Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Good Code Sets from Complementary Pairs via Discrete Frequency Chips   It is shown that replacing the sinusoidal chip in Golay complementary code
pairs by special classes of waveforms that satisfy two conditions,
symmetry/anti-symmetry and quazi-orthogonality in the convolution sense,
renders the complementary codes immune to frequency selective fading and also
allows for concatenating them in time using one frequency band/channel. This
results in a zero-sidelobe region around the mainlobe and an adjacent region of
small cross-correlation sidelobes. The symmetry/anti-symmetry property results
in the zero-sidelobe region on either side of the mainlobe, while
quasi-orthogonality of the two chips keeps the adjacent region of
cross-correlations small. Such codes are constructed using discrete
frequency-coding waveforms (DFCW) based on linear frequency modulation (LFM)
and piecewise LFM (PLFM) waveforms as chips for the complementary code pair, as
they satisfy both the symmetry/anti-symmetry and quasi-orthogonality
conditions. It is also shown that changing the slopes/chirp rates of the DFCW
waveforms (based on LFM and PLFM waveforms) used as chips with the same
complementary code pair results in good code sets with a zero-sidelobe region.
It is also shown that a second good code set with a zero-sidelobe region could
be constructed from the mates of the complementary code pair, while using the
same DFCW waveforms as their chips. The cross-correlation between the two sets
is shown to contain a zero-sidelobe region and an adjacent region of small
cross-correlation sidelobes. Thus, the two sets are quasi-orthogonal and could
be combined to form a good code set with twice the number of codes without
affecting their cross-correlation properties. Or a better good code set with
the same number codes could be constructed by choosing the best candidates form
the two sets. Such code sets find utility in multiple input-multiple output
(MIMO) radar applications.

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The categories of this paper are: gr-qc
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: econ
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The categories of this paper are: q-alg
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio
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The categories of this paper are: mtrl-th
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The categories of this paper are: nucl-ex
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The categories of this paper are: plasm-ph
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The categories of this paper are: nlin
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The categories of this paper are: quant-ph
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The categories of this paper are: math-ph