The idea is simple: instead of a DSP (digital signal processor) inside the module – replacing it with transimpedance amplifier (TIA) and a driver chip with high linearity and EQ capability – LPO shifts signal processing into the host device. Linear Pluggable Optics (LPO) are a new optical transceiver technology. LPO mainly uses a Linear Driver and a Linear TIA to amplify signals linearly, rather than using a complex DSP to fully recover them digitally. It tries to preserve the original signal. CPO fundamentally changes the architecture by moving the optical engine off the pluggable module and onto the same substrate or package as the host switch Application-Specific Integrated Circuit (ASIC). The optics and electronics are "co-packaged. However, at 400G and beyond, these DSP chips can consume up to 50% of the module's total power (approximately. Half retimed optics or LRO applies re-timing mechanisms to only one direction of data flow, mostly to the transmit (Tx) signals. The receive (Rx) signals are typically handled by the host system in an LRO implementation.
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