Matching alignment

The ergodic interference alignment scheme allows each user in a K-user interference channel to attain half its interference-free rate at any signal-to-noise ratio (SNR). However, this comes at the cost of extraordinarily long delays, since each channel matrix must be paired with a complementary matrix that can cancel out its off-diagonal terms. In this paper, we investigate the opposite approach. Rather than waiting for perfect matches, we simply try to pair together the available channel matrices to attain the highest possible sum rate. We show that this problem is closely connected to the problem of maximum weight matching, which allows us to efficiently evaluate the numerical performance of our scheme.