Interconnect channel characteristics favoring double-edge pulsewidth modulation

M-ary pulsewidth modulation (M-PWM) and double-edge pulsewidth modulation (DPWM) are compared to non-return-to-zero (NRZ) modulation in bandwidth-limited channels. DPWM features spectral characteristics that concentrate energy at lower frequencies compared to NRZ for a given data rate. Here, channel characteristics are studied that favor DPWM transmission. Each modulation format is compared at 10 Gb/s over two different electrical channels to study the signal integrity with respect to a fixed data rate and fixed minimum pulsewidth.