Dynamic RF amplifier bias control for digital wireless communications devices
AssigneeCisco Technology, Inc.
InventorDavid Petsko
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AssigneeCisco Technology, Inc.
InventorDavid Petsko
Estimating the term…
An adaptive bias control scheme for an Orthogonal Frequency Division Multiplex (“OFDM”) transmitter. The transmitter chain is comprised of class A amplifiers. The amplifiers in the transmit chain are backed off from P1dB to ensure linear amplification of the signal. Amplifier back off is defined as (Amplifier P1dB) minus (Average Signal Power). Since the efficiency of the amplifier decreases in direct proportion, to the back off, it is desirable to minimize back off while maintaining linearity. The back off is dependent on the peak to average power ratio (“PAPR”) of the OFDM waveform. The PAPR is measured on a symbol by symbol basis and the amplifier P1dB is adjusted in proportion to the PAPR of the symbol, maintaining a P1dB sufficient to provide the required back off dictated by the maximum PAPR of the OFDM waveform, but can be lowered for symbols with PAPR below the maximum. The average operating point of the amplifiers is reduced by the adaptive bias control on a symbol-by-symbol basis.
An apparatus for dynamically adjusting the bias of an amplifier, comprising:
A method for dynamically adjusting the bias of an amplifier, the steps comprising:
A computer readable medium of instructions, comprising:
An apparatus for dynamically adjusting the bias of an amplifier, comprising:
Dependencies are inferred from the claim text.