The USB 3.0 standard allows a maximum bandwidth of 4.8Gbps, but if it's up to NEC, this can be more than tripled to 16Gbps. The company send out a statement that it had successfully demonstrated a serial bus that it believes can hit that speed thanks to a new technology that significantly reduces interference:
At high throughput rates, signals become distorted, especially over long cable lengths. Bus interface chips use 'adaptive equalisation' to correct the distortion, and they do this by splitting the signal into two and feeding one back onto the input signal. The snag: the higher the frequency, the quicker the chip has to perform the feedback operation to successfully reduce the distortion.
NEC said it gets around this problem by adding a delay tied to the data rate to the feedback waveform.
"This procedure greatly reduces the nearest-neighbor inter-bit interference in the signal waveform and thus successfully alleviates the issue of feedback-time constraint inherent in conventional equalisers," said NEC's boffins.