SEW Day 6 - dB Flashcards
(10 cards)
Describe decibels
Explain the benefits of decibels
Summarize decibels rules of thumb
Perform basic decibel conversions
A decibel (dB)
- a logarithmic unit used to measure signals and communication
- Makes large and small numbers more manageable
The dB is a logarithmic unit of ___ named for Alexander Graham Bell
The Bel is a logarithmic unit of intensity named for Alexander Graham Bell
decibel = ____ of a Bel
one-tenth
turns exponential changes into linear changes
Logarithmic Scaling
- Linear scales increment by a constant: ___
- Logarithmic scales increase by a factor of the base: ___
- 1, 2, 3, 4, etc.
- 1, 10, 100, 1000, etc.
- express a ratio relative to a reference value on a logarithmic scale
- are unitless ratios representing increases or decreases in values
Decibels (dB)
dB Suffix: dBW or dBm
Reference Value:
Unit
1W and watts
1mW and milliwatt
dB Rules of Tens
For every 10 dB increase, the signal strength (linear value) is multiplied by 10
For every 10 dB decrease, the signal strength (linear value) is divided by 10