Ultrasonic Sensor Device Using Frequency-Modulated Excitation Patterns

The patent applies local quality by assigning different excitation patterns (codes) to different ultrasonic sensors based on their spatial positions. Specifically, sensors are grouped into first and second groups, with adjacent sensors receiving different codes. This localized differentiation ensures that each sensor's signal can be uniquely identified and separated by matched filters, enabling simultaneous operation of multiple sensors without signal confusion.

The patent addresses the bandwidth limitation of resonant transducers by changing the temporal parameters of the excitation signals. Instead of relying solely on frequency diversity (which is constrained by narrow bandwidth), the system uses time-modulated excitation patterns (codes) with distinct temporal structures. Matched filters correlate received signals with these known temporal patterns, enabling effective separation even when frequency content overlaps, thus maintaining sensitivity while achieving multi-sensor operation.

The patent applies segmentation by dividing the sensor array into distinct groups (first group and second group) and assigning different excitation patterns to each group. This segmentation allows the control unit to operate sensors in an organized manner while maintaining signal distinguishability. The matched filters are correspondingly segmented to process signals from each group, enabling simple centralized control without sacrificing the ability to identify individual sensor echoes.