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Because of intermittence and fluctuation of photovoltaic (PV) power, it is difficult to enhance prediction accuracy. To sustain high-efficient operation of power system, this paper proposes a hybrid method to predict the short-term PV power. It consists of components separation of PV power, parameters optimization and re-construction of prediction result. Firstly, the methods based on the identifying of feature frequency and mutual information maximum are proposed to optimize the mode number and penalty factor of VMD, respectively. The optimized VMD (OVMD) is used to decompose the complicated fluctuation components of PV power into single component. Then, the improved PSO (IPSO) based on non-linear inertia weight of anti-sine function is proposed to optimize the number of hidden layer nodes, learning rate and iteration number of LSTM network. The optimized LSTM is used to predict each single component of OVMD decomposition. Thirdly, the prediction result of each single component is re-constructed to obtain the final PV prediction power. The experiment result indicates that the prediction accuracy of the proposed method (OVMD-IPSO-LSTM) outperformances the other typical methods. By the improvement of the traditional method (VMD and PSO) and the parameter optimization of LSTM, this hybrid method makes a contribution to the prediction of short-term PV power.

Array element rotation could serve as the fifth dimension that can be modulated to synthesize desired array patterns except for the excitation amplitude, phase, element position, and time sequence. A method of synthesizing shaped patterns for linear, planar, and cylindrical conformal arrays by optimizing element rotations and excitation phases considering mutual coupling (MC) is presented. The rotation of an element in its local coordinate system (LCS) is approximately described by rotating its vectorial active element pattern (VAEP). Then, the rotated patterns are transformed to the global coordinate system (GCS) by coordinate transformation and scattered interpolation to calculate the array pattern. In the end, a refined strategy is adopted to reduce the error introduced in the rotated VAEP approximation. Numerical examples and measurements are presented to validate the effectiveness of the proposed method.

In this paper, patch antenna structures are studied to simultaneously excite the ground radiation mode and patch radiation mode. Based on the analysis of characteristic current distribution on the ground plane of patch antenna, an exciting method of the ground radiation mode is proposed. Then a dual-mode patch antenna of patch radiation and ground radiation is designed, which can achieve a wideband radiation using two modes resonating at two adjacent frequencies. To improve the radiation efficiency of the ground mode, the electric field distribution of the dual-mode antenna is investigated in detail and the electric field models for two modes are constructed. It is suggested that the additional notches introduced on the ground plane can enhance the resonance component of the ground mode. By this way, the modified patch antenna presents better radiation efficiency over the operating band. The measurement results show that the relative bandwidth of the patch antenna prototype with the notches is about 16.2%, defined by the reflection coefficient less than -10 dB. The proposed dual-mode antennas have the inherent characteristics of weak directivity, for that the antenna application scenarios also are indicated.

Integrated space and terrestrial networks are expected to be a key technology for beyond 5G communications systems. One main challenge posed for the antennas is the array performance deterioration caused by orientation changes of various elements mounted to conformal platforms. To overcome this challenge, a reconfigurable antenna element that can switch among four linear polarizations is reported and applied to a conformal array. An efficient array synthesis algorithm is utilized to attain high-gain, low-sidelobes, and low-cross-polarization characteristics. A linear conformal array is presented to verify the effectiveness of the developed algorithm.

High efficiency conformal transmitarrays using very thin dual-layer elements are very rare in open literature as there is always a tradeoff between the array thickness and the efficiency. This paper addresses this problem by developing a new ultra-thin Huygens element which consists of two metal layers with only 0.5 mm thickness (λ 0 /60 at 10 GHz). The design procedure for specific phase values of the element is developed, and eight elements are designed to cover a quantized 360° phase range with a maximal 1.67 dB loss. This element is applied to a conformal transmitarray, realizing a measured peak gain of 20.6 dBi and a 47.4% antenna efficiency, which is much higher than other conformal transmitarrays.

Fast-speed, mast-capacity, and low-cost communications are highly desired for future wireless systems. Single-feed overmoded slot-based rectangular cavity antennas are developed to meet this demand. A TE (10)(11)(0) mode is excited in the cavity with a rectangular waveguide. A total of 110 slots appropriately etched in its top surface yields a system that radiates its beam into the broadside direction with a gain of 26.6 dBi. An engineered phased patch surface is then introduced to facilitate tilted-beam pattern for high-order-mode cavity antennas. The realized cavity antenna augmented with an appropriately-shaped phased patch surface attained a tilted beam at 30° with respect to the broadside direction. An antenna prototype was fabricated, and measured results agree well with the simulated ones.

