Abstract:
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This paper presents a multiple LUT digital adaptive
predistorter based on a Hammerstein model that uses the return
channel to feed back information from the receiver, concretely
the bit error rate (BER), in order to train and later adapt the
specific LUT gains that permit always operating at the best
back-off level. This new predistorter architecture is aimed at
coping with modern communication standards that use adaptive
modulation (such as IEEE 802.11 or IEEE 802.16) and
therefore continuously searching the best linear amplification
to maximize power efficiency at the time that a certain quality
of service (BER) in reception is guaranteed. Simulations provided
will show the advantages of this multi-LUT configuration,
where in front of different channel conditions, linear and
efficient amplification (minimum back-off) is achieved at the
time that a certain level of BER at reception is ensured.
Index terms – Lookup tables (LUT), digital adaptive predistortion,
Hammerstein models, adaptive modulation systems,
peak to average power ratio (PAPR), bit error rate (BER). |