Joint transmitter and receiver gain optimization for high-speed serial data systems

摘要

Embodiments of the present invention allow for adjustment of transmitter amplitude during joint transmitter (TX) and receiver (RX) equalization. During joint TX and RX adaptation, when the receiver requires a gain update, the receiver gain update is masked above or below a preset range. The RX gain update (instruction) is encoded into a transmitter amplitude update (instruction) transferred through back channel communication. The translation of RX gain to TX amplitude update is performed after the RX gain reaches a specified range. Such masking, encoding and translation reserves a certain amount RX gain range to account for RX gain variation due to process, voltage, and temperature (PVT) changes over time, and also to offer better linear equalization in the receiver over a constrained VGA bandwidth.

主权项

1. Apparatus for joint adaptation of transmitter and receiver gain during an initial adaptation period, the apparatus comprising:
a receiver having an amplifier, wherein the receiver is configured to adaptively update the amplifier gain via a receiver gain update process to generate each receiver gain update; a transmitter mapper coupled to the receiver; and a back-channel coupled between a transmitter and the transmitter mapper; wherein the transmitter mapper is adapted to:
a) monitor a receiver gain update of the receiver, andb) compare the receiver gain update with a constrained range of the amplifier; wherein, if the receiver gain update is outside of the constrained range of the amplifier, the transmitter mapper is further adapted to translate the receiver gain update into a transmitter amplitude gain and generate a transmitter update request including the transmitter amplitude gain for transmission through the back-channel.