An iterative spatiotemporal Fourier transform (STFT) method is proposed to synthesize a wideband scannable frequency-invariant (FI) pattern for a uniformly spaced linear antenna array. This method applies a modification-and-projection iteration to continuously update the synthesis results. An example for synthesizing a scannable FI pattern with uniform sidelobe level (SLL) is provided to verify the effectiveness and efficiency of the proposed method.

This paper achieves the circular flat-top beam pattern synthesis of a uniform amplitude sparse planar dipole array by joint optimization of element rotations, positions and phases. Moreover, the minimum element spacing constraint for the synthesized array is considered by using an asymmetry mapping method (AMM). Importantly, on the basis of obtaining an equivalent or better pattern performance, the synthesized array can save 33.06% elements and avoid the usage of unequal power dividers than published results.

© 2019 IEEE. A new method incorporating the least-squares active element pattern expansion (LS-AEPE) into the iterative Fourier transform (IFT) procedure is introduced to synthesize the shaped beam pattern for the linear array with the strong scattering environment. The synthesized result, involving the mutual coupling and platform effect, is more accurate than traditional IFT, and the procedure takes very litter time. A 16-element array surrounded with many irregular scatters is given to validate the accuracy and efficiency of the introduced method.

It is shown in this work that the FI pattern synthesis can be treated as an optimization problem for minimizing the mainlobe frequency variation. To control both the mainlobe and sidelobe regions, we introduce several constraints imposed on the broadband pattern, called the look-direction constraint, the spatial response variation constraint and the sidelobe constraint, respectively. The whole optimization process needs to perform the SOCP solver. A synthesis of FI pattern with low sidelobe level (SLL) is given to validate the accuracy and effectiveness of the proposed method.

Synthesis of sparse arrays with reduced number of elements are significant for some applications where the available space, weight and the cost of the antenna system is very limited. In recent years, a variety of advanced techniques have been presented to deal with sparse array synthesis problems in either narrow and wideband cases. This paper presents a brief review of these techniques, and gives rough comparative study on some of sparse array synthesis methods.

A substrate integrated waveguide (SIW) slot antenna array with low sidelobe level (SLL) and high gain is presented. The antenna consists of a 1x6 power divider and 6 8-element radiating slots in a single-layer SIW structure. Simulated S 11 is less than −10 dB over the frequency band of 24-24.5 GHz and simulated gain is about 21.07 dB at 24.25 GHz. The achieved SLL is −20.94 dB.

In this paper, the stability of switched linear systems under dual-terminal data injection cyber attacks is studied. The proposed event-triggering strategy can only sample and update the system state when a defined error exceeds a given threshold. Dual-terminal injection attacks and attack delays are considered. Then, the corresponding closed-loop system is derived. By utilizing Lyapunov functional method and average dwell time technique, stability conditions for the closed-loop system under the event-triggering strategy and dual-terminal injection attacks are given. Accordingly, the design conditions of state-feedback controllers are presented. Finally, simulations are provided to verify the validity.

© 2019 IEEE. This paper presents a modified Fourier transform method to synthesize a broadband array with frequency-invariant (FI) mainlobe and multiple space-frequency nulls. In this method, a iterative Fourier transform is used to design multiple optimized reference patterns which have the same mainlobe shape but with different sidelobe or null distributions. These reference patterns are used for describing different radiation requirements in different sub-bands of the whole frequency band. Then, a desired broadband spatial spectral distribution can be obtained by matching it to each reference pattern at each sub-band, and a broadband excitation distribution for generating the desired FI pattern can be efficiently found by performing an inverse fast Fourier transform (IFFT) on the broadband spatial spectral distribution. An example for synthesizing a FI beam pattern with two space-frequency nulls is provided to verify the effectiveness and efficiency of the proposed method.

© 2019 IEEE. In this work, a formula is derived for generating optimally directive pattern for an arbitrary antenna array including mutual coupling effect, and it is then applied to design the optimally directive four-element end-fire dipole array. Synthesis results show that the obtained directivity coefficient is about 2dB and 3.5dB higher than those of ordinary and hansen-woodyard four-element end-fire dipole arrays.

