WAVEFORM DIVERSITY: PAST, PRESENT, AND FUTURE
Waveform diversity indicates the ability to adapt and diversify
dynamically the waveform to the operating environment in order to
achieve a performance gain over non-adaptive systems. This technique
can allow one or more sensors to automatically change operating
parameters such as frequency, pulse repetition time, transmit pattern,
modulation, etc. The present lecture starts with an overview concerning
the role of the waveform diversity in history, mathematics, and music
from the epoch of Pythagoras, continuing with the studies of Galileo,
Fourier, and Maxwell. Examples of waveform diversity in nature, such as
the bath sonar signal, the sounds of whales, and the cosmic microwave
background radiation are presented. A tutorial introduction to the
concept of ambiguity function, its relevant properties, and its role as
an instrument to quantify the quality of a waveform, follows.
Precisely, after a short review of the most common radar signals and
their ambiguity functions, the effects of a possible signal coding is
thoroughly described. Amplitude, phase, and frequency codes are
considered, even if a special attention is deserved to the class of
frequency coded waveforms through a Costas sequence.
Director, Dr. Alfonso Farina
SELEX Sistemi Integrati
Integrated Systems Analysis Department
Rome, Italy