Word for sensors that collect the same data in two different ways
Domain is often used in precisely the situation you describe. So you could call it a
dual-domain system
or you could also use "multi-domain system."
I also personally like milieu basically meaning the same, but even broader. I would say that a different milieu can be whole different paradigm—for instance, audio versus visual. A different domain tends to mean a hugely different metric within the same paradigm.
Redundant is also very close to what you are asking. Quite simply, redundant means a second independent system, which is after all exactly what you describe. I'm guessing a combination of redundant with something else is your best bet. "Two-channel" would also make a lot of sense to mathematicians.
Another approach here is hyphenating it, as in: "We defeated the stealth mechanism with the dual-mode vibration-radio detection device!" or for an ad brochure: "Redundant independent dual-mode multi-spectrum multi-system intruder detection!
My final candidates would be something like:
- dual independent-domain detection (DIDD) system
- dual-milieu detection (DMD) system
- redundant sensors or doubly-redundant sensors
- dual-mode sensors
- dual-spectrum sensing or dual-spectrum detection
- multi-detection sensors
As a final suggestion, you're probably making it hard for yourself by saying "sensors." If it's specifically a camera, heart-rate monitor, radar, or whatever, you'd do better to go with that specific term, since what you're trying to say is hard enough anyway.
It's a late suggestion, but you could use bimodal. Modality is used frequently in my former field of interface design to describe the mode of input or output (e.g., visual, vibrotactile, haptic). An interface that uses multiple modalities is referred to as "multimodal" and I think we applied similar terms to the sensor (non-human) inputs as well.
If the sensors are correlated, the implication is that they will sens some things the same, some differently.
This is the closest one-word answer I can think of, but I don't think it is the best way to describe the relationship between the two kinds of sensors. Correlation might be used, but I think it needs to be embellished:
The sensors, though covering different wavelengths, will both result in detection of the object.
could be transformed to:
The detection success is correlated between the two sensors.