All systems, including filters, are causal. That means they can't produce a response to an (unpredictable) stimulus before that stimulus arrives. So, how can you build a filter that 'predicts' something?
The answer is this: it all depends on how high you set your sights for the quality and the relevance of that prediction.
So, as riffing on the “Five Things You Should Know” format that was very popular last time, let's ask five central questions whose answers can help us navigate through this filter quagmire:
•How do filters delay signals?
•How do we quantify this form of delay?
•Can we eliminate (or more than eliminate) such delay?
•How do such filters behave?
•Where are such filters useful?
The article, which is the latest in the Filter Wizard series, examines and explores the answers to these questions. To read the entire article, which was first published at EETimes Europe, click here.
About the author
Kendall Castor-Perry is a Principal Architect at Cypress Semiconductor, doing mixed-signal system analysis and design for the new PSoC platform. Kendall uses decades of experience in analog engineering, filtering and signal processing to capture signals across many domains, extract the information from them and do something useful with it.
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