novel wideband antenna with five reconfigurable polarization states is presented for intelligent IoT applications, where polarization agility can be exploited by a higher-layer controller to enhance link reliability in dynamic multipath environments. To achieve wideband performance across all polarization states, coupling mechanisms are strategically introduced into the radiation structure, feeding structure, and feeding network simultaneously. Firstly, through equivalent circuit analysis, shorting pins, metal strips, and slots are integrated into the radiation structure. The coupling mechanisms excite first- and second-order frequency responses, resulting in significant gain improvement and overlapping bandwidth enhancement. Secondly, a co-planar capacitive feeding structure is implemented into the feeding network to improve impedance matching. Subsequently, weakly coupled transmission lines are deployed within both differential and full-polarization feeding networks. Such a configuration ensures wide overlapping bandwidth performance throughout all five polarization states by suppressing phase shift errors. Finally, by controlling the ON/OFF states of PIN diodes, the feeding network generates desired phase differences, enabling the proposed antenna to be reconfigured between five polarization states, i.e., linearly polarization (LP) with three orientations, left-hand circularly polarization (LHCP), and right-hand circularly polarization (RHCP). Experimental results demonstrate that the antenna achieves an operating bandwidth of 8–13 GHz (47.6%), with axial ratio (AR) < 3.0 dB and in-band gain fluctuation < 3.0 dB. Characterized by wide bandwidth, full-polarization agility, and standard fabrication, the design presents a viable solution for demanding multi-polarization applications in industrial Internet of Things (IoT) scenarios.

In this article, a quasi-isotropic antenna with system ground plane is proposed for Internet of Things (IoT)-based smart home applications. The proposed antenna consists of a system ground plane and a modified$\lambda $/4 U-shaped radiator with vertical branch passing through the ground plane but not contacting it. The antenna operates in balanced mode and does not excite the system ground plane mode (i.e., similar to the chassis mode in the terminal antenna), which is essential to obtain quasi-isotropic radiation pattern. The dimensions of the designed antenna are$0.13\,\,\lambda \times 0.14\,\,\lambda \times 0.12\,\,\lambda $, which does not take into account the size of the system ground plane. The detailed analysis and evolution process of the designed quasi-isotropic antenna are presented. In particular, the principle that a modified$\lambda $/4 U-shaped radiator without a system ground plane can produce a quasi-isotropic radiation pattern is first stated; then the principle that the modified$\lambda $/4 U-shaped radiator can produce a quasi-isotropic radiation pattern when the system ground plane is present is stated, and at the same time, the method for impedance matching and bandwidth improvement of the antenna is explained; and finally, a parametric analysis is performed to determine the influence of important antenna structure parameters on antenna performance. To demonstrate the performance of the proposed antenna, the antenna prototype was fabricated and measured. The simulated (measured) bandwidth (BW), gain variation (GV), realized gain, and efficiency at 2.45 GHz are 110 MHz (120 MHz), 6.3 dB (7.7 dB), 1.6 dBi (1.36 dBi), and 98% (82%), respectively. Compared with the state-of-the-art quasi-isotropic antennas, the proposed antenna can still generate a quasi-isotropic radiation pattern with a small GV in the presence of a system ground plane, making it more suitable for practical engineering application scenarios, which is a promising antenna candidate for routers in IoT-based smart homes.

Elastic cognitive optical network(ECON) embeds artificial intelligence technology into network management to enable resource self-optimization ability, which has aroused the wide interest of researchers. However, realizing precise traffic prediction (TP) in optical networks has been a challenging problem due to channels’ complex variable bandwidth conditions. We provide an ECON architecture and propose a graph-convolutional-network-transformer (GCN-transformer) TP algorithm. The proposed algorithm has been evaluated and compared with the traditional schemes. We build a testbed for the proposed algorithm by OMNET++. The results show a prediction accuracy of 99.74%, which reduces the inaccuracy by 2.03% compared with other typical algorithms.

The resolution of the microwave radar coincidence imaging (MRCI) can break the diffraction limit, which has been validated by experiments. However, there is still no theoretical analysis. In this article, the resolution of the MRCI is theoretically analyzed using the orthogonal subspace projection algorithm based on the space spanned by the discrete reference radiation mode. First, a target location estimate (TLE) method using the data from the nonfocusing radar array of the MRCI system is proposed to estimate the target position assisted by the equivalent detection method. The estimation precision of the TLE method is approximately equal to the 3-dB beamwidth of the coherent transmitting radar array with the same aperture; hence, the imaging plane can be obtained. Then, the equivalent internal noise (generated by the error of the target distance estimation, i.e., the location of the imaging plane) is theoretically analyzed. Finally, the imaging resolution threshold of the MRCI system is theoretically analyzed. The relationship between the resolution threshold and the factors (such as the deployment of the transmitting radar array, the distance between the target and the radar array, and the signal-to-noise ratio of the imaging system) is summarized. The proposed estimation method and the analyses of the MRCI system are validated through a set of simulations and experiments.

A super-resolution computational imaging method, called post random modulation radar imaging, based on single-input multiple-output radar detection system is proposed in this letter. In the proposed method, the target is detected in coherent mode using the multilinear frequency modulation signal. The echoes received by the radar elements of the receiving array are recorded, respectively. Then, random modulations of the directional pattern factor of the receiving radar array, which are nonlinear processes, are optimized according to the position and the size of the target that are estimated roughly using the traditional method. Finally, the super-resolution radar imaging is obtained to solve the equation group formed by the data from the nonlinear post random modulation process. The resolution of the proposed imaging method can break the diffraction limit corresponding to the aperture of the receiving radar array. The anti-interference ability of the proposed approach is improved significantly compared with the incoherent imaging method using a multiple-input single-output structure. Experiments are carried out to validate the proposed approach.

How to implement software agent is a key problem for developing agent-oriented programming languages and tools. Aiming to solve this problem based on the OO technology, this paper first discusses differences between agent and object, and then puts forward an implemental architecture of software agent based on the OO technology and a simplified improvement of the BDI agent model. An OO-based design framework of software agent is also proposed by using the POAD method finally. These research results are helpful to clarify how to suitably extend the OO method for solving the key problem

A distributed simulation environment of fluid flow as a study case is firstly brought forward and then a simulation-based universal distributed solving process that is universal in many problem domains is put forward. Based on the process, the agent-oriented early requirement analysis of the study case has been carried out basically, and the feasibility and rationality of agent-oriented method and difficulty of object-oriented method for modeling complicated intentional feature have also been discussed.