# Can we convert dBm to dB?

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## Can we convert dBm to dB?

dB is a relative unit that describes gain and dBm is an absolute unit referenced to 1 milliwatt (mW). So you can’t convert dB to dBm.

## What is relation between dB and dBm?

dB quantifies the ratio between two values, whereas dBm expresses the absolute power level. dBm is an absolute unit, whereas dB is a dimensionless unit. dBm is always relative to 1mW, while dB is expressed in watts and can be relative to other powers.

## Can you subtract dB from dBm?

Any time you subtract two dB values with a reference level specified (dBm, dBW, dBFS, etc.) you get a ratio expressed as decibels, which is independent of the reference level and therefore should not be written with one.

## How do you convert dB to dBm?

Decibels are used to represent the ratio of two quantities of power: db = 10 log P1/P0 . In the case of dbm the reference power P0 is 1 milliwatt : dbm = 10 log P1/1mw. Inverting this equation gives the power in terms of the reference power: P1= P010db/10. In the case of dbm the equation is P1= 1mw·10dbm/10.

## How do I convert dBW to dB?

To convert a ratio to dB, do log and then times by 10. Example: dB = +12.5 dB….dBW and Watts W.

dBW scale Watts
-10 dBW 0.1 W
-30 dBW 0.001 W
-30 dBW 0 dBm

## Can we add two dBm values?

Well, you can’t. You can’t add dBm to dBm. If, for example, you have a circuit or a device that combines the power of one signal of 10 dBm (10 mW) with the power of another signal of 13 dBm (20 mW), the result is 10 mW + 20 mW = 30 mW which is 14.8 dBm.

20W=115.4dB.

## Which is greater a dBW or a DBM?

The power in dBW ( P(dBW)) is equal to 10 raised by the power in dBm ( P(dBm)) divided by 10: For example: what is the power in watts for power consumption of 40dBm? dB is a relative unit that describes gain and dBm is an absolute unit referenced to 1 milliwatt (mW). So you can’t convert dB to dBm.

## Which is the correct formula for calculating dBm?

The formula for calculating dBm measurement is 10 x log (signal strength per milliwatts). Measurement of signal strength is in dBm and is the most accurate measurement available. To recap, we use dB when expressing a ratio between two values and dBm when determining the exact power.

## How is the strength of a DBM signal determined?

If you test the signal and is comes up as -95 dBm, that’s a pretty weak signal. dBm is determined by factors of 3 and 10. Signal strength doubles every 3 dBm. For example, a -30 dBm signal is twice as powerful as a -33 dBm signal, and a -84 dBm signal is 4 times as powerful as a -90 dBm signal. Going back to the -95 dBm original signal you have.

## What’s the difference between 3 dB and 10 dB?

3 dB of loss = -3 dB = halves signal strength 3 dB of gain = +3 dB = doubles signal strength 10 dB of loss = -10 dB = 10 times less signal strength (0.1 mW = -10 dBm, 0.01 mW = -20 dBm, etc.) 10 dB of gain = +10 dB = 10 times more signal strength (0.00001 mW = -50 dBm, 0.0001 mW = -40 dBm, etc.)