Wireless communication is a fundamental requirement because of its low cost, high flexibility and convenience, continuing improvements in speed and connectivity, and accessibility in remote areas. One example is very small aperture terminal (VSAT) communication. A VSAT is a two-way satellite ground station operating at C-band and Ku-band frequencies, with linear and circular polarization in the C band and linear polarization in the Ku band. For the data transmitted by a satellite to be utilized by a user, the antenna on the user side must have dual-wideband and dual-polarization characteristics. In this study, a dual-polarization planar dual-wideband antenna with dimensions of 30 x 39 x 1.52 mm3 was designed using a dual-port approach. The introduction of a slot and perturbation on the patch side results in the dual-wideband characteristics of the antenna. The introduction of slots into the antenna ground results in circular polarization. The proposed antenna has resonant frequencies of 3 - 15 GHz on port 1 and 3.31 – 7.79 GHz and 9.05 – 15 GHz on port 2, with circular polarization characteristics on port 1 and linear polarization characteristics on port 2. On port 1, the gains at frequencies of 4.2 GHz is 3.93 dB, while on port 2, the gains at frequencies of 3.9 GHz is 0.51 dB.

The performance of free-space optical (FSO) communications that using an optical amplifier (OA) in the scheme of an amplify-received (AR)-relaying has a major drawback in the detection of input signal quality under the effects of turbulence. As an OA is based on a fiber-detection (FD) method to receive and delivers a signal at the amplification process stage, there is an opportunity to implement an optical spatial filter (OSF) to improve the quality of an input signal. In this paper, as the continuation of previous work on the direct-detection, the OSF is applied on the AR-relaying. The novelty proposed in this work is the improvement of FD method where the OSF is designed as the integration of cone reflector, pinhole and multi-mode fiber with an OA. The OSF produces an optical signal, the input of the OA, which minimizes the effects of turbulence, background noise and signal fluctuation. Thus, OA in AR-relaying produces signal output with high power and rise up below threshold level. Additionally, an OSF with a lower pinhole diameter produces the best quality of the signal spectral to be delivered into an EDFA. Through this implementation, the performance of optical relaying on FSO can be significantly improved.