Weihua Zhang's research while affiliated with Tianjin University of Technology and other places

... Traditional glucose sensing methodologies primarily rely on enzymatic reactions catalyzed by glucose oxidase or glucose dehydrogenase enzymes immobilized onto electrodes [35,36]. While enzymatic sensors offer high specificity and sensitivity, they are often limited by issues such as enzyme instability, susceptibility to interference, and high production costs [37][38][39]. In response to these pressing challenges, our research focuses on the development of a novel non-enzymatic glucose sensor platform based on polyaniline nanofibers. ...

... Surrounding refractive index (SRI) sensing is of great importance in biological detection [1][2][3], chemical analysis [4], and environment monitoring [5]. Owing to those unique advantages, e.g., anti-electromagnetic interference, light weight, compact size, corrosion resistance, and high sensitivity to the ambient medium, the fiber-based SRI sensors have recently attracted a great interest [6][7][8][9][10][11][12][13][14][15][16][17]. To date, various of the fiber-based SRI sensors have been proposed and demonstrated, which include the long-period fiber grating (LFG)-based one [6], the cascaded fiber Bragg gratings (FBGs) but with droplet-like structure (CFBGD) one [7], the surface plasmon resonance (SPR)-based fiber one [8], the LFG but using the over-coupled resonant mode one [9], the dispersion turning point (DTP) method-based LFGs [10][11][12], the LFG with a reduced diameter one [13], the tapered no-core fiber (TNCF) [14], and the spindle-shaped few-mode fiber (SFF) one [15]. ...

... When the refractive index of the external environment changes, ∆n t eff changes, resulting in a change in ∆ϕ i , which further creates a shift in the interference spectrum. The wavelength shift in the interference spectrum (λ dip ) with the change in the external refractive index (n s ) can be expressed as follows [27]: ...

... The Complementary Cumulative Distribution Function (CCDF), a mathematical technique, is used to evaluate the Peak-to-Average Power Ratio (PAPR). The CCDF determines the probability that an OFDM signal's PAPR will exceed a particular threshold αth [3]. Hence, the OFDM signal's CCDF is in equation (5): ...

... Given the aforementioned advantages, optical fiber sensing technology emerges as an ideal choice for salinity and temperature measurement [10][11][12]. At present, optical fiber sensing techniques for salinity and temperature measurement include fiberoptic SPR [13], multimode interference effect [14], fiber grating [15], micro/nanofiber [16], specialty fiber [17], etc. Of these, optical fiber sensors based on multimode interference have provided significant improvements and hence there have been major contributions in this field [18]. ...

... The large refractive index difference between the no-core tapered fiber and the external surrounding still drives the excitation of modes and the creation of evanescent waves-without the need for ultrashort waist diameters (below 10 µm). A no-core based tapered fiber sensor was also investigated for the detection of glucose [34]. Similar to the operation reported by [33], the no-core fiber was spliced in between two single-mode fibers in order to induce the excitation of modes from the core mismatch and the large refractive index difference between the no-core fiber and the external surrounding. ...

... Wavelength switchable erbium-doped fiber laser (EDFL) is used for laser communication, fiber sensing, spectrum analysis, laser radar, and wavelength division multiplexing (WDM) owing to its advantages of narrow linewidth, wide wavelength tuning range, stable laser output power, high side-mode suppression ratio (SMSR), and long working span [1][2][3][4][5]. In recent years, several methods such as micro-structure Mach-Zehnder interferometer (MZI), Fabry-Perot (FP), Sagnac loop, tunable fiber grating, and non-linear fiber structure have been proposed for the generation of flexible and stable wavelength switchable laser output [6][7][8]. ...

... Henceforth, for sensor 1, the GIMF fiber, when paired with CLF, effectively minimizes coupling loss [20] and dispersion loss [21] by combining most of the higher-order modes that escape due to core mismatch between CLF and the output SMF. The combination of CLF along with FMF in sensor 2 improves the modes stability for the output transmission spectrum, as the fiber supports only a few lower-order modes to transmit through, and compensates for the variation in core diameter between the CLF and the SMF at the output stage, resulting in a significant reduction in coupling loss [22], [23]. ...

... A dual-parameter sensor usually has two channels, which allows for measurements in different locations, or it can have dual-sensing capabilities combined in a single channel, such as: hollow core fiber (HCF) and photonic crystal fiber (PCF) (Yu et al. 2016), D-shaped SMS and fiber Bragg gratting (FBG) (Dong et al. 2019), singlemode-fewmodehollowcore-fewmode-singlemode fiber (SMF-FMF-NCF-FMF-SMF) (Zhao et al. 2021), multimode-singlemode-singlemode fiber (MSM) (Huang et al. 2019), among others. ...

... Several ways to minimise PAPR have been presented [5]. Some of these methods, such partial transmit sequence and chosen mapping, need side information from the receiver [1,19]. MU-PP-GDm [29] reduces PAPR while maintaining transmission quality. ...