On the Maximum Efficiency of Power Amplifiers in OFDM Broadcast Systems with Envelope Following
نویسندگان
چکیده
We suggest a method for determining the efficiency of the power amplifier of an OFDM broadcast system. We present how far the efficiency of conventional power amplifiers can be increased by applying envelope following. The dependency of the efficiency on the probability of clipping is derived. In this context all three possibilities of operating point adjustment are investigated. Finally, we show that by adjusting only the operating point voltage of the power amplifier the efficiency of OFDM broadcast systems can be doubled.
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