Nxp B.v.

Maxim Kulesh

Mark Steigemann

Muhammed Bolatkale

Matthias Rose

Neha Goel

Dongjin Son

Sebastián André Fatjó Carvajal

Sebastián André FatjÓ Carvajal

The disclosure relates to time of flight calculations for a lidar transceiver. Example embodiments include a method of calculating time of flight of a lidar signal, the method comprising: i) transmitting a light pulse to start () an acquisition time period having a plurality of successive time portions; ii) for each successive time portion, if a photon is received (): iia) recording () a time at which the photon is received; iib) updating () a histogram to record a cumulative count of photons received during the time portion; iic) calculating () a time difference between the time at which the photon is received relative to a reference point of the time portion; iid) updating () a cumulative total of the calculated time difference for the time portion; iii) repeating steps i) to iid) for a succession of N transmitted light pulses; iv) identifying () a peak in a time portion of the histogram; and v) estimating () a time of flight from the cumulative total of the calculated time difference for the time portion of the histogram containing the identified peak.

Time of flight calculation with inter-bin delta estimation

A first error is determined between a bandgap reference output voltage of a bandgap reference circuit at a first temperature and a target voltage. A second temperature of the bandgap reference circuit is measured. A bandgap reference output voltage of the bandgap reference circuit is predicted at the second temperature and based on the first error. A second error is determined between the bandgap reference output voltage and the target voltage. A trim parameter of the bandgap reference circuit is determined based on the second error. The bandgap reference circuit is set with the trim parameter, where a third error between a bandgap reference output voltage of the bandgap reference with the trim parameter is less than the second error.

Predicting a bandgap reference output voltage based on a model to trim a bandgap reference circuit

Various example embodiments are directed to apparatuses and methods including an apparatus having sensor circuitry and processing circuitry. In one example, sensor circuitry produces and senses detected signals corresponding to physical objects located in an operational region relative to a location of the sensor circuitry. The processing circuitry records and organizes information associated with the detected signals in a plurality of sub-histograms respectively associated with different accuracy metrics for corresponding sub-regions of the operational region, each of the plurality of sub-histograms including a set of histogram bins characterized by a bin width linked to its accuracy metric, and refines at least one of the accuracy metric by adapting one or more of the bin widths dynamically in response to the detected signals.

Histogram-based signal detection with sub-regions corresponding to adaptive bin widths

Example aspects are directed to operating a SPAD receiver such as may be used in a light detection and ranging (Lidar) system. In one example, the SPAD receiver has SPAD circuitry for multiple photon detections using a single-channel TDC (time-to-digital converter), and such photon detection is quenched after detection so as to establish an effective pre-defined OFF period. In response, the SPAD circuitry is recharged for a subsequent ON period during which the SPAD circuitry is unquenched (or armed) for further photon detection and processing.

Photon-based detection using single-channel time-to-digital conversion

Embodiments of a system and method are disclosed. In an embodiment, a LiDAR (Light Detection and Ranging) system that can include a sensor circuit comprising a controller unit, a transmitter, a gating circuit, and a receiver element, wherein the gating circuit is connected to the controller unit and to the receiver element, wherein signals detected by the sensor circuit correspond to at least one physical object located in an operating region with respect to a location of the sensor circuit and based on multiple measurements. The gating circuit can range-gate the receiver element based on a range-gating waveform, and the controller unit can provide a phase-delay parameter for phase shifting the range-gating waveform with different phase values relative to a light signal transmitted by the transmitter for different measurements by the sensor circuit.

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Hamburg, Germany

Maxim Kulesh