| 1. |
- Bao, D., et al.
(författare)
-
A smart catheter system for minimally invasive brain monitoring
- 2015
-
Ingår i: Proceedings of the International Conference on Biomedical Electronics and Devices. - : SciTePress. - 9789897580710 ; , s. 198-203
-
Konferensbidrag (refereegranskat)abstract
- This paper demonstrates a smart catheter system with intracranial pressure (ICP) and temperature sensing capability which is designed for real-time monitoring in traumatic brain injury (TBI) therapy. It uses a single flexible catheter with a 1 mm (3 Fr) diameter that integrates electrodes and sophisticated silicon chip on flexible substrates, enabling multimodality monitoring of physiological signals. A micro-electromechanical-system (MEMS) catheter pressure sensor is mounted on the distal end. It can be used for detecting both pressure and temperature by different switch configurations, which minimizes the size of catheter and reduces the cost. The interconnects (signalling conductors) are printed on a bio-compatible flexible substrate, and the sensor is interfaced with an embedded electronic system at the far-end. The electronic system consists of analog front end with analog-to-digital converter (ADC), a microcontroller, and data interface to the hospital infrastructure with a graphical user interface (GUI). The overall smart catheter system achieves a pressure sensing root mean square error (RMSE) of ±1.5 mmHg measured from 20 mmHg to 300 mmHg above 1 atm and a temperature sensing RMSE of ±0.08°C measured from 32°C to 42°C. The sampling rate can be up to 10S/s. The in vivo performance is demonstrated in laboratory animals.
|
|
| 2. |
- Zhai, Chuanying, et al.
(författare)
-
A 2.4-GHz ISM RF and UWB hybrid RFID real-time locating system for industrial enterprise Internet of Things
- 2017
-
Ingår i: Enterprise Information Systems. - : Taylor & Francis. - 1751-7575 .- 1751-7583. ; 11:6, s. 909-926
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents a 2.4-GHz radio frequency (RF) and ultra-wide bandwidth (UWB) hybrid real-time locating system (RTLS) for industrial enterprise Internet of Things (IoT). It employs asymmetric wireless link, that is, UWB radio is utilised for accurate positioning up to 10 cm in critical sites, whereas 2.4-GHz RF is used for tag control and coarse positioning in non-critical sites. The specified communication protocol and the adaptive tag synchronisation rate ensure reliable and deterministic access with a scalable system capacity and avoid unpredictable latency and additional energy consumption of retransmissions due to collisions. The tag, consisting of a commercial 2.4-GHz transceiver and a customised application-specific integrated circuit (ASIC) UWB transmitter (Tx), is able to achieve up to 3 years’ battery life at 1600 tags per position update second with 1000 mAh battery in one cluster. The time difference of arrival (TDoA)–based positioning experiment at UWB radio is performed on the designed software-defined radio (SDR) platform.
|
|
| 3. |
- Zhai, Chuanying, et al.
(författare)
-
A Software Defined Radio platform for passive UWB-RFID localization
- 2012
-
Ingår i: 2012 IEEE International Conference on Wireless Information Technology and Systems, ICWITS 2012. - : IEEE. - 9781467309486 ; , s. 6417741-
-
Konferensbidrag (refereegranskat)abstract
- Radio-Frequency-Identification (RFID) with high sensing and positioning capability is the key technology enabler for the vision of the context-aware and location-aware computing towards the Internet-of-Things. However, the existing passive RFID in Ultra-High-Frequency (UHF) based on backscattering scheme can only provide limited ranging resolution and insufficient localization accuracy. Besides, it is sensitive to narrowband interference and multipath environment. Alternatively, Ultra-Wideband (UWB) has been recognized as a promising technology for the next generation RFIDs [1,2]. The Impulse-radio UWB (IR-UWB) implementations employ sub-nanosecond duration pulses without carrier, thus significantly reducing hardware complexity and power consumption. The wideband of the signals provide the potential of fine resolution in dense multipath scenarios. As one of the most attractive characteristics, UWB RFID potentially provides centimeter-level localization accuracy thanks to the ultrashort pulses with high time domain resolution by using time-of-arrival (ToA) estimation of the signal. There has been many works using UWB as active RFID tags for positioning and tracking application [3,4]. Moreover, in order to introduce UWB to passive RFID systems, UHF powered UWB-RFID system with asymmetric links has been proposed in [5]. Based on this UHF/UWB hybrid architecture, the positioning feasibility and ToA estimation has been studied in [6] in algorithm level.
|
|
| 4. |
- Zhai, Chuanying, et al.
(författare)
-
Software defined radio IR-UWB positioning platform for RFID and WSN application
- 2012
-
Ingår i: Ultra-Wideband (ICUWB), 2012 IEEE International Conference on. - : IEEE. - 9781457720307 ; , s. 501-505
-
Konferensbidrag (refereegranskat)abstract
- This paper presents a software defined radio (SDR) platform for Impulse Ultra-Wideband (IR-UWB) sensing and positioning applications. The platform is composed by a software simulator (SW) and a hardware testbed (HW). The software simulator based on Matlab offers reconfigurable modules/functions of UWB systems with a graphic user interface (GUI). Correspondingly, the testbed is implemented by an oscilloscope and a set of off-the-shelf components. The oscilloscope (Lecroy WaveMaster 816Zi-A) features high-speed real-time sampling (i.e., 40 GS/s with 16 GHz analog bandwidth) with 4 independent channels, enabling a multi-antenna multichannel receiver network in UWB bands, with signal processing capability at the Nyquist rate. The SW and HW are seamlessly integrated by the build-in software in the oscilloscope. It allows rapid prototypes of various algorithms to be verified in real environments. Finally, a case study on UWB ranging for localization is given to demonstrate the feasibility and usability of the proposed platform.
|
|
| 5. |
- Zou, Zhuo, et al.
(författare)
-
Design and demonstration of passive UWB RFIDs : Chipless versus chip solutions
- 2012
-
Ingår i: RFID-Technologies and Applications (RFID-TA), 2012 IEEE International Conference on. - : IEEE. - 9781467346566 ; , s. 6-11
-
Konferensbidrag (refereegranskat)abstract
- This paper reviews recent research on Ultra-Wideband (UWB) techniques for the next generation Radio Frequency IDentification (RFID) towards the Internet-of-Things (IoT), conducted by Vinn iPack Center at KTH, Sweden. First, we introduce an inkjet printed chipless UWB RFID for ultra-low cost applications such as item-level tracking. The identification number is coded by variations of the impedance over the transmission line, resulting in the OOK modulated data by means of pulse reflections in time domain. Prototypes were fabricated and measured for 4-bit tag and 8-bit tag, respectively. Thanks to the employment of fully printing process and paper substrates, the tag is potentially ultra-low cost in volume production. Second, a wirelessly powered RFID tag with an active UWB transmitter is studied for advanced applications such as wireless positioning and sensing. The tag is powered by UHF continuous waves, whereas it uses an UWB pulse generator to transmit data to the reader. It ensures the improved coverage and accurate positioning over traditional backscattering UHF tags. UWB readers, positioning, and sensing are also discussed in a system perspective. The two solutions reveal that UWB is a viable alternative to existing passive RFIDs adapting both low-cost applications and high-performance sensing and positioning applications.
|
|
