Electronic devices are operating at increasingly faster speeds. As a result, high speed links are often used to carry information between the electronic devices or between electronic components within an electronic device. A common type of high speed link is a Serializer/Deserializer (SerDes) link, which converts a parallel data stream from multiple data lines into a serial data stream for transmission over a single data line, and vice versa. For example, in a SerDes link, a transmitter at one end of the link may receive eight bits of data in parallel at a slower, parallel clock rate and shift out each of the eight bits serially at a faster, serial clock rate (e.g., 8× the parallel clock rate). A receiver at another end of the link may receive each of the eight bits serially at the faster, serial clock rate and output the eight bits of data in parallel at the slower, parallel clock rate. By transmitting data over a single/differential line, a SerDes link allows the number of I/O pins and interconnects of the electronic device or its components to be reduced.
Establishing a high speed link generally requires an initialization period during which both the transmitter side and the receiver side of the link are synchronized and properly trained. Training may include, for example, performing calibrations, clock data recovery (CDR), and equalization training. However, a majority of SerDes standards use a blind initialization technique in which the link is expected to become operational within a given time after powering up without any predefined signal exchange. In the case of equalization training, this means that an equalizer in the receiver is trained blindly without information about the link's channel. A “channel” refers to the transmission medium through which data is transmitted, and may be wired, wireless, or a combination of the two.
When the equalizer is trained blindly without knowledge of the channel information, the equalizer is usually not optimized and unable to minimize the intersymbol interference (ISI) effects of the channel. In view of the foregoing, there exists a need for a system and method of link optimization that overcome these problems.
USPTO Backgrounds
USPTO Backgrounds