Crosstalk in Inductive Coupling Communications for Multi-Stacked Chips

TL;DR

This paper analyzes crosstalk interference in inductive coupling links for multi-stacked chips, proposing techniques like coil layout optimization and time-interleaving to reduce errors, with simulation results demonstrating effectiveness.

Contribution

It introduces a 1-of-4 coding scheme and evaluates coil layout and multiplexing methods to mitigate crosstalk in inductive coupling communications.

Findings

Increased coil separation reduces interference-to-signal ratio.

Layout array changes significantly impact crosstalk reduction.

Time interleaving and 1-of-4 coding lower crosstalk but reduce bandwidth.

Abstract

This paper simulates and analyses the crosstalk interference in off-chip and on-chip communications in multi-stacked chips where Inductive Coupling Links (ICLs) are the communication medium. Crosstalk impacts data signals, leading to errors in the receiver when adjacent transmitters communicate simultaneously. We explored techniques to reduce crosstalk, including varying the coil geometry, changing the coil arrays, and using time-interleaving multiplexing. We propose a 1-of-4 technique, where two bits of data are coded into four bits, always including a '1'. Using an electromagnetic simulator, we described crosstalk behaviour and applied the results to Matlab Simulink to obtain bit-error rates (BER). Simulation results showed that the interference-to-signal ratio (ISR) decreased gradually with increased horizontal coil separation. Additionally, we observed that changing the layout arrays for the coils plays a vital role in reducing crosstalk. The 4-phase time interleaving multiplexing and 1-of-4 technique significantly reduced crosstalk at the expense of bandwidth.