Fig. 2
From: Experimental evaluation of interference alignment for broadband WLAN systems
Top: frequency-domain (post-FFT) IA decoding. Bottom: time-domain (pre-FFT) IA decoding. Schematic of an OFDM transmitter that applies IA precoding in the frequency domain on a per-subcarrier basis. IA decoding is carried out in the frequency domain (top) and denoted as post-FFT IA decoding; or in the time domain (bottom), denoted as pre-FFT IA decoding