{"title":"A 216 nW/channel DSP engine for triggering theta phase-locked brain stimulation","authors":"Ahmed Alzuhair, D. Markovic","doi":"10.1109/BIOCAS.2017.8325189","DOIUrl":"https://doi.org/10.1109/BIOCAS.2017.8325189","url":null,"abstract":"We present an algorithm and, for the first time, a chip to predict the neural theta oscillation phase, for closed-loop phase-locked stimulation triggering. The performance, assessed on test data recorded from human hippocampus, achieves high precision and accuracy in targeting any theta phase with 25%, 50%, and 75% of the predictions falling within ±13, ±28, and ±53 degrees from the desired target phase, respectively. Design interleaving channel-depth optimization achieves 41% energy and 58% area savings compared to a single-channel design. The 32-channel chip consumes a 216 nW per channel and occupies a core area of 0.011 mm2 per channel in a 40nm low-power technology, making it suitable for implantable devices.","PeriodicalId":361477,"journal":{"name":"2017 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132885944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bharath Ramesh, Ngoc Anh Le Thi, G. Orchard, C. Xiang
{"title":"Spike context: A neuromorphic descriptor for pattern recognition","authors":"Bharath Ramesh, Ngoc Anh Le Thi, G. Orchard, C. Xiang","doi":"10.1109/BIOCAS.2017.8325188","DOIUrl":"https://doi.org/10.1109/BIOCAS.2017.8325188","url":null,"abstract":"Although the neuromorphic vision community has developed useful event-based descriptors in the recent past, a robust general purpose descriptor that can handle scale and rotation variations has been elusive to achieve. This is partly because event cameras do not output frames at fixed intervals (like standard cameras) that are easy to work with, but an asynchronous sequence of spikes at microsecond to millisecond time resolutions. In this paper, we present Spike Context, a spatio-temporal neuromorphic descriptor that is inspired by the distribution of photo-receptors in the primate fovea. To demonstrate the effectiveness of the spike context descriptors, they are employed as semi-local features in the bag-of-features classification framework. In the first set of experiments on the N-MNIST dataset, we obtained very high results compared to existing works. In addition, we outperformed the state-of-the-art algorithms on the smaller MNIST-DVS dataset. Finally, we demonstrate the ability of the descriptor in handling scale variations by using the leave-one-scale-out protocol on the MNIST-DVS dataset.","PeriodicalId":361477,"journal":{"name":"2017 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130157072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Kremen, B. Brinkmann, Inyong Kim, Su-Youne Chang, J. Gompel, Jeffrey A. Herron, S. Baldassano, E. Patterson, B. Litt, T. Denison, G. Worrell
{"title":"Continuous active probing and modulation of neural networks with a wireless implantable system","authors":"V. Kremen, B. Brinkmann, Inyong Kim, Su-Youne Chang, J. Gompel, Jeffrey A. Herron, S. Baldassano, E. Patterson, B. Litt, T. Denison, G. Worrell","doi":"10.1109/BIOCAS.2017.8325195","DOIUrl":"https://doi.org/10.1109/BIOCAS.2017.8325195","url":null,"abstract":"The optimal epilepsy management device requires: 1) automated seizure detection 2) accurate automated electronic seizure diaries 3) seizure forecasting 4) active brain probing to track brain state and 5) automated brain stimulation therapy adjustment that can respond to changes in seizure probability to prevent seizures. In this paper, we describe an epilepsy management and therapy platform using Medtronic's investigational Activa RC+S Research System. The investigational Activa RC+S provides chronic nervous system stimulation, sensing, and embedded analytics. Continuous iEEG telemetry from the RC+S device can be received by a handheld or tablet computer providing more advanced analytical capability. The combined platform provides a unique opportunity for exploring and managing epileptic neurophysiology.","PeriodicalId":361477,"journal":{"name":"2017 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115003653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Ibrahim, Damien Doy, Claudio Loureiro, Eliéva Pignat, F. Angiolini, M. Arditi, J. Thiran, G. Micheli
{"title":"Inexpensive 1024-channel 3D telesonography system on FPGA","authors":"A. Ibrahim, Damien Doy, Claudio Loureiro, Eliéva Pignat, F. Angiolini, M. Arditi, J. Thiran, G. Micheli","doi":"10.1109/BIOCAS.2017.8325108","DOIUrl":"https://doi.org/10.1109/BIOCAS.2017.8325108","url":null,"abstract":"Volumetrie ultrasound (US) is a very promising development of medical US imaging. An under-exploited advantage of volumetric US is the mitigation of the strict probe positioning constrains necessary to acquire 2D scans, potentially allowing the decoupling of US image acquisition and diagnosis. However, today's 3D US systems are large and beset by high power and cost requirements, making them only available in well-equipped hospitals. In this study, we propose the first telesonography-capable medical imaging system that supports up to 1024 channels, on par with the state of the art. As a first embodiment, we have implemented our design in a single development FPGA board of 26.7cm×14cm×0.16cm, with an estimated power consumption of 6.1 W. Moreover, we have equipped our platform with an automatic positioning module to help any operator defining the scan location, hence allowing for better remote diagnosis. Our design supports two types of data inputs: real-time via an optical connection and offline over Ethernet. The reconstructed images can be visualized on an HDMI screen. The estimated cost of the proposed prototype materials is less than 4000€.","PeriodicalId":361477,"journal":{"name":"2017 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114661748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joseph L. Betthauser, Luke E. Osborn, R. Kaliki, N. Thakor
