Posted by Bandwidth Efficiency Calculator
Bandwidth Efficiency Calculator helps you calculate spectral efficiency, compare data rates and bandwidth, and understand how efficiently a communication system uses bandwidth.
📈 Bandwidth Efficiency Calculator
Spectral Efficiency Analysis with Visual Gauge — η = R_b / B (bits/s/Hz)
η = Rb / B = log₂(M) / (1 + α) | Practical η = Rb × Rc / B
⚙️ Input Parameters
Direct
Modulation
bps
kbps
Mbps
Gbps
Hz
kHz
MHz
GHz
1
½
⅓
¾
How to read η:
η = 1 → 100% efficiency (ideal Nyquist)
η < 1 → Inefficient (excess bandwidth)
η > 1 → Multi-level signaling used
Theoretical max η = log₂(M) bits/s/Hz
η = 1 → 100% efficiency (ideal Nyquist)
η < 1 → Inefficient (excess bandwidth)
η > 1 → Multi-level signaling used
Theoretical max η = log₂(M) bits/s/Hz
Spectral Efficiency
1.60
bits/s/Hz
10 Mbps
Input Bit Rate
5 MHz
Bandwidth
50%
Overhead
14.0 dB
Min SNR (BER=10⁻⁵)
📊 η vs. Roll-off Factor
📈 η vs. M-Order (Various α)
📋 Efficiency Comparison at Current Settings
| Scheme | η (bits/s/Hz) | Min SNR (dB) | Status |
|---|
📐 Key Formulas
Spectral Efficiency
Ratio of bit rate to bandwidth. Higher is better but requires more SNR.
η = R_b / B (bits/s/Hz)
Nyquist Limit
Maximum symbols per Hz for zero ISI. 2 symbols/s/Hz for baseband.
Symbol Rate ≤ 2B (Baud)
Roll-off Impact
Excess bandwidth factor. Higher α = more bandwidth, less ISI, easier filtering.
B = R_sym × (1 + α)
Shannon Limit
Theoretical maximum channel capacity. No system can exceed this.
C = B × log₂(1 + SNR)