Power Output and Signal Strength explained

One usual question we get at our technical support center is what is dB? and as conventional wisdom prevails the more dB means more power and hence larger the area being covered. This school of thought is only true to a certain extent, because a signal gets amplified for strength more then just a booster signal is the result. The resulting signal has to be limited and cleaned from any noise that got fed into the amplifier at the input to the antenna. The resulting signal is better version of the signal that has been fed into the system for all purpose.

Decibel Meter

Decibel Meter


Now, without limiting the amplification factor of the original signal and just boosting the signal strength alone to a fancy attractive large number will only corrupt the signal. The signal can be understood better if one thinks of it as a RPM meter on your car. The revolution per minute indicates how hard the engine is pushed under peak performance. This is indicative of how efficiently the power is getting transferred from the engine to the wheels through the axle. Now, their is a red line on your RPM indicator that indicates how the optimum value of the engine performance and beyond a certain value the indicator gets represented in red. The red region on the RPM meter is indicative of where the engine is being pushed out of its intended operation conditions. Similarly when the amplifier is amplifying the signal beyond the optimum operation value, then all that gets amplified is the unwanted noise and that noise reduces the range over which the signal gets broadcast. The point that this article is intended to make is that, just because an amplifier system has higher gain does not mean that it has higher performance. The gain achieved must match the input value as well.