A method of transmitting signals from a first node having multiple transceivers to a second node is disclosed. The method comprises receiving a message from the second node at the first node, wherein the message is received by each of a plurality of transceivers of the first node; and transmitting by each of the plurality of transceivers a respective data frame to the second node in response to the message; wherein each transceiver initiates the transmission of its respective data frame a predetermined time period after receipt of the message by the transceiver; and wherein the transmissions of the data frames from the plurality of transceivers overlap. The data frames may form part of a two-way ranging exchange.

A method of transmitting signals from a first node having multiple transceivers to a second node is disclosed. The method comprises receiving a message from the second node at the first node, wherein the message is received by each of a plurality of transceivers of the first node; and transmitting by each of the plurality of transceivers a respective data frame to the second node in response to the message; wherein each transceiver initiates the transmission of its respective data frame a predetermined time period after receipt of the message by the transceiver; and wherein the transmissions of the data frames from the plurality of transceivers overlap. The data frames may form part of a two-way ranging exchange.

A reader device of a physical access control system comprises an ultra-wide band (UWB) physical layer and processing circuitry. The processing circuitry is operatively coupled to the UWB physical layer and is configured to: receive access credential information from a separate second device; receive ranging information from the second device; grant access through a physical portal according to the access credential information and ranging information; determine a number of people intending to pass through the physical portal; and generate an indication according to the determined number.

Access Point (AP) placement using Fine Time Measurement (FTM) may be provided. First, a plurality of Time-of-Flight (ToF) values between a first service end point and a second service end point may be determined. Each one of the plurality of ToF values may be derived from packets transmitted via different beamforming vector patterns at the first service end point and the second service end point. Then a minimum ToF value of the plurality of ToF values may be determined. Next, a distance between the first service end point and the second service end point may be determined based on the minimum ToF value.

An apparatus includes a vessel configured to be pressurized and heated at a well site to match desired process conditions at which a demulsifier is to break an emulsion of crude oil. The vessel includes a first end, a second end, an inlet pipe, and an outlet pipe. The inlet pipe receives crude oil and a demulsifier and mixes the crude oil and the demulsifier to form a mixture. The apparatus includes a heater surrounding at least a portion of the vessel. The heater is configured to provide heat to the mixture. The apparatus includes a guided wave radar configured to generate a reference pulse of microwave energy and detect a surface echo reflected from the mixture.

An apparatus includes a vessel configured to be pressurized and heated at a well site to match desired process conditions at which a demulsifier is to break an emulsion of crude oil. The vessel includes a first end, a second end, an inlet pipe, and an outlet pipe. The inlet pipe receives crude oil and a demulsifier and mixes the crude oil and the demulsifier to form a mixture. The apparatus includes a heater surrounding at least a portion of the vessel. The heater is configured to provide heat to the mixture. The apparatus includes a guided wave radar configured to generate a reference pulse of microwave energy and detect a surface echo reflected from the mixture.

At least some embodiments of the present invention are directed to RFID reader systems configured to estimate a directional bearing of an RFID tag. In an embodiment, the present invention is an RFID system configured in a way that upon a detection of a variance in the direction of a maximum RSSI value for a given RFID tag in response to a plurality of interrogation signals transmitted by an RFID reader over a respective plurality of different directions, the RFID reader retransmits the plurality of interrogation signals over the respective plurality of different directions with successively lower power levels until the only response(s) being received no longer exhibit the previously detected variance.

An apparatus for mobile device localization is provided with a primary device. The primary device is configured to transmit a first signal at a first transmission power level to a secondary device and to receive a response signal that is indicative of a quality indicator of the first signal as received by the secondary device. The primary device is further configured to determine a second transmission power level based on the quality indicator; transmit a second signal at the second transmission power level to the secondary device; and to determine a distance between the primary device and the secondary device based on a filtered transmission power level value.

Techniques related to measuring a time-of-flight (ToF), comprising switching a first measuring station to a main operating mode, transmitting, by the first measuring station, a first ToF packet to a remote device, switching the first measuring station to a receive mode to receive a first ToF response packet from the remote device, receiving, by the first measuring station, the first ToF response packet, determining, a time interval between transmitting of the first ToF packet and receiving the first ToF response packet, receiving a plurality of time intervals from one or more other measuring stations, determining a ToF measurement based on the first time interval and the plurality of time intervals, switching the first measuring station to a secondary operating mode, and transmitting to a second measuring station, an indication to switch to the main operating mode.

Techniques related to measuring a time-of-flight (ToF), comprising switching a first measuring station to a main operating mode, transmitting, by the first measuring station, a first ToF packet to a remote device, switching the first measuring station to a receive mode to receive a first ToF response packet from the remote device, receiving, by the first measuring station, the first ToF response packet, determining, a time interval between transmitting of the first ToF packet and receiving the first ToF response packet, receiving a plurality of time intervals from one or more other measuring stations, determining a ToF measurement based on the first time interval and the plurality of time intervals, switching the first measuring station to a secondary operating mode, and transmitting to a second measuring station, an indication to switch to the main operating mode.