Understanding RF Power and dB

For an RF signal to be transmitted, propagated through free space, received, and understood with any certainty, it must be sent with enough strength or energy to make the journey. This strength can be measured as the amplitude, or the height from the top peak to the bottom peak of the signal’s waveform, as shown in Figure 1-12.

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Figure 1-12 Signal Amplitude.

The strength of an RF signal is usually measured by its power, in watts (W). For example, a typical AM radio station broadcasts at a power of 50,000 W; an FM radio station might use 16,000 W. In comparison, a wireless LAN transmitter usually has a signal strength ...

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