{"title":"Electrode-shift tolerant myoelectric movement-pattern classification using extreme learning for adaptive sparse representations","authors":"Joseph L. Betthauser, Luke E. Osborn, R. Kaliki, N. Thakor","doi":"10.1109/BIOCAS.2017.8325201","DOIUrl":"https://doi.org/10.1109/BIOCAS.2017.8325201","url":null,"abstract":"Myoelectric signal patterns can be used to predict the intended movements of amputees for prosthesis activation. Real-world prosthesis use introduces a variety of unpredictable conditional influences on these patterns, hindering the performance of classification algorithms and potentially leading to device abandonment. We have discovered a state-of-the-art classification method which is significantly more tolerant to these conditional influences. In our prior work, we presented a robust sparsity-based adaptive classification method that is tolerant to pattern deviations resulting from untrained limb positions and the prosthesis load. Herein, we demonstrate that this method is tolerant to the shifting or misalignment of the contact-electrode array which occurs during prosthesis use. We demonstrate the robustness of this approach in untrained electrode-site locations for amputee and able-bodied subjects, and report significant performance improvements over conventional myoelectric pattern recognition approaches. By showing that a single, unified method is robust across a variety of real-world condition spaces, clinicians are more likely to incorporate this method into myoelectric prosthesis controllers, resulting in improved utility and increased adoption among amputee users.","PeriodicalId":361477,"journal":{"name":"2017 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133584791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A 71% efficient energy harvesting and power management unit for sub-μW power biomedical applications","authors":"Abhishek Roy, B. Calhoun","doi":"10.1109/BIOCAS.2017.8325069","DOIUrl":"https://doi.org/10.1109/BIOCAS.2017.8325069","url":null,"abstract":"This paper presents an Energy Harvesting and Power Management Unit (EH-PMU) to power battery-less sub-μW systems-on-chip (SoCs) and wireless sensors for emerging Internet-of-Things (IoT) applications. The EH-PMU can harvest energy from either photovoltaic or thermoelectric sources and provides regulated outputs of 0.5V, 1V, and 1.8V. To reduce the power conversion overhead in < 1μW-power systems and thus to extend the system lifetime, the EH-PMU employs a hybrid architecture consisting of nW-quiescent power switched-capacitor DC-DC converters and low-dropout (LDO) regulators. The platform uses a 1.3nW gate-leakage based voltage reference generator, operational from 0.5V, along with Pulse Frequency Modulation (PFM) control to further lower the quiescent power of the switching regulators. The EH-PMU achieves a peak end-to-end efficiency of 71.1% while powering a 1 μW load in a 0.13μm chip.","PeriodicalId":361477,"journal":{"name":"2017 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132770708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuki Nagasato, S. Izumi, H. Kawaguchi, M. Yoshimoto
{"title":"Capacitively coupled ECG sensor system with digitally assisted noise cancellation for wearable application","authors":"Yuki Nagasato, S. Izumi, H. Kawaguchi, M. Yoshimoto","doi":"10.1109/BIOCAS.2017.8325162","DOIUrl":"https://doi.org/10.1109/BIOCAS.2017.8325162","url":null,"abstract":"This paper describes a digitally assisted noise cancellation method for a capacitively coupled electrocardiogram (ECG) sensor. This sensor using an insulated electrode can measure ECG through an insulator such as clothing without direct skin contact. In wearable applications, this type of ECG sensor is superior in terms of usability compared with the pasted type ECG sensor. However, noise immunity is an important difficulty related to capacitively coupled ECG sensors because it requires very high input impedance and small input capacitance for the first-stage amplifier. This circuit characteristic considerably degrades its noise immunity for the power line noise and motion artifact. To address this difficulty, we propose the noise feedback method, which can improve the availability of a capacitively coupled ECG sensor. Noise caused by body movement and the surrounding environment included in the output of the AD converter is extracted by digital filters. DC offset, baseline fluctuation, and low-frequency component of body motion noise are extracted using a variable-gain loop filter. Power line noise is also extracted using a peak filter. Then the noise waveform is estimated from the result of the previous cycle. This noise information is DA converted and given feedback to the first stage amplifier. The proposed method was evaluated using prototype sensor in an actual environment. ECG measurements were confirmed in both two-electrode configuration and single-electrode configuration. Measurement results show that the power line noise can be suppressed to −29.2 dB at maximum.","PeriodicalId":361477,"journal":{"name":"2017 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"186 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116192245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Takaaki Okano, S. Izumi, H. Kawaguchi, M. Yoshimoto
