A rod antenna with a meander element for hand-held phone

An inverted‐L monopole antenna loaded with a meandered wire for GSM/DCS dual‐band mobile phones

“…This letter proposes a novel low-profile inverted-L wire monopole antenna loaded with a meandered wire for GSM/DCS dual-band mobile phone applications. The total antenna height from mobilephone ground plane is only 14 mm or about 4.2% of the lowest operating wavelength, which is much less than that reported in [1][2][3][4]. The low profile of the proposed antenna has the advantage being less prone to breakage and also makes it very promising for the proposed antenna to be placed within the mobile phone housing where it will not protrude.…”

“…Wire monopole antennas in the form of a straight rod [1], a folded loop [2,3], and a helix or wound coil [4] for applications in mobile phones have been demonstrated. Most of the designs, however, are for single-band operation, which greatly limits their applications in present-day mobile phones, which are usually designed for dualband operation.…”

“…Fiber dispersion along with laser chirp generates composite second order (CSO) in multiple-RF-channel analog lightwave transmission systems. Several compensation methods have been proposed to improve the system's CSO performance, such as the use of dispersion compensation fiber (DCF) within the fiber transmission link [1], or employing differential detection techniques through two-fiber transmission to recombine the RF signals from the optical receiver in-phase [2]. However, poor carrier-to-noise ratio (CNR) performance will be obtained due to the high insertion loss of the DCF for the former.…”

Asymmetric Impedance Vibrator for Multi-Band Communication Systems

“…The development of mobile communication systems requires that mobile phones operate in several frequency ranges, for example, in the GSM 900 (880 ÷ 960 MHz), GSM 1800 (1710 ÷ 1880 MHz) ranges adopted in Europe and Asia, or in GSM 850 and GSM 1900 ranges adopted in North America. In the early stages of cellular communication development, the following external antennas: rectilinear perfectly con-ducting vibrators [4,5], capacitive type impedance monopoles [6], inductive spiral impedance antennas [7,8], cone-shaped antennas [9], and combinations of monopoles and spirals [10][11][12] were mainly used. In all known cases, only antennas with symmetric excitation have been developed.…”

“…Of course, the multi-frequency antenna operation implemented by expanding operating band can cause a significant weakening of its noise-immunity properties. Therefore, designers traditionally resort to combining several antennas operating at different frequencies [10][11][12][13][14][15][16]. This approach complicates the design of an antenna module and is an obstacle to its miniaturization.…”