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oe1(光电查) - 科学论文

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  • Interplay of Bit Rate, Linewidth, Bandwidth, and Reach on Optical DMT and PAM with IMDD

    摘要: We theoretically compare the performance of optical discrete multi-tone (DMT) and pulse amplitude modulation (PAM) using intensity modulated, direct detection (IMDD). PAM is a lower cost, lower complexity solution than DMT, however it is more vulnerable to chromatic dispersion on the C band. We compare DMT and PAM taking into consideration the interplay of laser linewidth, fiber length, transmission rate, and channel bandwidth. We use a semi-analytical model to examine bit error rates. We study how system parameters shift the performance advantages between DMT and PAM. Our model can also be used to find the best hardware solution and frequency band for a target modulation format and bit error rate.

    关键词: PAM,O-band,C-band,chromatic dispersion,DMT,bandwidth,laser linewidth

    更新于2025-09-23 15:22:29

  • [Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - Compact L/S-Band Circularly Polarized Microstrip Antenna over Reactive Impedance Surface

    摘要: A compact LIS-band circularly polarized (CP) antenna over the reactive impedance surface (RIS) is designed, fabricated, and measured. This dual-band CP antenna is excited by two probes and fed by two grounded coplanar waveguides. The CP radiation with very compact antenna size is achieved by stacking a square ring slotted truncated corner square patch and a truncated corner square patch over the RIS. The measured results show that the 3-dB axial ratio bandwidth of the antenna is 0.9% (1.787-1.803 GHz) for the lower band and 1.1% (2.685-2.715 GHz) for the upper band, while the 10-dB return loss bandwidth is 5.9% (1.746-1.852 GHz) and 7.3% (2.586-2.784 GHz), respectively. The antenna gain at boresight is 1.9 dBic for the lower band, and 1.94 dBic for the upper band. The overall volume of the dual-band CP antenna is 0.235 x 0.235 x 0.042λ at 1.765 GHz.

    关键词: reactive impedance surface,circularly polarized antenna,size miniaturization,dual band

    更新于2025-09-23 15:22:29

  • [IEEE 2018 19th International Conference on Electronic Packaging Technology (ICEPT) - Shanghai (2018.8.8-2018.8.11)] 2018 19th International Conference on Electronic Packaging Technology (ICEPT) - Graphene-like Monolayer Yttrium Nitride: A Moderate Semiconductor and Pronounced Electronic Insensitivity to Strain

    摘要: It is extremely important to explore two-dimensional materials with excellent properties due to their potential applications in future electronic devices. In the present study, a 2D hexagonal YN (h-YN) is predicted based on theoretical calculations. By assessing the phonon spectrum, ab initio molecule dynamics and elastic constants, the h-YN monolayer is proved to own satisfying thermal, dynamic and mechanical stability. Distinguishing from the most reported 2D transition metal mononitrides which exhibit metallic, monolayer h-YN presents a semiconducting characteristic with a indirect bandgap of 1.144 eV. In particular, h-YN presents unusually insensitive responses of electronic structures to tensile or compressive strain due to the valence orbital hybridization. Moderate bandgap together with insensitive electronic responses to strain endow h-YN a promising candidate in future nanoscale electronic devices in high-strain conditions.

    关键词: nano-electronics,strain condition,band structure,two-dimensional

    更新于2025-09-23 15:22:29

  • [IEEE 2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Chengdu, China (2018.5.7-2018.5.11)] 2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - A 300GHz Monolithic Integrated Amplifier in 0.5-μm InP Double Heterojunction Bipolar Transistor Technology

    摘要: We present a compact, 6-stage terahertz monolithic integrated circuit (TMIC) amplifier with an operating frequency of 275-310GHz, formed by common-base configured 0.5 um InP Double Heterojunction Bipolar Transistor (DHBT) and a multilayer thin-film microstrip (TFM) wiring environment. The amplifier small signal gain exhibits >7.4dB at 300GHz. The peak gain is 12.5dB at 280GHz. This is the first time reported InP DHBT TMIC amplifier operating in H-band employing TFM in china. The total size of this 6-stage amplifier is only 1.7 mm ╳0.9 mm.

    关键词: thin-film microstrip (TFM),Indium phosphide (InP),H-band,Amplifier,Heterojunction bipolar transistors (HBTs),Terahertz monolithic integrated circuit (TMIC)

    更新于2025-09-23 15:22:29

  • [IEEE 2018 IEEE CPMT Symposium Japan (ICSJ) - Kyoto, Japan (2018.11.19-2018.11.21)] 2018 IEEE CPMT Symposium Japan (ICSJ) - Study on corundum-structured p-type iridium oxide thin films and band alignment at iridium oxide /gallium oxide hetero-junction

    摘要: Corundum-structured iridium oxide, showing p-type conductivity, is a powerful candidate material for forming high-quality pn hetero-junctions with gallium oxide. We have succeeded in fabricating corundum-structured iridium oxide thin films on sapphire substrates. According to the optical transmittance measurement, the optical bandgap of iridium oxide was found to be approximately 3.0 eV. Furthermore, the band alignment at the iridium oxide /gallium oxide interface was investigated by X-ray photoemission spectroscopy, revealing a staggered-gap (type-Ⅱ) with the valence and conduction band offsets of 3.3 eV and 1.0 eV, respectively.

