Does not use multilevel transmission modes

Feb 18, 2010 08:17 GMT  ·  By
NEC demonstrates the LSI technology, three times faster than USB 3.0 and PCI Express
   NEC demonstrates the LSI technology, three times faster than USB 3.0 and PCI Express

With the appearance of high-definition (HD) TV and 3D video content, there has been a growth in the volume of data being processed for personal use. As such, greater demand has arisen for fast transmission of data between various equipments. NEC Corporation (NEC) and NEC Electronics Corporation (NECEL) have revealed the existence of a next-generation technology that will enable data-transfer rates of up to 16Gb/s, about three times faster than those achievable by the USB 3.0 and PCI Express interfaces.

A variety of sophisticated transmission schemes have been proposed as solutions for the growing need in data-transfer rates. These were meant to compensate for the large waveform distortion of input signals fed to the receiver while also enabling communications of over 10Gb/s.

However, such transmissions are limited in their use because they are incompatible with the binary transmission schemes widely employed by today's PCI Express and USB. The LSI technology, however, does employ binary transmission schemes while reaching 16Gb/s without using multilevel transmission modes (transmission methods that split data into multiple variables beyond 0 or 1).

In order to correct the distortion of a receiver's input signal waveform, conventional equalizers feed back received data to the input signal waveform. The time available for this, however, becomes shorter in case of higher data rates. The new technology from NEC, on the other hand, uses “a feed-forward type waveform equalization.”

“In the newly developed technology, a feed-forward type waveform equalization is employed within the analog domain: the branched input signal is delayed by one data period and is then added to the original input signal 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 equalizers,” the press release explains.

The research was presented at the IEEE International Solid State Circuits Conference (ISSCC 2010) in San Francisco, California, USA on February 9.