Multi Element Array

Crosstalk Interference

Proximity between sensing elements often leads to unwanted signal leakage between adjacent channels. In a multi element array, electrical or mechanical coupling can cause the response of one node to influence the output of another. Designers use shielding and isolation trenches to minimize this effect and maintain signal purity.

Software algorithms often include compensation routines to subtract the estimated crosstalk from the raw data.

Redundancy Benefit

Operating with dozens or hundreds of nodes provides a high degree of fault tolerance for the overall system. If one part of a multi element array fails, the remaining sensors can still provide a useful, though perhaps less detailed, representation of the environment. This characteristic is vital in deep-sea or space-based applications where repair is impossible.

Averaging the signals from multiple nodes also improves the signal-to-noise ratio by a factor proportional to the square root of the total number of elements.

Integration Density

Fabricating many sensors on a single silicon or ceramic substrate requires advanced lithography and packaging techniques. The interconnect density of a multi element array presents a substantial challenge for routing signals to the processing electronics. Using multiplexers at the site of the array helps to reduce the number of wires required for the interface.

High-speed digital buses are then used to transport the combined data stream to the host computer for analysis.