When an IoT device interfaces with the real-world we often need to measure various parameters, like the temperature, humidity or sunshine. The measurement itself happens over a chain of devices:
- Sensor – Coverts a physical phenomenon to an electric signal
- Signal conditioning – The electric signals coming from sensors might need some conditioning (processing) so they can be measured well
- Data Acquisition – The device that converts the analog signals to digital signals
Why is it so important to properly plan and design your measurements?
Measuring a physical phenomenon with a measurement chain means to conserve as much information as possible from the real-world to the digital domain. The amount of information is on the maximum in the real world signal and with converting a physical phenomenon to an electric signal, digitizing it, processing it you loose some part of the original information amount step-by-step. There is no way to get the lost information back and this is what most people miss as a idea. With signal conditioning, signal processing you prepare the signal so with the actual data acquisition you can extract the features from the original signal that are interesting for you but you cannot restore the lost pieces of information. This can be compared with applying bass enhancement on a 64kbps mp3 file. You may find it better sounding than without the extra bass, but you cannot make it sound like a 256 kbps mp3 file.