Introduction to Digital Signal Processing Concepts

Analogue Signals

Continuous signals defined at every instant in time.

Digital Signals

Discrete signals defined at specific instances in time.

Sampling Frequency

Rate at which continuous signals are sampled, in Hz.

Nyquist Theorem

Sample at twice the highest frequency to avoid aliasing.

Aliasing

Distortion when signals overlap due to insufficient sampling.

Quantization

Rounding of sample values to fit discrete values.

Digitization

Conversion of quantized samples to binary numbers.

Quantization Error

Noise due to rounding errors in digital conversion.

Dither

Random noise added to mask quantization error.

Digital Filter

Mathematical formula transforming input signal to output.

Digital Hearing Aid

Device processing sound digitally for individual users.

Processing Algorithm

Computer program manipulating digital signals in hearing aids.

Digital Filterbank

Collection of filters applied to frequency channels.

Compression

Reducing file size by removing redundant audio data.

WAV File

Uncompressed digital audio format developed by Microsoft.

AIFF File

Uncompressed digital audio format developed by Apple.

MP3 File

Compressed audio format removing masked sound samples.

Forward Masking

Long sound masking a shorter tone pip.

RMS Calculation

Average amplitude measurement of a digital signal.

Digital to Analog Conversion

Process of converting binary numbers back to voltages.

Reconstruction Filter

Low-pass filter removing unwanted frequency components.

Processing Delay

Time lag between input and output in hearing aids.

Feedback Suppression

Technique to reduce echo in hearing aids.

Noise Reduction

Process of minimizing unwanted sound in audio signals.

Dynamic Range Adjustment

Modifying the range between the quietest and loudest sounds.

Battery Power Consumption

Energy usage influenced by processing features in devices.

Quantization Steps

Discrete values representing amplitude in digital signals.

Digital Audio Applications

Includes transmission, amplification, and filtering of audio.

Hearing Aid Receiver

Miniature loudspeaker outputting processed sound in aids.