Magneto-Inductive Powering and Uplink of In-Body Microsensors: Feasibility and High-Density Effects

This paper studies magnetic induction for wireless powering and the data uplink of microsensors, in particular for future medical in-body applications. We consider an external massive coil array as power source (1 W) and data sink. For sensor devices at 12 cm distance from the array, e.g. beneath the human skin, we compute a minimum coil size of 150 um assuming 50 nW required chip activation power and operation at 750 MHz. A 275 um coil at the sensor allows for 1 Mbit/s uplink rate. Moreover, we study resonant sensor nodes in dense swarms, a key aspect of envisioned biomedical applications. In particular, we investigate the occurring passive relaying effect and cooperative transmit beamforming in the uplink. We show that the frequency- and location-dependent signal fluctuations in such swarms allow for significant performance gains when utilized with adaptive matching, spectrally-aware signaling and node cooperation. The work is based on a general magneto-inductive MIMO system model, which is introduced first.Comment: 6 pages, to appear at IEEE WCNC 2019. This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessibl

Reducing Training Time of Deep Learning Based Digital Backpropagation by Stacking

A method for reducing the training time of a deep learning based digital backpropagation (DL-DBP) is presented. The method is based on dividing a link into smaller sections. A smaller section is then compensated by the DL-DBP algorithm and the same trained model is then reapplied to the subsequent sections. We show in a 32 GBd 16QAM 2400 km 5-channel wavelength division multiplexing transmission link experiment that the proposed stacked DL-DBPs provides a 0.41 dB gain with respect to linear compensation scheme. This needs to be compared with a 0.56 dB gain achieved by a non-stacked DL-DBPs compensated scheme for the price of a 203% increase in total training time. Furthermore, it is shown that by only training the last section of the stacked DL-DBP, one can increase the compensation performance to 0.48 dB.ISSN:1041-1135ISSN:1941-017

Deep Learning Based Digital Back Propagation with Polarization State Rotation & Phase Noise Invariance

A new deep learning training method for digital back propagation (DBP) is introduced. It is invariant to polarization state rotation and phase noise. Applying the method one gains more than 1 dB over standard DBP

400G Probabilistic Shaped PDM-64QAM Synchronization in the Frequency Domain

ISSN:1041-1135ISSN:1941-017

Deep learning based digital backpropagation demonstrating SNR gain at low complexity in a 1200 km transmission link

A deep learning (DL) based digital backpropagation (DBP) method with a 1 dB SNR gain over a conventional 1 step per span DBP is demonstrated in a 32 GBd 16QAM transmission across 1200 km. The new DL-DPB is shown to require 6 times less computational power over the conventional DBP scheme. The achievement is possible due to a novel training method in which the DL-DBP is blind to timing error, state of polarization rotation, frequency offset and phase offset. An analysis of the underlying mechanism is given. The applied method first undoes the dispersion, compensates for nonlinear effects in a distributed fashion and reduces the out of band nonlinear modulation due to compensation of the nonlinearities by having a low pass characteristic. We also show that it is sufficient to update the elements of the DL network using a signal with high nonlinearity when dispersion or nonlinearity conditions changes. Lastly, simulation results indicate that the proposed scheme is suitable to deal with impairments from transmission over longer distances. © 2020 Optical Society of America.ISSN:1094-408

Compact Optical TX and RX Macros for Computercom Monolithically Integrated in 45nm CMOS

As the reach of optical communications continues to shrink, photonics is moving from rack-to-rack datacom links to centimeter-scale in-computer applications (computercom) where different architectures are needed. Integrated optical microring resonators (MRRs) are emerging as an attractive choice for fulfilling the more stringent area and efficiency requirements: They offer scaling by wavelength division multiplexing (WDM) and high bandwidth densities. In this paper we present compact electro-optical transmit (TX) and receive (RX) macros for computercom monolithically integrated in 45nm CMOS. They operate with MRR modulators and photodetectors and include all necessary electronics and optics to enable optical links between on-chip data sources and sinks. A most compact implementation for thermal stabilization was enabled by sensing the optical device’s bias currents in the driving electronics instead of using external operating point sensing optics. Using a field-effect transistor as heating element — as is possible in monolithic integration platforms — further reduces area and power necessary for thermal control. The TX macro is shown to work for data rates up to 16 Gb/s with a 5.5 dB extinction ratio (ER) and 2.4 dB insertion loss (IL). The RX macro demonstrates a sensitivity of 71 µApp at 12 Gb/s for a BER ≤ 10-10. An intra-chip link built with the macros achieves ≤ 2.35 pJ/b electrical efficiency and a BER ≤ 10-10 at 10 Gb/s. Both macros are realized within 0.0073 mm2 which amounts to 1.4 Tb/s/mm2 bandwidth density per macro.ISSN:0733-8724ISSN:1558-221

10Gb/s Intra-Chip Compact Electro-Optical Interconnect

We demonstrate a digital-to-optical-to-digital link operating at 10 Gb/s with 2.4 pJ/b below 10-9 BER enabled by zero-change CMOS macros. All necessary electronic-photonic circuits are contained within 0.015 mm2 of silicon area

>150 GHz Hybrid-Plasmonic BaTiO3-On-SOI Modulator for CMOS Foundry Integration

A ferroelectric, metal-oxide-semiconductor (MOS) based, hybrid-plasmonic modulator is shown to feature bandwidths of >150 GHz and is tested with 32 Gbit/s NRZ. The device is relying on BaTiO3-on-SOI and potentially offers CMOS compatibility