    关键词: p-type oxide semiconductor,band alignment,gallium oxide

    更新于2025-09-23 15:22:29

  • A Square-Root-Based Memory Polynomial Model for Concurrent Dual-Band Digital Predistortion

    摘要: In this letter, a novel 2-D square-root-based memory polynomial behavioral model is proposed. A new set of square-root-based basic functions is adopted to describe the characteristic of the predistorter. Since the proposed model has only two nested summations, the number of coefficients of the proposed model is greatly reduced compared with models which have three nested summations. The experimental results show that the proposed model can reduce the coefficients by more than 66.7% compared with the 2-D digital predistortion (2D-DPD) model. Moreover, the proposed model can achieve better adjacent channel power ratio (ACPR) performance. Compared with the 2D-DPD model and the simple online coefficient update model, the proposed model can improve the normalized mean-square error by 11 dB. Compared with the 2-D modified memory polynomial model, the proposed model can obtain similar ACPR performance with a shorter running time.

    关键词: power amplifiers (PAs),Digital predistortion (DPD),dual band

    更新于2025-09-23 15:22:29

  • [IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - L-Band Radar Sounder for Measuing Ice Basal Conditions and Ice-Shelf Melt Rate

    摘要: A new L-band radar system is proposed to measure ice thickness, basal conditions and ice-shelves bottom melt rates. The concept for ice measurements with an L-band radar is based on the recent success in sounding shallow low-loss ice (< 1 km) and measuring ice-self melt rates with a 600-900 MHz low-power radar, referred to as accumulation radar [1]. A surface-based radar operating over 1.2-1.4 GHz with a peak transmit power of 2 kW is proposed to sound and image more than 4 km thick ice. The higher frequency at 1.3 GHz will provide the sensitivity required to detect basal water film as thin as 0.5 mm as compared to radars operating now at frequencies less than 600 MHz. These radars need a minimum film thickness of 4 mm or more for reliable detection. The proposed L-band radar will also measure the bottom melt rate of ice shelves. The current plan is to deploy the proposed radar for field test in Antarctica during the 2018-2019 field season.

    关键词: L-band,sounder,ice,Radar

    更新于2025-09-23 15:22:29

  • [IEEE 2018 IEEE International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM) - Nagoya (2018.8.29-2018.8.31)] 2018 IEEE International Workshop on Electromagnetics:Applications and Student Innovation Competition (iWEM) - Dual-Strip Monopole Antenna for USB Dongle Applications

    摘要: In the paper, a design of dual-path folded monopole antenna for WLAN bands and 5G C-Band on dongle devices is presented. The antenna occupies an overall size of 30 × 10 × 4.8 mm3; the size of ground plane is 25 × 10 mm2. A Dual-strip monopole antenna with two bending plates to from a 3D structure excites the WLAN band and 5G C-band for USB dongle devices. The measured and simulated S11 of the antenna can be applied to WLAN bands (2.4 — 2.484, 5.15 — 5.35, and 5.725 — 5.825 GHz), 5G C-band (3.4 — 3.6 GHz). The more results of the antenna will be proposed and discussed in the paper.

    关键词: USB,C-band,Dongle,WLAN antenna

    更新于2025-09-23 15:22:29

  • Propagation Experiment at Ka-Band in French Guiana: First Year of Measurements

    摘要: ONERA, the French Aerospace Lab, and CNES, the French Space Agency, are currently running a Ka-band propagation experiment at the Guiana Space Centre (CSG) in Kourou (French Guiana). A rain gauge and a beacon receiver able to record the 20.2 GHz beacon signal of the Amazonas 3 satellite have been deployed. The equipment is operational since January 1, 2017 and the duration of the experiment has been set to 3 years. This letter addresses some results of the first year of measurements (from January 2017 to December 2017). The annual and monthly Complementary Cumulative Distribution Functions of rainfall rate and rain attenuation are presented as well as a comparison with the rain attenuation prediction method recommended in ITU-R P.618-13.

    关键词: Equatorial area,Ka-Band,Satellite communications,Propagation,Measurements

    更新于2025-09-23 15:22:29

  • Design of A Two-Dimensional “T” Shaped Metamaterial with Wideband, Low Loss

    摘要: A novel two-dimensional (2D) metamaterial structure with center symmetric "T" shaped unit is designed, fabricated, and measured in this paper. The proposed metamaterial comprises of a 2 × 2 array of area 4.3 mm × 4.3 mm, etched on single side of FR4 substrate. The simulation and measurement show that the novel metamaterial has a double negative range frequency of 20.16–37.47 GHz with an absolute width of 17.31 GHz, relative width of 60.07%, small unit loss of 0.16 dB, and small size of 0.07 λ0 in 2D. Furthermore, the double negative region of the proposed metamaterial operates through K band and Ka band, it can be widely used in satellite communication and broadband digital transmission.

    关键词: center symmetric "T" shaped,Two dimensions,low loss,wide band

    更新于2025-09-23 15:22:29