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A wideband internal antenna that is composed of a coupled feeding part and four branch lines is presented. The proposed antenna can operate within two wide bands of 0.64-0.99 GHz and 1.65-2.85 GHz which cover 11 service bands including LTE 700/2300/2500, AMPS800, GSM900, DCS1800, PCS, UMTS, WiBro2350, ISM/ Bluetooth, and WLAN for the 4G mobile phone. The antenna could be available not only for future 4G service but also for current 2G/3G services. This internal antenna is fabricated within the limits of a 65 Â 11 Â 7 mm 3 volume and suitable for smart phones or personal digital assistant (PDA) applications. The measured results are in agreement with the simulation. V C 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:513-516, 2013; View this article online at wileyonlinelibrary.com.ABSTRACT: A new vertically polarized omnidirectional antenna, inspired by an old design, has been studied, optimized, realized, and measured. With a radiation pattern similar to the classical monopole on a ground plane, the proposed antenna concept provides a much larger bandwidth and a very low profile. This antenna has numerous potential applications for mobile communications, UWB, and others.

A simple printed ultrawideband (UWB) antenna with reconfigurable band‐rejected characteristics is proposed. The antenna was fabricated on an FR‐4 epoxy substrate and has a volume of 40.0 × 32.0 × 1.0 mm3. The simulated and measured results show that the antenna has nearly omnidirectional patterns, stable gain, and an available impedance bandwidth of 9.38 GHz which covers 2.34–11.72 GHz. By etching two slots in the radiator, band‐ notched features centered at 3.5 and 5.5GHz are achieved. With adding two microelectromechanical system switches across slots, the band‐rejected characteristics can be reconfigurable and the proposed antenna is capable of operating among none or single or dual band‐notched modes. Meanwhile, to discuss the mechanisms of the band‐rejected properties, the conceptual equivalent circuit models are presented. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2401–2405, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27061

In this paper, a novel direction of arrival (DOA) estimation algorithm called the Toeplitz fourth order cumulants multiple signal classification method (TFOC-MUSIC) algorithm is proposed through combining a fast MUSIC-like algorithm termed the modified fourth order cumulants MUSIC (MFOC-MUSIC) algorithm and Toeplitz approximation. In the proposed algorithm, the redundant information in the cumulants is removed. Besides, the computational complexity is reduced due to the decreased dimension of the fourth-order cumulants matrix, which is equal to the number of the virtual array elements. That is, the effective array aperture of a physical array remains unchanged. However, due to finite sampling snapshots, there exists an estimation error of the reduced-rank FOC matrix and thus the capacity of DOA estimation degrades. In order to improve the estimation performance, Toeplitz approximation is introduced to recover the Toeplitz structure of the reduced-dimension FOC matrix just like the ideal one which has the Toeplitz structure possessing optimal estimated results. The theoretical formulas of the proposed algorithm are derived, and the simulations results are presented. From the simulations, in comparison with the MFOC-MUSIC algorithm, it is concluded that the TFOC-MUSIC algorithm yields an excellent performance in both spatially-white noise and in spatially-color noise environments.