# US 10,484,932 B2 · BLE networking systems and methods providing central and peripheral role reversal with enhanced peripheral location determination using ultrasonic waveform > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,484,932 B2 - Document ID: US10484932B2 - Status: Granted - Kind: B2 - Application number: 16/255,246 - Filed: 2019-01-23 - Published: 2019-05-23 - Granted: 2019-11-19 - Earliest claimed: 2017-06-17 - Assignees: Link Labs, Inc. - Applicants: Link Labs, Inc. - Inventors: Mark Bloechl; Ricardo Luna, Jr.; Patrick Li - Web page: https://patentgrep.com/patent/US10484932B2 ## CPC - H04W 48/10: using broadcasted information - H04B 11/00: Transmission systems employing ultrasonic, sonic or infrasonic waves - H04W 4/50: Service provisioning or reconfiguring - H04W 4/80: Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication - H04W 48/20: Selecting an access point - H04W 64/00: Locating users or terminals {or network equipment} for network management purposes, e.g. mobility management - H04W 84/12: WLAN [Wireless Local Area Networks] - H04W 84/18: Self-organising networks, e.g. ad-hoc networks or sensor networks - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04B: TRANSMISSION ## Abstract Provided are systems and methods for reversing the conventional roles of central and peripheral devices in a BLE network. Doing so includes implementing an end node (EN) as the sole initiator of a connection between a particular EN and a particular access point (AP). Such implementation includes determining a coordinate location of the EN based on position information for multiple reference points (RPs) and a time of flight (TOF) of an ultrasonic waveform transmitted by each of the RPs. ## Claims ### Claim 1 A BLE communications system, comprising: an end node (EN); an access point (AP) configured to connect to a network and transmit a first beacon advertisement message; and a plurality of reference points (RPs) each configured to not connect to the network and transmit each of a second beacon advertisement message comprising position information, and an ultrasonic waveform, in which the EN is configured to detect the first and second beacon advertisement messages and the ultrasonic waveform, and initiate a connection with the AP in which, as a result of the connection, the AP is caused to transfer to the network identifying information of each of the EN and the AP, wherein the detection of a respective one of the second beacon advertisement messages triggers the EN to begin the detecting of the ultrasonic waveform. ### Claim 2 (depends on 1) The BLE communications system of claim 1, wherein: the EN comprises a microphone and a timer, and the detecting of the ultrasonic waveform comprises initiating the timer upon or after receipt of the respective one of the second beacon advertisement messages to determine a time of flight (TOF) of the ultrasonic waveform. ### Claim 3 (depends on 2) The BLE communications system of claim 2, wherein: the timer is initiated after receipt of the second beacon advertisement message in accordance with a delay time defined thereby. ### Claim 4 (depends on 3) The BLE communications system of claim 3, wherein: the ultrasonic waveform is chirped, and the timer measures temporal offsets of receipt of chirps of the waveform. ### Claim 5 (depends on 2) The BLE communications system of claim 2, wherein: the ultrasonic waveform is chirped. ### Claim 6 (depends on 5) The BLE communications system of claim 5, wherein: the EN further comprises a chirped local oscillator (LO) and a mixer configured to mix chirps of the ultrasonic waveform with chirps of a signal generated by the LO. ### Claim 7 (depends on 6) The BLE communications system of claim 6, wherein: differences in frequency between respective chirps of the ultrasonic waveform and the signal generated by the LO are directly proportional to temporal offsets of receipt of the respective chirps of the ultrasonic waveform. ### Claim 8 (depends on 7) The BLE communications system of claim 7, wherein: the EN further comprises a microprocessor configured to aggregate the temporal offsets to define the TOF of the ultrasonic waveform. ### Claim 9 (depends on 8) The BLE communications system of claim 8, wherein: the microprocessor is further configured to calculate a distance to each of the plurality of RPs based on the TOF of the ultrasonic waveform transmitted therefrom. ### Claim 10 (depends on 9) The BLE communications system of claim 9, wherein: the position information comprises coordinate information, and the microprocessor is further configured to determine a position of the EN based on the calculated distances and the coordinate