In this work, we have proposed and experimentally demonstrated a true full-duplex IO (TFD-IO) for high-speed high-density interfaces. The proposed TFD-IO can be used as an independent module that converts a unidirectional IO/interconnect to a fully bidirectional IO/interconnect, to ideally double the throughput of the high-speed interface. The TFD-IO uses a correlation-based technique to cancel the self-interference (SI) and echoes adaptively in the background. The signals transmitted from the near-end and the far-end can use independent baud nm CMOS technology, and demonstrated with bidirectional throughputs of up to 12.8 Gb/s.

In this work, we have proposed and experimentally demonstrated a true full-duplex IO (TFD-IO) for high-speed high-density interfaces. The proposed TFD-IO can be used as an independent module that converts a unidirectional IO/interconnect to a fully bidirectional IO/interconnect, to ideally double the throughput of the high-speed interface. The TFD-IO uses a correlation-based technique to cancel the self-interference (SI) adaptively in the background. The signals transmitted from the near-end and the far-end can use independent baud-rates and signaling schemes in a TFD-IO. A proof-of-concept design of the TFD-IO module has been fabricated in a 65 nm CMOS technology, and demonstrated with bidirectional throughputs of up to 12.8\,Gb/s.

In this work, we introduce the concept of true full-duplexing (TFD) for high-speed interconnects. Full-duplex transceivers at the two ends of an interconnect can support simultaneous bidirectional data transfer. Full-duplexing can help in increasing the throughput per lane and also enable higher data transfer bandwidths without an increase in the routing density. The proposed TFD approach allows for the use of independent modulation schemes as well as independent baud-rates by the transceivers on either side of the interconnect. The approach also obviates the requirement of a dedicated start-up protocol or a training sequence for cancellation of near-end interference in the TFD transceivers. In this work, we have used a correlation-based cancellation technique which can support background cancellation of the interference. Here, we demonstrate a 100 Gbps TFD link over a 1 m long coaxial cable with off-the-shelf components, which is the first demonstration of a full-duplex communication link at such a high data rate.

In this paper, we propose a true full-duplex cell for space-constrained high-speed interconnects. The proposed interconnect can replace conventional simplex interconnects due to its ability to double the data rate with ease in PCB floor planning. The proposed ratioed driver-based self-interference (SI) cancellation technique uses an automatically adjustable on-chip background calibration which minimizes SI, to retrieve the far-end signal faithfully. The techniques used in the design relax linearity requirements and reduce power consumption for the transceiver. The SI cancellation is independent of the modulation format of the incoming signal from the far-end transmitter. Using the proposed technique reliable communication is possible between near-end and far-end transceivers without any synchronization. The proof-of-concept circuit has been designed and verified in a low-leakage 65 nm CMOS technology. The full-duplex nature of the transceiver can significantly reduce cross-talk in high-density interconnects compared to its simplex counterparts for the same throughput due to less stringent spacing requirements.