Sampling rate, also known as sample rate or sampling frequency, is used in digital signal processing and electronics. It refers to the number of samples of a continuous signal taken per second to convert it into a discrete signal.
This tool calculates the sampling rate of a system
Calculator
Enter
- the number of samples
- time period over which the samples were collected
The tool will compute the sample rate
Background
Sampling rate is expressed in hertz (Hz) and plays a significant role in determining the accuracy and quality of digital representations of analog signals.
What Is Sampling Rate?
When an analog signal, such as sound or a voltage reading, is digitized, the continuous waveform is sampled at discrete intervals. The sampling rate dictates how frequently these samples are taken. A higher sampling rate captures more details of the original signal, leading to greater accuracy. However, it also increases the data size and processing requirements.
For example:
- A CD-quality audio file is sampled at 44,100 Hz (44.1 kHz), meaning 44,100 samples per second.
- Arduino’s built-in ADC (analog-to-digital converter) has a typical default sampling rate of about 9,600 samples per second at 10-bit resolution.
Why Is Sampling Rate Important?
The choice of sampling rate affects:
- Signal Fidelity: According to the Nyquist-Shannon theorem, the sampling rate must be at least twice the maximum frequency of the signal to avoid aliasing (distortion caused by undersampling).
- Data Size: Higher sampling rates generate larger datasets, which require more storage and processing power.
- Real-Time Applications: For applications like audio processing or sensor monitoring, the sampling rate needs to be high enough to capture relevant signal changes in real time.
How to Calculate Sampling Rate
To calculate the sampling rate, use the formula:
fs = N / T
Where:
- fs = Sampling rate (Hz)
- N = Number of samples
- T = Time interval (seconds) over which the samples were collected
Example Calculation
Suppose you have a system where 1000 samples are collected over a time interval of 2 seconds
This means the system samples the signal 500 times per second.
Applications of Sampling Rate Calculators
- Audio Engineering: Ensuring high-quality sound by preventing aliasing while minimizing file sizes.
- Data Acquisition Systems: Optimizing sensor sampling rates in IoT devices.
- Medical Devices: Calculating rates for ECG machines to accurately capture heart signals.
- Embedded Systems: Configuring ADCs in microcontrollers like Arduino to balance performance and resource use.