding to the beacon in a first portion of a preferences list in response to the signal quality indicator being greater than a signal quality threshold value or storing an entry corresponding to the beacon in a second portion of the preferences list in response to the signal quality indicator being smaller than the signal quality threshold value. ### Claim 2 (depends on 1) The method of claim 1, wherein the communications network is a Power Line Communications (PLC) network. ### Claim 3 (depends on 1) The method of claim 1, further comprising: performing, using the terminal device, determining that the previous connection was terminated due to channel conditions. ### Claim 4 (depends on 3) The method of claim 3, wherein the channel conditions include a loss of beacon event or a timeout event. ### Claim 5 (depends on 1) The method of claim 1, wherein the signal quality indicator is a Signal-to-Noise (SNR) ratio. ### Claim 6 (depends on 1) The method of claim 1, wherein the first portion of the preferences list includes a plurality of entries corresponding to other beacons transmitted by other switch devices within the communications network, the plurality of entries ordered according to their respective beacon's signal level. ### Claim 7 (depends on 1) The method of claim 1, wherein the first portion of the preferences list includes a plurality of entries corresponding to other beacons transmitted by other switch devices within the communications network, the plurality of entries ordered according to a received signal strength of the beacon between the terminal device and each switch device corresponding to a respective entry. ### Claim 8 (depends on 1) The method of claim 1, wherein the second portion of the preferences list includes a plurality of entries corresponding to other beacons transmitted by other switch devices within the communications network, the plurality of entries ordered by their respective beacon's signal quality indicators. ### Claim 9 (depends on 1) The method of claim 1, further comprising: performing, using the terminal device: selecting one of a plurality of switch devices for a subsequent communication based upon a plurality of ordered entries in the first portion of the preferences list or selecting one of a plurality of switch devices for a subsequent communication based upon a plurality of ordered entries in the second portion of the preferences list in response to no entries being stored in the first portion of the preferences list. ### Claim 10 A method comprising: performing, using a terminal device deployed in a communications network, receiving a beacon transmitted by a switch device within in the communications network; in response to the terminal device having had a previous connection with the switch device, determining a connection time of the previous connection; adding the switch device to a blacklist in response to the connection time being smaller than a first threshold value or selecting the switch device for subsequent communication in response to the connection time being greater than a second threshold value; determining a signal quality indicator of the beacon in response to the connection time being between the first and second threshold values; and storing an entry corresponding to the beacon in a first plurality of entries in a last portion of a preferences list in response to the signal quality indicator being smaller than a signal quality threshold value, each of the last plurality of entries in the last portion of the preferences list ordered by their respective signal quality indicators, or determining a beacon quality index for the beacon and storing an entry corresponding to the beacon in an nth plurality of entries in an nth portion of the preferences list in response to the beacon quality index being greater than or equal to an nth predetermined value, each of the n portions of the preferences list having their respective entries from the nth plurality of entries ordered by their respective signal levels, wherein n is an integer greater than 1. ### Claim 11 (depends on 10) The method of claim 10, wherein determining the beacon quality index includes determining an end-to-end probability of success in communications between the terminal device and the switch device, and mapping a calculated end-to-end probability of success to one of a plurality of possible beacon quality indexes. ### Claim 12 (depends on 10) The method of claim 10, further comprising: performing, using the terminal device, selecting one of a plurality of switch devices for a subsequent communication by sequentially inspecting one or more of the portions of the preferences list. ### Claim 13 A system, comprising: a communications device having a processor and a memory coupled to the processor, the memory configured to store program instructions executable by the processor to cause the communications device to: identify a beacon associated with a switch node in a communications network; in response to the communications device having had a previous connection with the switch node, determine a connection time of the previous connection; determine a signal quality indicator of the beacon in response to the connection time being between a first threshold value and a second threshold value; store an entry corresponding to the beacon in a first portion of a preferences list in response to the signal quality indicator being greater than a signal quality threshold value; and store an entry corresponding to the beacon in a second portion of the preferences list in response to the signal quality indicator being smaller than the signal quality threshold value. ### Claim 14 (depends on 13) The system of claim 13, wherein the signal quality indicator is a Signal-to-Noise (SNR) ratio. ### Claim 15 (depends on 14) The system of claim 14, wherein the first portion of the preferences list includes a first plurality of entries corresponding to other beacons transmitted by other switch nodes, the first plurality of entries ordered according to their respective beacon's signal level, and wherein the second portion of the preferences list includes a second plurality of entries corresponding to other beacons transmitted by other switch nodes, the second plurality of entries ordered by their respective beacon's signal quality indicators. ### Claim 16 (depends on 15) The system of claim 15, the program instructions further executable by the processor to cause the communications device to select one of a plurality of switch nodes for a subsequent communication based upon the first plurality of entries in the first portion of the preferences list, if any, followed by the second plurality of entries in the second portion of the preferences list if no entries are stored in the first portion of the preferences list. ### Claim 17 A non-transitory electronic storage medium having program instructions stored thereon that, upon execution by a processor within a communications device, cause the communications device to: identify a beacon associated with a switch node in a communications network; in response to the communications device having had a previous connection with the switch node, determine a connection time of the previous connection; determine a signal quality indicator of the beacon in response to the connection time being between a first threshold value and a second threshold value; store an entry corresponding to the beacon in a plurality of entries in a last portion of a preferences list in response to the signal quality indicator being smaller than a signal quality threshold value, each of the plurality of entries in the last portion of the preferences list ordered by their respective signal quality indicators; and determine a beacon quality index for the beacon and storing an entry corresponding to the beacon in an nth portion of the preferences list in response to the beacon quality index being greater than or equal to an nth predetermined value, each of the n portions of the preferences list having their plurality of entries ordered by their respective signal levels, wherein n is an integer greater than 1. ### Claim 18 (depends on 17) The electronic storage medium of claim 17, wherein to determine the beacon quality index, the program instructions, upon execution by the processor, further cause the communications device to determine an end-to-end probability of success in communications between the communications device and the switch device, and mapping a calculated end-to-end probability of success to one of a plurality of possible beacon quality indexes. ### Claim 19 (depends on 18) The electronic storage medium of claim 18, wherein the program instructions, upon execution by the processor, further cause the communications device to select one of a plurality of switch devices for a subsequent communication by sequentially inspecting one or more of the n+1 portions of the preferences list in order.