Inventors:
Boris Aleiner - Somerset NJ
Winston Hong Lieu - Holmdel NJ
Assignee:
Lucent Technologies Inc. - Murray Hill NJ
International Classification:
H04B 104
Abstract:
A apparatus linearizing and technique for linearizing a non-linear power amplifier used in a transmitter of, e. g. , a TDMA mobile wireless telephone. Linearization of the non-linear amplifier by changing the shape of the input signal is performed when the input signal level is high, thus increasing efficiency or reducing power consumption at that time, albeit at the cost of increased inter-symbol interference (ISI). However, since the input signals at that time are at a high level, the increased ISI can be tolerated and adjacent symbols can still be distinguished from one another. The invention allows use of a non-linear power amplifier which typically enjoys a lower current consumption than that of a linear power amplifier, thus increasing the time between battery recharges and/or reducing the overall size of the wireless telephone device. The power amplifier is operated in a linear mode when transmitted power is low, thus allowing differentiation between adjacent symbols (i. e. , improvement of ISI).