Smart antennas have received increasing interest for mitigating interference in the multiple-input-multiple-output (MIMO) wireless local area network (WLAN). In this paper, a dual-band dual-polarized compact bowtie dipole antenna array is proposed to support anti-interference MIMO WLAN applications. In the antenna array, there are 12 antennas, six for horizontal polarization and six for vertical polarization. In order to achieve dual linear polarizations and beam switching, six horizontal antennas are placed in a sequential, rotating arrangement on a horizontal substrate panel with an equal inclination angle of 60 to form a symmetrical structure, while the other six antennas for vertical polarization are inserted through slots made on the horizontal substrate panel. Furthermore, six pairs of meandered slits are introduced to reduce the mutual coupling between horizontal antennas in the lower band. A prototype of the array with a dimension of 150 150 60 mm is manufactured and exhibits the characteristics of high isolation, good front-to-back ratio, and average gains of 4.5 and 5 dBi over the 2.4-and 5-GHz band, respectively. The MIMO performance of the array is analyzed and evaluated by mutual coupling, the total active reflection coefficient (TARC) and the envelope correlation coefficient. The anti-interference capability of the array is also investigated by the experiment.

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In order to overcome the limitations of single application of ice storage cold and water source heat pump technology, the organic combination of the two can “peak load shifting” and save the cost of system operating. It is important to know how to reasonably distribute the load, which makes the system run with minimum cost. By comparing the operating costs of several control strategies for ice storage system of water source heat pump in a CBD, the advantages of control strategies for dynamic load distribution is outstanding by comparing with the priority control strategies of chiller or ice storage.

In this paper, an improved complex image method to derive closed form periodic Green’s function for problem of scattering from perfectly conducting periodic surfaces is considered. The complex image technique represents a close-form periodic Green’s function consisting of a finite series of real sources and two finite series of complex sources with complex locations and amplitudes. Then the integral equation with the complex images periodic Green’s function in the kernel is solved by the method of moments. Results and computational times obtained by this improved complex image method and the previous one are compared with those obtained by the spectral Kummer-Poisson’s method. Results show that the improved complex image method is more accurately than the previous one.

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