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OFDM System
Goldsmith — Orthogonal Frequency Division Multiplexing
OFDM Parameters
N subcarriers
16
CP length (samples)
4
Modulation
QPSK
16-QAM
Channel
Max delay (samples)
3
SNR (dB)
25
Animation
▶ Build Subcarriers
◀ −4
+4 ▶
Metrics
CP ≥ delay?
-
SER (w/ CP)
-
SER (no CP)
-
OFDM Key Idea
Split wideband channel into N narrowband flat-fading subchannels via IFFT/FFT.
Cyclic Prefix:
Prepend last CP samples to absorb multipath delay. If
CP ≥ L
ch
, no ISI/ICI.
Equalization:
Simple 1-tap per subcarrier:
X̂[k] = Y[k] / H[k]