Search

An octa-band mobile antenna with a wide beamwidth in the endfire direction of the phone for n256-band (1980–2010 MHz and 2170–2200 MHz) satellite communication is proposed. The proposed antenna comprises a low-frequency band (LB) antenna and a middle-/high-frequency band and satellite (MHB&Satellite) antenna. A floating branch working at the 0.5-wavelength mode is proposed to achieve the wide beamwidth in the endfire direction for satellite communication. To cover more cellular bands, two parasitic branches are included in the floating branch to construct the MHB&Satellite antenna. The branches of the LB antenna and MHB&Satellite antenna are shared within a compact size using a low-stop and high-pass filter. The measured results show that the −6-dB impedance bandwidths are 299 MHz (683–982 MHz) and 1088 MHz (1627–2715 MHz). The measured efficiencies are between 44% and 53% for the LB antenna and between 50% and 70% for the MHB&Satellite antenna. At 2.1 GHz, the measured peak gain is 2.44 dBi and the beamwidth with a gain of higher than 0 dBi is 92° ( $\theta =0^{\circ }- 32^{\circ }$ and 300°–360°) in the xoz-plane, and is 196° ( $\theta =0^{\circ }- 110^{\circ }$ and 274°–360°) in the yoz-plane, respectively. The proposed antenna holds the characteristic of the wide beamwidth in the endfire direction in the S-band and the octa-band operation for simultaneous 4G LTE and satellite communication.

In this paper, a polarization encoder with a polarization conversion function is investigated using a layered photonic structure comprising nonlinear materials and indium antimonide. The electric field of the incident linear polarization waves considered are parallel to the x-y plane at an angle of 45° to the x-axis, and can be decomposed into components directed along the x- and y-axes, generating two polarized waves: transverse electric and transverse magnetic waves. Due to the nonlinear effect and the temperature and magnetic flux density tunable properties of indium antimonide, the light intensity, temperature, and magnetic flux density can be used to adjust the reflection phase difference and polarization form. Discussing the influences of these three physical quantities on the phase difference, the incident linear polarization wave and reflected circular polarization wave conversion, the circular polarization conversion of two different rotations and the circular polarization separation of a certain bandwidth can be simultaneously realized with the specific modification of the light intensity or temperature. Moreover, four disparate input logic levels composed of temperature and magnetic flux density achieve specific encoding outputs for all polarization forms. This signifies that polarization selection through control of the logic codes can be easily attained. The consequences show that this form of polarization conversion and encoding is tailored and can be accurately manipulated. Hence, this provides a novel foundation for tunable and diverse polarization splitters and selectors.