Bluetooth-based Spatial-Temporal Localization

A Bluetooth-enabled device comprising a transceiver, the transceiver comprising a plurality of antennas associated with a radiofrequency (RF) chain, the Bluetooth-enabled device further comprising:

• at least one processor;
• and
• a memory having instructions stored thereon that, when executed by the at least one processor, cause the Bluetooth-enabled device to:
• control the RF chain during a first period to receive, at a single antenna selected from the plurality of antennas, a constant tone extension (CTE) signal of multiple frames transmitted by a Bluetooth-enabled transmitter over multiple frequencies prescribed in a Bluetooth communication protocol;
• control the RF chain during a second period, to switch among the plurality of antennas, according to a switching schedule associated with reception of the CTE signal at each of the plurality of antennas over multiple frames;
• determine, from first samples of the CTE signal received during the first period, an initial time-of-flight (ToF) data of the CTE signal, wherein the ToF data is indicative of a distance between the Bluetooth-enabled device and the Bluetooth-enabled transmitter, such that the distance is indicated using phase of the received CTE signal dependent on the ToF and the transmitted frequencies;
• and
• localize the Bluetooth-enabled transmitter with respect to a location of the Bluetooth-enabled device by fitting second samples of the CTE signal received during the second period into a signal model connecting the second samples with an unknown angle-of-arrival of the CTE signal received at times prescribed by the switching schedule and transmitted with an unknown ToF conditioned on the initial ToF data.