440 research outputs found
Antennas for wide area distributed RFID systems
© 2020 IEEE. This paper describes the use of Wide Area Distributed RFID Systems to enable wide area coverage of UHF RFID with high likelihood of tags anywhere within the area being successfully detected. The implications on antenna design are discussed and novel loop antenna meeting the requirements is presented
Coexistence of high-bit-rate quantum key distribution and data on optical fiber
Quantum key distribution (QKD) uniquely allows distribution of cryptographic
keys with security verified by quantum mechanical limits. Both protocol
execution and subsequent applications require the assistance of classical data
communication channels. While using separate fibers is one option, it is
economically more viable if data and quantum signals are simultaneously
transmitted through a single fiber. However, noise-photon contamination arising
from the intense data signal has severely restricted both the QKD distances and
secure key rates. Here, we exploit a novel temporal-filtering effect for
noise-photon rejection. This allows high-bit-rate QKD over fibers up to 90 km
in length and populated with error-free bidirectional Gb/s data communications.
With high-bit rate and range sufficient for important information
infrastructures, such as smart cities and 10 Gbit Ethernet, QKD is a
significant step closer towards wide-scale deployment in fiber networks.Comment: 7 pages, 5 figure
Recommended from our members
Performance Analysis of Passive UHF RFID Systems under Cascaded Fading Channels and Interference Effects
In this paper, the performance of monostatic and
bistatic passive ultrahigh-frequency radio-frequency identification
(UHF RFID) systems under the effects of cascaded fading
channels and interference is studied. The performance metric
used is tag detection probability defined as probability that the
instantaneous received power is higher than the receiver’s sensitivity.
A closed-form expression of the detection probability is
derived using cascaded forward and backscatter fading channels
and reader antennas orientation. Furthermore, the performance
of passive RFID systems under reader-to-tag interference caused
by both the desired RFID signal and multiple RFID interferers
is analyzed, and the effect of constructive and destructive
interferences is examined. In addition, the maximum reading
range in ideal, multipath fading and interfering environments is
presented. The obtained results are very useful for the design and
optimization of passive RFID systems from RF point of view.This work was made possible by NPRP grant NPRP4-726-2-272 from
the Qatar National Research Fund (a member of Qatar Foundation).This is the accepted manuscript. The final version is available from IEEE at http://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber=6942226
Advanced photonic routing sub-systems with efficient routing control
In recent years, there has been much interest in the development of optical switches which can route optical signals from different input guides to different outputs based on thermo-optic and electro-optic technologies. Such switches, which can be reconfigured on millisecond and microsecond timescales, have already attracted commercial interest. However switches which are able to reconfigure on the nanosecond timescales required for packet switching have been more challenging and only in recent years, have router concepts been devised to allow lossless routers to be constructed able to switch on nanosecond timescales with more than 16×16 ports. This paper will therefore review the advances that have occurred to allow such operation and then describe recent studies that have begun to determine the electronic control and functionality required to enable full and practical operation of such switches in high performance networks.This research has received funding from the UK Engineering and Physical Sciences Research Council through the INTERNET Project, STAR and COPOS II grants and the European Commission under FP7 grant agreement ICT 257210 PARADIGM.This is the author accepted manuscript. The final version is available from IEEE via http://dx.doi.org/10.1109/ICTON.2015.719339
Low-energy, high-performance lossless 8×8 SOA switch
We demonstrate the first monolithically-integrated active-passive lossless 8×8 SOA
switch. A wide IPDR of 14.5dB for penalty <1dB is achieved. The switch paths through the device
exhibit excellent uniformity.The research leading to these results has received funding from the UK EPSRC through the
INTERNET, STAR and COPOS II grants and the European Commission under FP7 grant agreement ICT 257210
PARADIGM.This is the accepted manuscript. The final version is available from OSA at http://www.opticsinfobase.org/abstract.cfm?uri=OFC-2015-Th4E.6
Recommended from our members
Demonstration of the feasibility of large-port-count optical switching using a hybrid Mach-Zehnder interferometer-semiconductor optical amplifier switch module in a recirculating loop.
For what we believe is the first time, the feasibility of large-port-count nanosecond-reconfiguration-time optical switches is demonstrated using a hybrid approach, where Mach-Zehnder interferometric (MZI) switches provide low-loss, high-speed routing with short semiconductor optical amplifiers (SOAs) being integrated to enhance extinction. By repeatedly passing signals through a monolithic hybrid dilated 2×2 switch module in a recirculating loop, the potential performance of high-port-count switches using the hybrid approach is demonstrated. Experimentally, a single pass switch penalty of only 0.1 dB is demonstrated for the 2×2 module, while even after seven passes through the switch, equivalent to a 128×128 router, a penalty of only 2.4 dB is recorded at a data rate of 10 Gb/s.This is the author accepted manuscript. The final version is published in Optics Letters - http://www.opticsinfobase.org/ol/abstract.cfm?uri=ol-39-18-5244
Demonstration of a lossless monolithic 16x16 QW SOA switch
10Gb/s error-free operation of the first monolithic 16×16 quantum well semiconductor optical amplifier switch is demonstrated. The switch has a 2dB facet-to-facet gain and a minimum power penalty of 2.5dB
- …