A novel ultra-high-frequency (UHF) RFID reader antenna with 2 dimensional (2D) beam-scanning capability and a wide 3 dB axial ratio (AR) beamwidth of over 136 • is presented. The proposed antenna consists of three concentric metal rings, each having a branch wire to stimulate circular polarization (CP) and a separate feed. The antenna is able to perform a 2D beam-scan with a relatively stable gain (9-11 dBic) from 0 • to 360 • in azimuth, and-40 • to 40 • in zenith. The minima of the antenna's AR beamwidth follows the peak gain direction, giving an equivalent 3 dB AR beamwidth of 136 • for every phi cut, wider than current state-of-the-art [1]. Moreover, the proposed antenna array presents a 50Ω impedance with no impedance matching network, and requires only two phase shifters to steer, significantly reducing the design complexity. The antenna's-10 dB return loss bandwidth is from 843 MHz to 880 MHz, covering the lower band UHF RFID frequencies in the European Telecommunications Standards Institute (ETSI) region.

We present an experimental demonstration of the feasibility of the first 20 + Mb/s Gaussian modulated coherent state continuous variable quantum key distribution system with a locally generated local oscillator at the receiver (LLO-CVQKD). To increase the signal repetition rate, and hence the potential secure key rate, we equip our system with high-performance, wideband devices and design the components to support high repetition rate operation. We have successfully trialed the signal repetition rate as high as 500 MHz. To reduce the system complexity and correct for any phase shift during transmission, reference pulses are interleaved with quantum signals at Alice. Customized monitoring software has been developed, allowing all parameters to be controlled in real-time without any physical setup modification. We introduce a system-level noise model analysis at high bandwidth and propose a new ‘combined-optimization’ technique to optimize system parameters simultaneously to high precision. We use the measured excess noise, to predict that the system is capable of realizing a record 26.9 Mb/s key generation in the asymptotic regime over a 15 km signal mode fibre. We further demonstrate the potential for an even faster implementation.

RFID has been used in the aviation industry to track and identify emergency equipment and other in-cabin assets on commercial aircraft for some time. Recently, the industry is looking to expand the use of RFID to more demanding parts and surfaces both inside and outside of an aircraft's cabin, where RFID tags face much harsher conditions. The landing gear (LG) is one of the critical subsystems of an aircraft that plays an essential role in dispersing the energy of landing events and taxiing. Health monitoring of the LG has been suggested to help reduce both operational and maintenance costs, and extend the life of the LG beyond its current, fixed, designed service life. In this paper, we propose a health monitoring system using a combination of active wired sensors and passive RFID tags. We present the measurement of Ultra-high Frequency (UHF) RFID tags on an aircraft landing gear using an aircraft-mounted fixed RFID reader. The results indicate that all major landing gear components and assemblies are shown to be identifiable by their EPC, and a 7 dB system margin has been achieved using 2 RFID reader antennas. Such a margin will tolerate degradations caused by harsh environments (e.g. low temperatures and high humidity) and enable update of information (e.g. flight count) stored on the RFID tags.

We experimentally demonstrate a 250MHz repetition rate Gaussian-modulated coherentstate CVQKD with local local oscillator implementation which is capable of realizing record 14.2 Mbps key generation in the asymptotic regime over 15km of optical fiber.

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A novel ultra-high-frequency (UHF) RFID reader antenna is proposed. The antenna has a unique property as being able to change its axial ratio (AR) without affecting its gain, beamwidth or impedance matching performance, enabling the isolated study of the effect of different axial ratios in RFID tag reading.

A novel ultra-high-frequency (UHF) RFID reader antenna with 2 dimensional (2D) beam-scanning capability and a wide 3 dB axial ratio (AR) beamwidth of over 136 • is presented. The proposed antenna consists of three concentric metal rings, each having a branch wire to stimulate circular polarization (CP) and a separate feed. The antenna is able to perform a 2D beam-scan with a relatively stable gain (9-11 dBic) from 0 • to 360 • in azimuth, and-40 • to 40 • in zenith. The minima of the antenna's AR beamwidth follows the peak gain direction, giving an equivalent 3 dB AR beamwidth of 136 • for every phi cut, wider than current state-of-the-art [1]. Moreover, the proposed antenna array presents a 50Ω impedance with no impedance matching network, and requires only two phase shifters to steer, significantly reducing the design complexity. The antenna's-10 dB return loss bandwidth is from 843 MHz to 880 MHz, covering the lower band UHF RFID frequencies in the European Telecommunications Standards Institute (ETSI) region.