| 1. |
- Baghaei Nejad, Majid, et al.
(författare)
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A novel passive tag with asymmetric wireless link for RFID and WSN applications
- 2007
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Ingår i: 2007 IEEE INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS. - 9781424409204 ; , s. 1593-1596
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Konferensbidrag (refereegranskat)abstract
- In this paper, we present a radio-powered module with asymmetric wireless link utilizing ultra wideband radio system for RFID and wireless sensor applications. Our contribution includes using two different standards in uplink and downlink. Such as conventional RFIDs, incoming RF signal transmitted by reader is used to power the internal circuitry and receive the data. However, in upstream link, an IR-UWB transmitter is utilized. Unlike traditional RFID systems, due to great advantages of UWB communication, this tag is very robust to multi-path fading and collision problem and it is more secure against eavesdropping or jamming. The module consists of a power scavenging unit, a RF receiver, an IR-UWB transmitter, digital baseband controller, and an embedded UWB antenna are designed for integration on Liquid-Crystal Polymer (LCP) substrate, using 0.18um CMOS process technology.
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| 2. |
- Baghaei Nejad, Majid, et al.
(författare)
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A remote-powered RFID tag with 10Mb/s UWB Uplink and -18.5dBm sensitivity UHF downlink in 0.18μm CMOS
- 2009
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Ingår i: Digest of technical papers / IEEE International Solid-State Circuits Conference. - 0193-6530. ; , s. 198-199,199a
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Tidskriftsartikel (refereegranskat)abstract
- In this work, a 10 Mb/s impulse UWB RFID tag in 0.18 mum CMOS is presented. The tag is remotely powered by a UHF signal with a minimum input RF power as low as 14.1 muW. The primary innovation is to employ two different communication links (UWB and UHF) respectively in the uplink and downlink of the tag. This is because the amount of data or instructions from a reader to a tag is small and as a result a conventional UHF-RFID link at 900MHz can be used as the downlink. The UHF signal also provides remote power to the tag. The uplink requires higher data rates and precise positioning capability therefore an l-UWB transmitter is employed.
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| 3. |
- Baghaei Nejad, Majid, et al.
(författare)
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Enabling Ubiquitous Wireless Sensing by a Novel RFID-Based UWB Module
- 2007
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Ingår i: The First International EURASIP Workshop on RFID Technology, RFID 2007, 24-25 September 2007, Vienna, Austria.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In this paper, we present a novel passive CMOS module which uses two different standards in uplink and downlink. It can be used in many applications such as Radio Frequency Identification (RFID), and ubiquitous wireless sensing. Such as conventional RFID systems, the module captures power supply from received RF signal transmitted by a reader and extracts data and clock by using an envelope detector and PIE encoder. However, in uplink instead of back scattering, an Impulse-UWB transmitter is used to improve the system performance and throughput. The UWB communication offers several advantages to the system. A new communication protocol is proposed for the system based on slotted-ALOHA anti-collision algorithm. The module consisting of a power management unit, an RF narrowband receiver, a clock management unit, an IR-UWB transmitter, and a digital baseband are designed in 0.18 CMOS process.
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| 4. |
- Zheng, Lirong, et al.
(författare)
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Future RFID and Wireless Sensors for Ubiquitous Intelligence
- 2008
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Ingår i: 26th Norchip Conference, Norchip. ; , s. 142-149
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Konferensbidrag (refereegranskat)abstract
- Next generation RFID towards ubiquitous wireless sensing and identification requires high network throughput along with long operation range and ultra low energy consumption. In this paper, we review future RFID for ubiquitous intelligence and their technology needs from system to device perspectives. As a promising enabling technology, ultra wideband radio (UWB) and its use in various RFID implementations are investigated. A special focus on an UWB/UHF hybrid passive RFID and sensor system with asymmetric wireless links is studied as an example. Unlike conventional RFID systems relying on backscattering and narrowband radio, UWB is introduced as the uplink for tag to reader communication. It enables a high network throughput (2000 tag/sec), high data bandwidth (100MHz pulse rate), under ultra low power and low cost constraint. The hardware implementation in silicon level is also presented. Finally, applications of the system in intelligent warehouse and fresh food tracker are introduced.
