Here's how to convert dB units (with usually a 1 Watt or whatever 1 value as reference) to dBm units (with a 1 miliWatt reference value):
x= value to be converted
x [dB]= x + 30 [dBm]
Proof:
P= 1 Watt
--> 10*log10(1)= 0 [dB] (this is 1 Watt in dB)
--> 10*log10(1/(1*10^(-3)))= 10*log(1*10^3)= 30 dBm (this is 1 Watt to dBm)
Now, if you do whatever number of examples you want to do, you'll end up in concluding the conversion dB to dBm is totally linear without of actually having to proof the linear properties. (i'm too lazy to write it here).
Hope this helps....
Regards,
STMI
30
The answer is 22.
Multiply the radians by 180/PI to convert to degrees.
To convert from sq cm to sq mm, multiply by 100.To convert from sq cm to sq mm, multiply by 100.To convert from sq cm to sq mm, multiply by 100.To convert from sq cm to sq mm, multiply by 100.
To what?
the first convert the power in dBm to MW, the define of dBm=10 log (P MW) -10 log ( 1mw). example: let P=-2 dBm convert this to dB? answer: Pmw= inv log(-2/10)=0.630mw*1000 micw/mw=630 microw 10log(630)=28dB
dBm is defined as power ratio in decibel (dB) referenced to one milliwatt (mW). It is an abbreviation for dB with respect to 1 mW and the "m" in dBm stands for milliwatt. dBm is different from dB. dBm represents absolute power, whereas in audio engineering the decibel is usually a voltage ratio of two values and is used then to represent gain or attenuation of an audio amplifier, or an audio damping pad.
dBm is defined as power ratio in decibel (dB) referenced to one milliwatt (mW). It is an abbreviation for dB with respect to 1 mW and the "m" in dBm stands for milliwatt. dBm is different from dB. dBm represents absolute power, whereas in audio engineering the decibel is usually a voltage ratio of two values and is used then to represent gain or attenuation of an audio amplifier, or an audio damping pad.
dBm us almost exactly the same as dB. The only difference is that there is a reference of 1 Watt = 0 dB, and 1 mW = 0 dBm. dBm is defined as power ratio in decibel (dB) referenced to one milliwatt (mW). It is an abbreviation for dB with respect to 1 mW and the "m" in dBm stands for milliwatt. dBm is different from dB. dBm represents absolute power, whereas in audio engineering the decibel is usually a voltage ratio of two values and is used then to represent gain or attenuation of an audio amplifier, or an audio damping pad. PdBm = 10*log10(1000*10W) = 40dBm
The 'm' in dBm means the power is referenced to 1mW. So, the power in dBm equals 10 times the log of the power in mW, or P(dBm) = 10*log(P(mW)/1mW). For example, 1W = 1000mW, so 10*log(1000/1) = 30dBm.
Two ways to do it. In this particular problem, it's a matter of opinionwhich one is easier and which one is harder.Way #1:Convert dBm to watts, multiply by gains, convert output watts to dBm.+20 dBm = 0.1 watt.Output power = (0.1 watt) x (ap1) x (ap2) x (ap3) = 0.1 x 10 x 4 x 23 = 92 watts = +49.64 dBmWay #2:Convert each gain ratio to dB, then add all dB to input power.ap1 = 10 = 10 dBap2 = 4 = 6.02 dBap3 = 23 = 13.62 dB+20 dBm + 10dB + 6.02 dB + 13.62 dB = +49.64 dBm
dBm is defined as power ratio in decibel (dB) referenced to one milliwatt (mW). It is an abbreviation for dB with respect to 1 mW and the "m" in dBm stands for milliwatt. dBm is different from dB. dBm represents absolute power, whereas in audio engineering the decibel is usually a voltage ratio of two values and is used then to represent gain or attenuation of an audio amplifier, or an audio damping pad.
20 dbm
dBm us almost exactly the same as dB. The only difference is that there is a reference of 1 Watt = 0 dB, and 1 mW = 0 dBm. Sorry but that is incorrect. db is a ratio and not an absolute value, by it self it means nothing. you got the dbm part right, 1 mW = 0 dbm and it is an absolute value.
The decibel scale is a logarithmic scale where each change in three dB represents a power factor change of two. (3 dB is power times two, 6 dB is power times four, 9 dB is power times 8, etc. Similarly, -3dB is power divided by two, -6 dB is power divided by four, etc.) Zero dB is assigned some arbitrary reference power. One example is 1 mV across 600 ohms. If you double the voltage into a constant resistance, the power quadruples, so 2 mV would be +6 dB, 4 mV would be +12 dB, etc. The letter after dB is the reference power. In the case of dBm, it means that 0 dB is 1 milliwatt, so 2 milliwatt is +3 dB, etc. There are many dB scales, such as dBa, used in sound measurements. Still, fundamentally, 3 dB is a doubling of power, -3 dB is a halving of power, so, for any arbitrary scale, say dBq, then saying +6dBq is saying a power four times higher than 0 dBq. In the end, dBm plus dBm is delta dB, with no scale.
How do I convert a .db file?
EIRP (Dbm)= Output Power(Dbm)-Losses(from cables & adapters)+Antenna Gain(Db)