information. ### Claim 11 (depends on 10) The BLE communications system of claim 10, wherein: the EN transmits the determined position via the AP to the network. ### Claim 12 A BLE communications system, comprising: an end node (EN); an access point (AP) configured to connect to a network and transmit a first beacon advertisement message; and a plurality of reference points (RPs) each configured to not connect to the network and transmit each of a second beacon advertisement message comprising position information, and an ultrasonic waveform, in which the EN is configured to detect the first and second beacon advertisement messages and the ultrasonic waveform, calculate a time of flight (TOF) of the ultrasonic waveform transmitted from each of the plurality of RPs, and determine, within a coordinate system within which each of the EN, RPs and AP are operable, a coordinate position of the EN based on the TOFs, and initiate a connection with the AP in which, as a result of the connection, the AP is caused to transfer to the network identifying information of each of the EN and the AP, and the coordinate position. ### Claim 13 (depends on 12) The BLE communications system of claim 12, wherein: each ultrasonic waveform is chirped, and each TOF is based on the chirping. ### Claim 14 (depends on 13) The BLE communications system of claim 13, wherein: a detection of a respective one of the second beacon advertisement messages triggers the EN to begin the detecting of a chirp of a respective ultrasonic waveform. ### Claim 15 (depends on 14) The BLE communications system of claim 14, wherein: each TOF is based on the sum of differences between receipt times of chirps of a respective ultrasonic waveform. ### Claim 16 (depends on 15) The BLE communications system of claim 15, wherein: the coordinate position is based on distances to the RPs respectively corresponding to TOFs for each of the detected ultrasonic waveforms. ### Claim 17 (depends on 16) The BLE communications system of claim 16, wherein: the coordinate position is determined according to a least squares approach or by trilaterating, based on the distances to the RPs and the respective position information corresponding to the RPs. ### Claim 18 A method of BLE communication, comprising: executing, by one or more processors among a BLE end node (EN), a BLE access point (AP) configured to connect to a network, and a plurality of BLE reference points (RPs) configured to not connect to the network, a set of instructions for transmitting a first and a second beacon advertisement message from the AP and each of the plurality of RPs, respectively, each second beacon advertisement message comprising position information, transmitting an ultrasonic waveform from each of the plurality of RPs, detecting the first and the second beacon advertisement messages at the EN, initiating detection of at least one of the ultrasonic waveforms in response to detecting at least one of the second beacon advertisement messages, and initiating a connection between the AP and the EN, in which, as a result of the connection, the AP is caused to transfer to the network identifying information of each of the EN and the AP, and a position of the EN based on at least a pair of the ultrasonic waveforms and the position information. ### Claim 19 (depends on 18) The method of BLE communication of claim 18, further comprising: determining by the EN a time of flight (TOF) of each detected ultrasonic waveform. ### Claim 20 (depends on 19) The method of BLE communication of claim 19, wherein: each detected ultrasonic waveform is chirped. ### Claim 21 (depends on 20) The method of BLE communication of claim 20, wherein: the EN comprises a chirped local oscillator (LO) configured to generate a signal comprising a series of chirps in response to receipt of an ultrasonic waveform. ### Claim 22 (depends on 21) The method of BLE communication of claim 21, wherein: the TOF for a respective ultrasonic waveform is based on the sum of temporal offsets defined by receipt times of chirps of the ultrasonic waveform as against the generation times of chirps by the LO. ### Claim 23 (depends on 22) The method of BLE communication of claim 22, wherein: each respective ultrasonic waveform comprises a series of increasing and decreasing chirps of increasing chirp rate and decreasing duration. ### Claim 24 (depends on 23) The method of BLE communication of claim 23, wherein: the position of the EN is determined according to a least squares approach or by trilaterating, based on each of distance derived in accordance with the TOFs of respective ultrasonic waveforms and the position information corresponding to the RPs.