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| 5. |
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| 6. |
- Zou, Zhuo, et al.
(författare)
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A digital back-end of energy detection UWB impulse radio receiver
- 2009
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Ingår i: NORCHIP, 2009. - 9781424443109
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Konferensbidrag (refereegranskat)abstract
- This paper presents a digital back-end design for energy detection IR-UWB receivers which can be adopted in RFID and wireless sensor applications. A baseband processor is designed on the basis of a novel synchronization and estimation algorithm. It reduces implementation complexity and energy consumption. A programmable timing circuitry with 1.04 ns phase resolution is also devised in this work. The digital back-end is implemented in UMC 90 nm process, with 222 uW power and 140*220 um2 die area.
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| 7. |
- Zou, Zhuo, et al.
(författare)
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An efficient passive RFID system for ubiquitous identification and sensing using impulse UWB radio
- 2007
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Ingår i: Elektrotechnik und Informationstechnik. - : Springer Science and Business Media LLC. - 0932-383X. ; 124:11, s. 397-403
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Tidskriftsartikel (refereegranskat)abstract
- The next generation RFID system for ubiquitous identification and sensing requires both energy and system efficiency. This paper describes an efficient passive RFID system using impulse ultra-wideband radio (IR-UWB), at a 10 m operation range. Unlike conventional passive RFID systems which rely on backscatter and narrowband radio, IR-UWB is introduced as the uplink (communication from a tag to a reader). By utilizing a specialized communication protocol and a novel ALOHA-based anti-collision algorithm, such semi-UWB systems enable a high network throughput (2000 tag/sec) under the low power and low cost constraint. A low power tag design for proof of concept is finally presented.
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| 8. |
- Zou, Zhuo, et al.
(författare)
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Baseband design for passive semi-UWB wireless sensor and identification systems
- 2007
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Ingår i: Proceedings - 20th Anniversary IEEE International SOC Conference. - 9781424415922 ; , s. 313-316
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Konferensbidrag (refereegranskat)abstract
- This paper presents a digital baseband design for passive sensor and identification systems using asymmetric wireless links with ultra wideband (UWB) radio. As opposed to traditional wireless sensor and identification systems using halfduplex communication in narrowband frequency, impulse-LTWB is applied as an uplink in the proposed system. A novel baseband protocol is devised to improve the system efficiency in the multitag environment while maintaining the power constraint. By utilizing adaptive slotted ALOHA anti-collision algorithm, 1000 tags can be processed within 5OOms. The contributions also include the development of a low-power digital baseband processor for passive tags. The simulation is successful and the FPGA prototype is operational. The chip is implemented for ASIC and it Kill be fabricated and tested Kith the front-end in IP6M UMC 0. 18 mu m process.
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| 9. |
- Zou, Zhuo, et al.
(författare)
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Impulse UWB Energy Detection Receiver with Energy Offset Synchronization Scheme
- 2009
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Ingår i: 2009 IEEE INTERNATIONAL CONFERENCE ON ULTRA-WIDEBAND (ICUWB 2009). - NEW YORK : IEEE. - 9781424429301 ; , s. 540-544
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Konferensbidrag (refereegranskat)abstract
- Impulse ultra-wideband radios (IR-UWB) show strong advantages in low power and low cost applications such as RFIDs and wireless sensor networks. This paper presents an IR-UWB receiver based on Energy Detection (ED) with on-off keying (OOK) modulation. A novel synchronization and detection algorithm using the energy offset scheme with adaptive threshold detection is suggested, aiming to reduce energy consumption and simplify hardware complexity. Simulation and FPGA implementation reveal that the proposed method can avoid complex and power consuming synchronization blocks, and reduce the preamble length, whereas maintaining the performance in the target level. Hardware integration issues are discussed, implying that the proposed receiver architecture has the possibility to achieve low complexity and low power implementation with several nJs energy per bit, at a data rate of 10Mb/s.
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