Which of the following techniques are suitable for online, real-time filtering?

Synchronized averaging
Derivative-based filter
Adaptive filter
Moving average filter

Adaptive filter

Moving average filte

To determine which of the given techniques are suitable for online, real-time filtering, let's understand each technique and its characteristics.

1. Synchronized Averaging:
Synchronized averaging is a technique that involves averaging multiple samples of a signal. It is suitable for offline analysis because it requires collecting a set of samples before the averaging process. Therefore, synchronized averaging is not suitable for online, real-time filtering as it introduces a delay.

2. Derivative-Based Filter:
A derivative-based filter calculates the rate of change of a signal. It is commonly used to detect the edges or slopes in a signal. However, derivative-based filters can be sensitive to noise, and real-time implementation may be challenging due to their high computational complexity and susceptibility to noise.

3. Adaptive Filter:
An adaptive filter is a filter that adjusts its parameters based on the characteristics of the input signal. It can track changes in the signal dynamics and adapt to varying conditions. Adaptive filters are particularly suitable for online, real-time filtering as they can continuously adjust their parameters to provide the best filtering performance.

4. Moving Average Filter:
A moving average filter works by calculating the average of a sliding window of samples. It smooths out variations in the signal by effectively reducing high-frequency noise. Moving average filters are commonly used in real-time applications as they are easy to implement and operate in real-time. They introduce a small delay proportional to the length of the window.

Based on the explanations above, the suitable techniques for online, real-time filtering are the Adaptive Filter and the Moving Average Filter.