Sample and hold - LTI filter

1. What does an LTI filter do?
2. What does sample and hold do?
3. What is the purpose of sample and hold circuit in PCM?
4. Is filter an LTI system?

What does an LTI filter do?

LTI filters are important in audio engineering because they are the only filters that preserve signal frequencies.

What does sample and hold do?

In electronics, a sample and hold (also known as sample and follow) circuit is an analog device that samples (captures, takes) the voltage of a continuously varying analog signal and holds (locks, freezes) its value at a constant level for a specified minimum period of time.

What is the purpose of sample and hold circuit in PCM?

The sample-and-hold amplifier, or SHA, is a critical part of most data acquisition systems. It captures an analog signal and holds it during some operation (most commonly analog-digital conversion).

Is filter an LTI system?

LTI system theory describes linear time-invariant (LTI) filters of all types. LTI filters can be completely described by their frequency response and phase response, the specification of which uniquely defines their impulse response, and vice versa.