Antennas for multiple spot beam satellites

Abstract

Ka-band payloads are becoming more and more popular for satellite communication. The wider band width in Ka-band allows a better satisfaction of the increasing demand for capacity. In addition to the use of more resources, a more efficient use of the available resources will become key for a successful development of satellite communication services. Modern antenna concepts allow a high frequency reuse scheme and, therefore, an extreme efficient use of the most rare resource in satellite communication, the frequency band width. In this paper, we describe the design and the use of different types of such antennas.

Application of bifocal concept to dual reflectarray configurations for multi-beam satellite antennas in Ka-band

“…Current communication satellite antennas in Ka-band are required to provide a high number of overlapping spot beams, typically more than 80 for a pan-European coverage [1]. This factor, combined with the deployment of frequency and polarization reuse schemes, leads to an increase in the users' data rates and the overall capacity of the network, enabling the provision of high speed broadband services in Ka-band.…”

Energy‐efficient link resource allocation in the multibeam satellite downlink under QoS constraints

“…As the number of colors increases, the mutual interference reduces, leading to a higher value of GP. It is worth to point out that usually, at least a three-color scheme is employed [25], but also in the less practical two-color scenario, the proposed algorithm is able to improve performance with respect to the minimum required GP. Besides, the algorithm is adaptively scalable because even in the worst condition of operability, that is, with higher interference, it converges within a few iterations.…”

“…In this section, the performance evaluation of the multibeam satellite downlink previously described is carried out by means of numerical simulations. As case of study, a Ka band GEO multibeam satellite with Europe-wide coverage is considered, composed of N b D 60 beams, each of d D 170 km of diameter, single feed per antenna [25] with P max D 50 W over 36 MHz bandwidth per transponder [26]. Considering a transponder's efficiency, defined as the ratio between the radio frequency output power P max and the direct current (DC) input power P c (supplied by the solar panels and batteries), of about 33% [26], the power consumption is set to P c D 150 W. Figure 7a depicts the conventional four-color scheme here employed, where the Ka band is split in two contiguous subbands, termed B 1 and B 2 , and both H and V polarizations are employed on both subbands; Figure 7b shows how the multibeam pattern, according to the color scheme just described, has been generated in simulation.…”

<formula formulatype="inline"><tex Notation="TeX">$Ka$</tex> </formula>-Band Multiple Feed per Beam Focal Array Using Interleaved Couplers

“…Moreover, their implementation leaves little available room for other antennas addressing different services. Multiple feed per beam (MFB) focal arrays are good candidates for reducing the number of reflectors for similar performances [4], [7]- [9]. In MFB focal arrays, each beam is produced by a cluster of radiating elements, which are fed by an appropriate beam-forming network (BFN).…”

“…From the overlap of adjacent clusters, the radiating surface is enlarged without increasing the beam spacing. Moreover, MFB focal arrays allow producing spots using a single reflector [4], and consequently, only two antennas are generally required, one for transmitting data and one for the reception. However, the BFN used in MFB antennas are often difficult to design and are geometrically complex with a combination of many different couplers and phase shifters [4], [9].…”