{"title":"Non-contact biometric identification and authentication using microwave Doppler sensor","authors":"Takaaki Okano, S. Izumi, H. Kawaguchi, M. Yoshimoto","doi":"10.1109/BIOCAS.2017.8325160","DOIUrl":"https://doi.org/10.1109/BIOCAS.2017.8325160","url":null,"abstract":"As described in this paper, we propose a non-contact biometrie authentication method with heartbeat features measured using a microwave Doppler sensor. The heartbeat component is measured as personal characteristic information attributable to individual differences in the myocardium and blood vessels. Biometric authentication using electrocardiogram (ECG) or pulse wave has been proposed in reports of earlier studies, but such methods require direct contact of the sensor with the human skin. However, heartbeat information can be measured and authenticated without contact to the skin when using the proposed method. The microwave Doppler sensor can detect minute vibrations of the body surface caused by heartbeat. The salient difficulty of the microwave Doppler sensor is noise contamination such as that caused by body motion. This study introduces the use of time-frequency analysis with an autoregressive model to reduce the noise influence and emphasize heartbeat features. An ID generation and authentication algorithm using a frequency feature of the heartbeat component is proposed. The proposed method was evaluated using measurements taken of 11 participants. Measurement results show a 92.8% true acceptance rate and a 3.9% equal error rate.","PeriodicalId":361477,"journal":{"name":"2017 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125152011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Li Jing Ong, Marshal Dian Sheng Wong, Shih-Chiang Liu, Astrid Rusly, C. Tsai, Khay-Wai Leong, K. Ng, R. Jegadeesan, K. Voges, N. Thakor, S. Yen, S. Nag
{"title":"Live demonstration: Programmable biphasic multi-channel constant current muscle stimulator with wireless power and data transfer","authors":"Li Jing Ong, Marshal Dian Sheng Wong, Shih-Chiang Liu, Astrid Rusly, C. Tsai, Khay-Wai Leong, K. Ng, R. Jegadeesan, K. Voges, N. Thakor, S. Yen, S. Nag","doi":"10.1109/BIOCAS.2017.8325095","DOIUrl":"https://doi.org/10.1109/BIOCAS.2017.8325095","url":null,"abstract":"We have developed a fully implantable 4-channel wireless muscle stimulator system with the ability to elicit precise and graded muscle movements for a hand grasping motion. The stimulator system consists of a WiFi enabled inductive powering and data transfer circuitry connected to a laptop, and a wireless implantable stimulator unit with biocompatible stainless steel electrodes. We shall demonstrate this stimulator package and its features through a dummy robotic rat limb. We will also show videos of the stimulator being used to activate the rodent hind limb muscles to kick a ball, and activate the forearm muscles of a non-human primate to elicit individual finger movement to play a virtual piano.","PeriodicalId":361477,"journal":{"name":"2017 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129548238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Takezawa, K. Kiyoyama, K. Shimokawa, Z. Qian, H. Kino, T. Fukushima, Tetsu Tanaka
{"title":"Ultrawide range square wave impedance analysis circuit with ultra-slow ring-oscillator using gate-induced drain-leakage current","authors":"Y. Takezawa, K. Kiyoyama, K. Shimokawa, Z. Qian, H. Kino, T. Fukushima, Tetsu Tanaka","doi":"10.1109/BIOCAS.2017.8325165","DOIUrl":"https://doi.org/10.1109/BIOCAS.2017.8325165","url":null,"abstract":"This paper presents area efficient and ultrawide range square wave impedance analysis circuit for biomedical applications. By using a gate-induced drain-leakage current (GIDL), we designed an ultralow current generation circuit which is a key component of the impedance measurement circuit and a GIDL-controlled oscillator operating at ultralow frequency. In addition, the area of the impedance measurement circuit becomes remarkably small due to square waveform current. All impedance measurement circuits are fabricated with a 0.18μm 1P6M standard CMOS technology and occupy 0.43mm2. As results, the proposed GIDL-controlled oscillator circuit successfully oscillated at ultralow frequency of 3.1Hz, and the impedance measurement circuit completely outputs square waveforms with a current amplitude of 50pA. The proposed circuit can measure impedance ranges from 100Ω to 100MΩ.","PeriodicalId":361477,"journal":{"name":"2017 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129633961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}