Monitoring the functionality of large networks is a difficult problem more and more encountered lately due to the expansion of existing networks and the development of applications that require large networks of sensors, detection systems and telecommunications networks. The main objective of this paper is to automatically monitor a network which comprises of a high number of sensors (e.g. 124) deployed on a large surface (more than 20 sq. km). The collected data is used to model physical phenomena in the atmosphere, thus the quality of data is important and is affected by the incorrect functionality of the equipment. The proposed solution is beyond the original scientific purpose of the network and can be successfully applied in other applications or other network configurations.

This article presents a technique for transforming the polarization of a pyramidal horn antenna by adding multiple layers of frequency-selective surfaces in front of the aperture, in order to rotate the direction of the electric field. Thus, two orthogonal components with the same magnitude, phase-shifted by 90°, are generated. Each frequency-selective surface consists of skewed λ/2 dipoles. Compared to other similar structures, our antenna system combines the field radiated from the horn aperture with the field scattered by parallel frequency-selective surface structures spaced on the same principle as that for designing a Yagi-Uda antenna array. The proposed horn antenna with multiple frequency-selective surfaces can be used as a feed element for a parabolic reflector antenna for maritime satellite communication systems in the X-band or in the lower part of the Ku band, or as part of a sensor for finding the direction of arrival of a wave, in order to orientate an antenna system. The concept was successfully validated on the basis of simulation and measurements. The proposed technique provides a close to unit axial ratio together with a 3 dB increase in gain compared to the conventional horn antenna, at low manufacturing costs.

In this paper are presented the design and the simulation of a broadband pyramidal horn antenna for satellite applications. The design was performed using the method of approximation and the final simulations were performed with HFSS. The proposed antenna operates in the frequency range 12-18 GHz (Ku band). A linearly polarized rectangular guide is used for feeding. The results of the simulations exhibit low voltage standing wave ratio and good radiation properties for the Ku band.

In this paper we present the design, simulation and measurement of a pyramidal horn antenna with linear polarization, operating in the Ku band at 13.3 GHz. The horn antenna is made of aluminium, weighs about 0.7 kg, the cutting of each face of the antenna was done with the help of a computer numerical control and then followed the assembly of each face of the antenna. The simulations performed with ANSYS HFSS show a maximum gain of 21.5 dB, which is in good agreement with the measured results. The pyramidal horn antenna proposed can be a very good candidate for telecommunication applications, atmospheric characterization, as the case of our project.

This paper presents the design and the simulation of a modified Ku broadband double ridged guide horn antenna (DRGH) feed by a coaxial input. On board the satellites, the horn antennas play an important role in the wider bandwidth services. Telecommunication satellite horn antennas are need due to the additional necessary bandwidth. Advantages of using this type of antenna are: a wide bandwidth to operate over, adequate directivity, high power and its simple construction. Traditionally, the most desired electromagnetic characteristics of this antenna are achieved by empirically finding sizes for different parameters. The optimized shape and dimensions of the antenna are determined in order to meet the specifications of a satellite communications scenario. For this a suitable taper for the ridges in the horn was designed and its impedance variations along the horn were shown. A step by step method is presented for the design of the DRGH antenna. In order to have a clear view regarding the effects of different parameters, Ansoft HFSS was used for the simulations of the DRGH in the range of operating frequencies. The antenna performance is evaluated in terms of gain, directivity, polarization, radiation patterns, voltage standing wave ratio (VSWR) and field in plane E. The new design brings a higher gain and a good VSWR for the frequency range of Ku band. For a better matching of the feeder's characteristic impedance, the impedance bandwidth efficiency was broadened. The results show that the parameters near feeding point (the initial distance between ridges, the distance between the center of the probe and the cavity, the radius of inserted probe) play a significant role in controlling VSWR, gain, and in shaping the radiation pattern for high frequencies. By comparing it with the conventional version, the proposed antenna comes with a considerably better performance, smaller physical dimensions and less weight.

The aim of this paper is to evaluate a dual-band Multiple-Input–Multiple-Output (MIMO) Long Term Evolution (LTE) antenna for automotive applications. Such an antenna has an overall volume relatively small and can be fit in different locations on the vehicle. The compact planar structure facilitates that.The antenna is composed of two radiant symmetrical elements connected through a neutralizing line in order to cancel the reactive coupling. The radiating element consisting of a folded monopole and a rectangular metal patch can produce multiple resonant modes at 800 MHz (790–862 MHz) and 2600 MHz (2575–2635 MHz) for the geographical region of Europe. The proposed antenna is fed by using 50 Ω coplanar waveguide (CPW) transmission lines.