Understanding Sampling Theorem
The Sampling Theorem, formulated by Claude Shannon, is foundational in digital signal processing, defining conditions for perfect reconstruction of a signal from its samples.
Nyquist Rate Essentials
The Nyquist Rate is twice the highest frequency present in the signal. Sampling below this rate causes aliasing, blending high frequencies indistinguishably with low ones.
Aliasing: Unexpected Consequences
Aliasing distorts signals, producing artifacts. It's akin to wagon wheels appearing to spin backwards in movies, a visual sampling below the Nyquist Rate.
Practical Sampling Applications
Sampling theorem isn't just theory; it's crucial in digital audio, imaging, and communications. Your MP3s and JPEGs exist thanks to proper sampling.
Oversampling Advantages
Oversampling, sampling at a rate much higher than the Nyquist Rate, improves resolution, reduces noise, and eases filter design in digital systems.
Quantization and Sampling
Quantization follows sampling, converting amplitude into bits. Together, they digitize analog signals, but quantization introduces its own error, quantization noise.
Breaking Nyquist's Limits?
Compressed Sensing is a modern technique challenging Nyquist, allowing reconstruction with fewer samples by leveraging signal sparsity and optimization algorithms.