1. What is Percentage Bandwidth?

Percentage bandwidth is a measure of how wide a frequency range is relative to its center frequency. It's commonly used in RF engineering, antenna design, and signal processing to characterize the width of a frequency band.

2. How Does the Calculator Work?

The calculator uses the percentage bandwidth formula:

Where:

• \( f_{\text{high}} \) — Upper frequency limit (Hz)
• \( f_{\text{low}} \) — Lower frequency limit (Hz)
• \( f_{\text{center}} \) — Center frequency (Hz)

Explanation: The formula calculates what percentage the difference between high and low frequencies is of the center frequency.

3. Importance of Bandwidth Calculation

Details: Percentage bandwidth is crucial in RF systems to determine how wide a frequency range a component can handle relative to its operating frequency. It helps classify antennas, filters, and amplifiers as narrowband or wideband.

4. Using the Calculator

Tips: Enter all frequencies in Hertz (Hz). The high frequency must be greater than the low frequency, and the center frequency should typically be between them. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's considered narrowband vs wideband?
A: Generally, less than 1% is narrowband, 1-25% is moderate bandwidth, and over 25% is considered wideband.

Q2: How is center frequency determined?
A: For simple cases, it's the arithmetic mean: \( (f_{\text{high}} + f_{\text{low}})/2 \). For logarithmic scales, use geometric mean.

Q3: Can percentage bandwidth exceed 100%?
A: Yes, when the frequency range is wider than the center frequency (common in ultra-wideband systems).

Q4: Why use percentage instead of absolute bandwidth?
A: Percentage bandwidth allows comparison across different frequency ranges - a 1MHz bandwidth means different things at 10MHz vs 10GHz.

Q5: How does this relate to Q factor?
A: For narrowband systems, Q ≈ 1/(% bandwidth in decimal form). A 2% bandwidth corresponds to Q ≈ 50.