This paper concerns the dissipative control for networked switched linear systems subject to event-triggering strategies and quantization. Multiple event-triggering strategies are adopted to determine whether the sampled data to be transmitted. In order to make full use of network bandwidth, logarithmic quantizers are applied in the networked switched systems. In detail, by using a delay system analysis approach, a time-delay closed-loop switched system is developed. Then, sufficient conditions are obtained to guarantee the dissipative control performance of switched system by utilizing piecewise Lyapunov functional method and average dwell time technique. Furthermore, by designing event-triggered dissipative controllers and event-triggering strategies' parameters, sufficient conditions for the stability of the closed-loop system are provided and the system is dissipative. Finally, numerical simulation results show the effectiveness of the proposed method.

In order to break through the current situation of final vehicle logistics industry's meager profit, we proposed a new service mode for final vehicle assembly and logistics. In the mode, a composite Assembly Distribution Center (ADC) was set up, which achieved the parts transportation and terminal distribution of final assembly vehicle and solved the problem of high damage rate and high cost caused by the long haul final vehicle transportation. Taking AnJi automobile logistics as an example, the internal layout of the ADC in Tianjin was designed. It included the location of the production line, the specifications of the storage area and the range of the sorting area. Using goal chasing method, the production sequence of mixed-model assembly line in ADC was determined. The solving process showed that the time performance is better than other methods’. The group technical theory defined the layout of the parts inventory. The logistics system modeling and simulation of mixed model assembly line were performed with Flexsim. It showed the process from the parts arrival, the first sorting of the parts and the forklift shelf storage, to the second sorting and on-line production. It was only an illustration of the whole operation in ADC without simulation experiment. The paper put forward a new mode to solve the problem of final vehicle logistics in China, and formulated the sequence and layout simulation of the mixed-model assembly line of the core node ADC in the mode.

© 2018 ACES. In this paper, a highly efficient approach is proposed to synthesize the low sidelobe pattern of uniformly spaced circular array. The proposed approach can be generalized to deal with the pattern synthesis for the circular array with directional elements. Numerical examples are given to verify the effectiveness and advantage of this approach.

A new shaped pattern synthesis method is presented in which element rotations, positions and phases are co-optimized to produce a shaped beam pattern for a sparse dipole array. Compared with conventional shaped pattern synthesis using excitation amplitude and phase optimization, the proposed method can not only reduce the number of elements But also avoid the usage of unequal power dividers. A synthesis example is provided to verify the performance of the proposed method.

© 2018 IEEE. A compact bandpass filter (BPF) using two ring resonators and two open stubs is proposed, where fifth-order passband with twelve transmission zeros at the stopband is realized. For demonstration, a filter example with center frequency of 2.04 GHz and 3 dB fractional bandwidth of 18.6% is designed. Good performance including high selectivity in the passband and sharp stopband rejection for the filter has been realized.

This paper introduces a practical single-mode quasi constant-frequency controller that provides practically minimum output voltage deviation during load transients. This control scheme eliminates the need for two separate controllers for steady-state and transient operation and the associated potential mode transition problems which are characteristic of numerous fast response solutions. The controller only relies on the detection of changes in the output capacitor current polarity and a simple PI compensator to provide fast transient response and tight voltage regulation. The effectiveness of this mixed-signal controller is demonstrated with a 600 kHz, 15 W single-phase buck converter based experimental prototype. During load transients, the inductor current is shown to be corrected within one switching cycle with near-minimum output voltage deviation.

© 2018 IEEE. A fourth-order bandpass filter using dual-mode ring resonator and parallel-coupled lines loaded with half-wavelength open stubs is presented in this paper. Six transmission zeros (TZs) and four transmission poles (TPs) from 0 to 2f0(f0 denotes center frequency of the filter passband) can be achieved with the help of two open stubs and open coupled lines, where two TZs are generated by the loaded two open stubs. Finally, a verified physical layout of the proposed filter is designed and simulated with good frequency selectivity, whose ADS and HFSS simulations are in good agreement.

© 2017 IEEE. In this paper, a novel dual-frequency substrate integrated waveguide (SIW) cavity-backed slot antenna using two high-order modes is presented. Determined by the locations and types of the feeding and radiator, the high-order hybrid mode (superposition of TM310 and TM130) and another higher-order mode TM320 in SIW cavity are excited by an inductive window for dual-band application in K-band. The simulated results of the proposed antenna show that the 10-dB impedance bandwidths at resonant frequencies of 21.2 and 26.1 GHz are 400 MHz and 800 MHz, and the realized gains at boresight direction are around 10.7 and 11.9 dBi, respectively. Including its high gain, the designed dual-frequency antenna has the advantages of high front-to-back ratio and low cross polarization level.

