The importance of spectral efficiency in mobile communications often requires the use of
non-constant-envelop linear digital modulation schemes. These modulation techniques
carry signal information in both magnitude and phase, thus they must be linearly amplified
to avoid nonlinear signal distortion which is not correctable in a typical receiver.
A second difficulty in utilizing these modulation formats is that nonlinear amplification
generates out-of-band power (spectral regrowth). Therefore, to achieve both high energy
efficiency and spectral efficiency, some forms of linearization must be used to compensate
for the nonlinearity of power amplifiers. One powerful technique that is amenable to
monolithic integration is digital signal predistortion. Most predistorters try to achieve
the inverse nonlinear characteristic of High Power Amplifier(HPA). In this thesis a new
multi-stage digital adaptive signal predistorter is presented. The scheme is developed
from the direct iterative method with low memory requirement proposed by Cavers [1]
in combination with the multi-stage predistortion proposed by Stonick [2]. To make
the predistorter more compact a very simple and fast method called the complementary
method is proposed. The complementary method has prominent advantages over other
digital predistorters in terms of stability of the algorithm, complexity of the algorithm
and computational load. / Graduation date: 2001
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/32696 |
| Date | 14 September 2000 |
| Creators | Zhuo, Min |
| Contributors | Stonick, John T. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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