We propose an uplink full-duplex (FD) cooperative non-orthogonal multiple access (NOMA) system, where a dedicated Full-duplex (FD) relay is used to help two uplink users transmitting information to the base station. A novel FD relay transmission mode is proposed, in which the FD relay utilizes successive interference cancellation (SIC) and self-interference cancellation to decode two users symbols at the relay receiving antenna, and the relay transmitting antenna transmits superimposed signal to the base station using superposition coding. In this paper, we also consider a more realistic scenario where selfinterference cancellation is imperfect. Hence, the residual-self interference exists. Moreover, the ergodic sum rate and the outage probability of the proposed system are investigated and the accurate analytical expressions are derived. Simulation results validate that, compared with the uplink half-duplex (HD) cooperative NOMA system and the uplink HD cooperative orthogonal multiple access (OMA) system, our proposed system obtains better performance of the ergodic sum rate and outage probability in the main signal to noise ratio (SNR) regime.

Non-orthogonal multiple access (NOMA) is widely studied in both academia and industry due to its high spectral efficiency over orthogonal multiple access (OMA). To effectively improve spectrum efficiency, an amplify-and-forward (AF) cooperative NOMA system is proposed as well as a novel detection scheme is proposed, in which we first perform successive interference cancellation (SIC) twice at U1 for the two signals received from two time slots to remove interference from symbol 2, then two new signals apply max ratio combining (MRC). In addition, a closed-form upper bound approximation for the ergodic capacity of our proposed system is derived. Monte-Carlo simulations and numerical analysis illustrate that our proposed system has better ergodic capacity performance than the conventional cooperative NOMA system with decode-forward (DF) relay, the conventional cooperative NOMA system with AF relay and the proposed AF cooperative NOMA system in [16]. In addition, we can see that ergodic capacity of all NOMA cooperative systems increase with the increase of transmit SNR. Finally, simulations display that power allocation coefficients have little effect on ergodic capacity of all NOMA cooperative systems. This is due to this fact that ergodic capacity of two symbols can be complementary with changing of power allocation coefficients.

Dendrobium officinale is an important medicinal material in traditional Chinese medicine. Due to the superior quality and high market value of the Huoshan Dendrobium officinale, products from other regions are frequently sold as counterfeit Huoshan varieties. To investigate the authenticity identification of Huoshan Dendrobium officinale, this study utilized a hyperspectral imaging system covering the wavelength range of 900–1700 nm to collect hyperspectral images from Huoshan and other major production regions. After extracting spectral data of samples, spectral preprocessing was performed using Savitzky–Golay (SG) smoothing and first derivative (FD) transformation. By analyzing Principal Component Analysis (PCA) loading coefficients, up to 20 key wavelengths were selected, and a discriminant model was established based on the XGBoost algorithm. Model analysis revealed that when using the top 13 key wavelengths selected by PCA, the test accuracy for identifying Huoshan Dendrobium officinale reached 87.5%, effectively verifying its authenticity. This study contributes to promoting the healthy development of the market for traditional Chinese medicinal materials such as Dendrobium officinale.

In order to effectively solve the problem of spectrum shortage, cognitive radio (CR) and full-duplex (FD) have been proposed and widely studied in recent year. In this paper, we integrate CR and FD techniques, consider a FD spectrum sharing CR networks, where both secondary users (SU1 and SU2) are equipped with dual antennas, one of which is used to receive signals, and the other is used to transmit signals at the same time and frequency. Under peak interference power and peak transmit power constraints, we analysis the ergodic sum capacity and the outage probability based on the FD spectrum sharing CR networks and the conventional spectrum sharing CR networks. Furthermore, under no peak transmit power constrain and perfect self-interference cancellation (SIC), based on the FD spectrum sharing CR networks and the conventional spectrum sharing CR networks, the closed-form expressions of the theoretical upper bound of the ergodic sum capacity and the outage probability are derived by two lemmas and four propositions. Accurate mathematical analysis display, under the same bandwidth, the upper bound of the full-duplex spectrum sharing CR networks ergodic sum capacity is twice as much as the traditional spectrum sharing CR networks, and the FD spectrum sharing CR networks based on SU1, also has better upper bound performance on the outage probability than the traditional spectrum sharing CR networks. Simulations results validate that, the FD spectrum sharing CR networks obtains better communication performance than the conventional spectrum sharing CR networks, especially when the residual self-interference is small. Finally, we also can see that the simulation upper bound is completely consistent with the theoretical analysis upper bound, whether in the FD spectrum sharing CR networks or the conventional spectrum sharing CR networks. So also verifies the correctness of the theoretical upper bound derivation.