In this paper, numerical pattern synthesis (NPS) algorithm integrated with seeded region growing (SRG) method is proposed to synthesize the array in the presence of mutual coupling. In order to obtain the mutual coupling between the array elements, active pattern technique is used to find active element patterns. A 4 × 8 microstrip antenna array is employed to validate the effectiveness of the proposed algorithm including mutual coupling.

This paper studies the guaranteed cost state-feedback control for uncertain switched linear systems with an event-triggering strategy. With the proposed event-triggering strategy, the system state can be sampled and updated only when a defined error exceeds a given threshold, which is very different from the traditional periodic sampling. More specifically, first, sufficient conditions for the stability and guaranteed cost performance of the resulting event-triggered switched closed-loop system are derived by utilizing the average dwell time method and linear matrix inequalities (LMIs) technique. A certain upper bound of the guaranteed cost against the system uncertainties is obtained. Subsequently, another set of sufficient conditions are presented for solving the event-triggered guaranteed cost state-feedback controllers. Furthermore, the Zeno behavior is discussed by presenting a positive lower bound estimation on the inter-execution intervals. Finally, numerical simulations are provided to demonstrate the effectiveness of the proposed approach.

Selecting appropriate element orientations can significantly reduce the sidelobe level of the antenna array. In this paper, a binary coded genetic algorithm (BCGA) which selects the element orientations from specified discrete angles, is proposed to reduce the sidelobe level (SLL) of the array. Compared to the conventional GA, the BCGA is much faster in this application. Synthesis results show the effectiveness and efficiency of the proposed method.

Traditional manual pressure test requires a lot of testers and clients and has difficulty in reproducing errors. Automatic test methods are also used in the test and simulation of trunking system. However, the protocol of trunking system is stateful, some testing methods like packet playback are not suitable for the test of trunking system. This paper presents a design of Domain Specific Language based test platform for broadband trunking system, which embeds a well-designed and easy-writing test script which describes the highly parallel testing scenarios, a controller which dispatches test tasks and several simulators which ensure the test cases can be executed with low latency. With the help of the test script, testers can write test cases easily without knowing much details about the concurrency. The controller interprets the test script, generates test tasks which are then sent to the simulators, gathers result from simulators to makes the test report. With the event-driven asynchronous task engine, high concurrent test cases can be executed in an efficient way.

A shaped power pattern synthesis with reduction of dynamic range ratio (DRR) is presented in this paper. Controlling the DRR of the excitations for the shaped power pattern synthesis is very useful since it can reduce the output power loss and also simplifies the complexity of the feeding network design. The synthesis of shaped pattern is typically a nonconvex optimization problem. To solve this problem efficiently, we formulate the synthesis as Semi-definite relaxation (SDR) form which allows to relax some non-convex constraints so as to formulate the problem into a convex form. Then it can be efficiently solved using readily available toolbox. Finally, numerical example is presented to show the effectiveness and advantages of the proposed method.

A novel high-selectivity triple-mode microstrip bandpass filter (BPF) using short- and open-stub loaded spiral resonator is presented. Because of the spiral structure, the size of designed BPF is reduced greatly. Then the odd- and even-mode method is used to analyze resonant frequencies of the resonator. Based on the analysis, a prototype of the proposed BPF with good selectivity is designed whose center frequency is at 4.3 GHz. Finally, the measured results are shown, which are in good agreement with simulations.

A new tri-mode banpass filter (BPF) using a half-wavelength spiral resonator center-loaded with two T-shaped open stubs has been presented. Analyzed by the odd- and even-mode method, an odd mode and two even modes of the proposed tri-mode resonator could be flexibly controlled by tuning the electrical length of the spiral resonators and T-shaped stubs. For demonstration purpose, a tri-mode filter example with passband centered at 1.8 GHz has been implemented.

In this paper, we propose a new method to design a beam-scanning sparse array with minimum spacing constraint. The proposed method consists of two optimization steps. In the first step, an iterative reweighted L1-norm optimization is used to obtain an initial sparse array without minimum spacing constraint. In the second step, we carry on a series of element combination and perturbations to meet the minimum spacing constraint. An example is given to design a sparse array which has the minimum spacing of 0.5 wavelength and the beam scanning from −45° to 135°.