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Spectrum
shoulder
control
t
High PAPR=PMAX /<P>=N causes poor
transmitter efficiency η ≈ 3%
FFT requires N•log2N calculations
Narrowband carriers require high
frequency stability Δf ≤ 10% R/N
Large symbols ~12000 bit (N ≈ 2000,
C/B ≈ 6 bit) for some protocols
Narrowband interference kills sync
Adjustable resistance to multipath
Nearly rectangular frequency spectrum
Weak FEC sufficient
Spectral efficiency C/B reaches theory
for BPSK, QPSK, QAM
Allows single-frequency networks
(SFN)