Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Calculate slope of a noisy signal in real time (with minimal phase error)?

Status
Not open for further replies.

swen_s

Member level 1
Member level 1
Joined
Nov 29, 2012
Messages
40
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,288
Activity points
1,598
Hello

I need to calculate the slope of a temperature (Kelvin/s) from a temperature sensor.

The solution today is an Kalman filter with static kalman gain. This filter gives wery smooth derivative/slope. But it causes a phase shift of the derivative.

I don't know how to fine tune the Kalman gain.

Is there another method for calculating slope in real time?

I can't just take (T(n) - T(n-1)) / sampletime. It gets too noisy. And if I filter the temperature first it gets a phase shift.
 

So you need a noise rejection filter and you have a sampling rate which has a maximal signal bandwidth that can exceed the Shannon sampling theorem rate.
But you are only interested in real-time rate changes of temperature but know that phase shift with filtering causes time delay or group delay.

Can you model a raised cosine filter on the sensor data in KF at 1/2 the sampling rate? ( don't ask me)
 
Last edited:

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top