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Satellite communications
Published in Matthew N. O. Sadiku, Optical and Wireless Communications, 2018
Several commercial satellite applications are through earth stations at fixed locations on the ground. The international designation for such an arrangement is fixed satellite service (FSS). FSS provides communication service between two or more fixed points on earth, as opposed to mobile satellite services (MSS) which provide communication for two moving terminals. (MSS is discussed in the next section.) Although ITU defined FSS as a space radiocommunication service covering all types of satellite transmissions between given fixed points, the line between FSS and broadcasting satellite service (BSS) for satellite television is becoming more and more blurred18. FSS applies to systems that interconnect fixed points such as international telephone exchanges. It involves GEO satellites providing 24-hour per day service.
Fixed and Mobile Antennas for Satellite Communications
Published in Lal Chand Godara, Handbook of Antennas in Wireless Communications, 2018
Marek E. Bialkowski, Nemai C. Karmakar, Paul W. Davis, Hyok J. Song
Opposite from FSS and BSS, MSS satellites are designed to provide mainly voice transmission services for users with mobile transceivers featuring low power and low antenna gain.4,5 This means that the downlink transmit power density has to be much higher per voice channel than for a typical FSS system. Also because of the small bandwidths that are available in L- and S-band, a high degree of frequency reuse has to be applied to serve the needs of the many users of the MSS system. To achieve these aims GEO, MEO, or LEO satellite systems can be used. Present systems use GEO satellites, which transmit voice, fax, or data between a mobile user, located in a remote place, and the Public-Switched Telephone Network (PSTN). The L- or S-band is used for getting the communication link between the user and the satellite, whereas the overall satellite telecommunication traffic is handled by Ku-band (or C-band as is the case of INMARSAT). Examples of such GEO MSAT telecommunications systems include INMARSAT (global system), and Mobilesat (Australian), AMSC (North America), and N-star (Japan) (domestic satellite systems).
Satellites
Published in Mohammad Razani, Commercial Space Technologies and Applications, 2018
FSS—A radio-communication service between earth stations at given positions, when one or more satellites are used; the given position may be a specified fixed point or any fixed point within specified areas; in some cases, this service includes satellite-to-satellite links, which may also be operated in the inter-satellite service; the FSS may also include feeder links for other space radio-communication services.
Design and experimental validation of customised fractal FSS
Published in International Journal of Electronics Letters, 2023
Anuradha Sonker, Tushar Goel, Amalendu Patnaik
In order to experimentally verify the results obtained using the developed methodology, the unit cell structure of FSS2 was chosen to make the FSS array because of the small size of the patches facilitating easy fabrication. The lower stop band frequency of 5.5 GHz of this FSS lies in the C-band, whereas the upper one of 15.6 GHz lies in the Ku-band. The size of a unit cell of FSS2 is 6.1 × 6.1 cm2 with periodicity = = 61 mm in x and y-directions, respectively. The FSS array was fabricated on two A4 size PCB sheets with = 2.2 and height of 1.588 mm. The overall size of the printed area is 36.624.4 cm2 that contains 24 ( = 2 × 3 × 4) unit cells. The size of the FSS sheet is 40 × 29 cm2 ( = 2 × 20 × 29 cm2). A photograph of the fabricated dual stop band FSS is shown in Figure 5.
An FSS Based Broadband Elliptical Tree Shaped Antenna with Augmented Gain for Wireless Applications
Published in IETE Journal of Research, 2022
Ananda Babu Devarapalli, Tamasi Moyra, B. T. P. Madhav
Figure 21 explains the gain augmentation. The radiation pattern of the designed antenna without the FSS structure shows that the antenna radiates both above and below the plane. The FSS must be at least λ/2 below the transmit/receive antenna to function properly. Reflection occurs when an antenna is set at a specific distance above an FSS. A direct outgoing wave from the antenna in the direction of the FSS reflector is augmented by this effect. Using the FSS reflector increases the antenna’s gain because the two wave components combine in phase, suitable for the antenna. If is the transmitted wave phase from the antenna, is the reflected wave phase by the FSS, and is the free space propagation phase delay between the antenna and FSS, then H = distance between the FSS and the antenna, C =velocity of light, should be zero or an integral multiple of 2π is required for phase coherence [28]. For better gain and impedance matching at both operating frequencies, as shown in Figure 22, the spacing between the antenna and FSS layers has been optimized. A distance of around 14 mm is used in the parametric study, which corresponds to the resonant frequency λ/2.
A low profile patch antenna for Ku-band applications
Published in International Journal of Electronics Letters, 2021
Gurpreet Singh Saini, Rajeev Kumar
To accomplish the constraint of environment and space, the low profile, small size, lightweight and dual-band microstrip patch design are appropriate for satellite application. For satellite applications, the International Telecommunication Union (ITU) splits the world into three regions for efficient organisation of spectrum. In region 3, the allotted frequency band for fixed satellite service (FSS) in receive mode and transmit mode is 12.2–12.7 GHz and 14–14.5 GHz, respectively. Whereas, the allotted frequency band for direct broadcast service (DBS) in receive mode and transmit mode is 11.7–12.2 GHz and 17.3–17.8 GHz, respectively. The proposed design meets the spectrum necessity of region 3 for FSS and DBS in receive mode and FSS in transmit mode.