Tham khảo tài liệu 'advances in satellite communications part 13', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | New Antenna Array Architectures for Satellite Communications 169 MSS services are divided into two groups those that offer a regional coverage usually with GEO satellites and those which offer a global coverage based on LEO or MEO satellite constellations. Depending on the coverage there are some examples for MSS with regional coverage as the mobile satellite system MSAT in EEUU Canada and South America Optus in Australia N-Star in Japan Asia cellular satellite ACeS in Asia or Thuraya in the Middle East and in the North of Africa. While for MSS of global coverage there are some examples as Iridium ICO Global Communications Globalstar Teledesic etc. Evans 2009 Wu 1994 . Most of the MSSs work at L and S band new applications on satellite to mobile terminal links work at X Ku and Ka band and satellite to base station connections work at L S and C band. A number of applications is broad and lead terrestrial telecommunications market to offer a wider coverage high speed voice and data internet access SMS VoIP digital video broadcasting by satellite 2 DVB-S2 and digital video broadcasting satellite services to handhelds DVB-SH global position system GPS and Galileo security control and machinery monitoring on ships and aircrafts teleeducation or telemedicine. These modern satellite communications systems require new antenna solutions for base stations aeronautical applications or personal communications services PCS on-the-move Fujimoto James 2001 . Within these applications antenna array systems are potentially the best choice due to as discussed above its capability to perform electronically steering or beamforming increase the antenna gain and conform over curved or multifaceted surfaces the radiating elements. Portable antennas for PCS must be easy to install and mechanically robust besides compact and lightweight García et al. 2010 as the antenna array presented in Fig. . The design of antenna systems to provide high data rates for reliable PCS boarded on ships .
