Manual

Leddar™One Sensing Module 12

the signal is captured while the reception lens of the sensor is shielded from

the backscattered light. The sensor comes with a static noise factory

calibration. However, the default calibration can be updated by the user using

Leddar

Configurator, see Section 4.4.12 for more details.

1.3.3. Pulse Detection

The objects in the sensor field of detection create a particular signature in the

full-waveform signal called pulses. The pulse detector analyses the full-

waveform signal in order to recognize these pulses and compute their

distance. By nature, time-of-flight sensor using full-waveform analysis is able

to detect several distinct objects with a single photodiode element.

The detected pulses have specific amplitudes based on their distance from the

sensor and on the reflectivity of the objects. It is well known that pulses of

small amplitudes do not lead to accurate and precise distance measurements.

Consequently, the algorithm removes all pulses with amplitudes under a given

threshold. This threshold depends on the acquisition settings of the sensor,

see Section 5.5.2 for more details.

1.3.4. Saturation Compensation

The algorithm classifies the detected pulses based on their shape. The

LeddarOne

determines which pulses are saturated and which have a normal

shape. It is noted that other families of the products have more advanced

classification technology such as merged object discrimination. Saturated

pulse occurs when the signal backscattered by the object is so strong that the

full-waveform signal is clipped. If not treated, this phenomenon creates an

important degradation of the distance measurement accuracy. It is why a

saturation compensation algorithm is executed when saturated pulses are

detected. This innovative algorithm uses a sophisticated approach to provide

a distance measurement accuracy better than 10 cm even with a strongly

clipped signal.

1.3.5. Temperature Compensation

The signal processing algorithm also embeds an advanced temperature

compensation scheme which attenuates the distance measurement drift over

large and sudden sensor temperature changes. With this algorithm, the

distance measurements stabilize inside 1 cm in less than 10 seconds on cold

sensor startup. The temperature compensation also ensures optimal accuracy

over the full operating temperature range.