Crosstalk Rejection in 3-D-Stacked Interchip Communication With Blind Source Separation

A blind source separation (BSS) is proposed to reject the crosstalk between inductive-coupling channels in 3-D systems. The phase and permutation ambiguities inherent to BSS are compensated for in the proposed technique. A continuous-time natural gradient BSS with integrator output swing bounding, which is amenable for high-speed implementation, is also proposed. Techniques to reduce the implementation complexity for a large channel array are presented. The proposed technique shows substantial improvement results for crosstalk rejection in a high-crosstalk-coupling environment. In addition, for a 3 × 3 array channel with 1 Gb/s/channel, with a crosstalk-to-signal ratio of -3 dB, a bit-error rate of 10^-11 is obtained compared to 10^-4 without BSS.