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EU:  DB

Status: STD 2005/06/07
Code: 32
Symbol: dB
EQ label: FIELD_OR_POWER_LEVEL_DIFF
 
Quantities associated with this Unit

Quantity: field quantity ratio (level difference)
Concept definition: The difference between two levels of field quantities with the same reference F0. The level of a field quantity is LF = ln (F/F0), where F and F0 represent two field quantities of the same kind, F0 being a reference quantity.
1 Np is the level of a field quantity when ln (F/F0) = 1, i.e. F/F0 = e.
1 dB = 10-1 B (exactly) = 1,151 293 x 10-1Np (approximately).
 
Reference type: PR
Reference: [ISO 80000-3:2006, item 3-21.b (Conversion factors and remarks)]
Supplemental references:  

Quantity: level difference of two power quantities
Concept definition: The difference between two levels of power quantities with the same reference P0. The level of a power quantity is LP = (1/2) ln (P/P0), where P and P0 represent two power quantities of the same kind, P0 being a reference quantity.
1 dB = 10-1 B (exactly) = 1,151 293 x 10-1Np (approximately).
 
Reference type: PR
Reference: [ISO 80000-3:2006, item 3-22.b (Conversion factors and remarks)]
Supplemental references: [ISO 1000:1992, Annex A, 7-21]


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