Difference between dB/dBm/dBV
What is dB ?
When a physical quantity , such as power or intensity is measured relative to reference level , it can be expressed in decibels(dB). Decibels is a dimensionless unit. For example, the Signal-To-Noise Ratio can be represent in dB.
What is dBm ?
dBm stands for an absolute power level, which we can define as 10*log(P/1mW) , where the value of P is power in watts. So P=1mW equals 0 dBm.
What is the relation between dBm and dBV ?
dBm = dBV - 10log(R) + 30 in a system with resistance R. Assume R = 50 ohm, then the relation between dBm and dBV can be describe as dBV = dBm -13.
What is dB digital code word ?
Assume we have N bits digital code word, then dB digital code word can be define as the following equation :
When a physical quantity , such as power or intensity is measured relative to reference level , it can be expressed in decibels(dB). Decibels is a dimensionless unit. For example, the Signal-To-Noise Ratio can be represent in dB.
What is dBm ?
dBm stands for an absolute power level, which we can define as 10*log(P/1mW) , where the value of P is power in watts. So P=1mW equals 0 dBm.
What is the relation between dBm and dBV ?
dBm = dBV - 10log(R) + 30 in a system with resistance R. Assume R = 50 ohm, then the relation between dBm and dBV can be describe as dBV = dBm -13.
What is dB digital code word ?
Assume we have N bits digital code word, then dB digital code word can be define as the following equation :
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