Satellite communications

• Authors: Matthew N. O. Sadiku
• Venue: The handbook of ad hoc wireless networks
• Year: 2003

Wireless communication is undergoing explosive growth, and satellite-based delivery is a major player. With the introduction of satellite personal communication services in the near future, an important step will be made toward the implementation of a global communication infrastructure.Satellite communications were first deployed in the 1960s and have their roots in military applications. Since the 1965 launch of the Early Bird satellite (the first commercial communication satellite) by the U.S. National Aeronautics and Space Administration (NASA) proved the effectiveness of satellite communications, satellites have played an important role in both domestic and international communication networks. They have brought voice, video, and data communications to areas of the world that are not accessible with terrestrial lines. By extending communications to the remotest parts of the world, satellites have helped to allow virtually everyone to be part of the global economy.Communication by satellite is not a replacement for the existing terrestrial systems but rather an extension of wireless systems. However, satellite communication has the following merits over terrestrial communication: • Coverage: Satellites can cover a much larger geographical area than traditional ground-based systems can. Satellites have the unique ability to cover the globe. • High bandwidth: A Ka-band (27-40 GHz) can deliver throughput of gigabits per second rate. • Low cost: A satellite communications system is relatively inexpensive because there are no cablelaying costs and one satellite covers a large area. • Wireless communication: Users can enjoy untethered mobile communication anywhere within the satellite coverage area. • Simple topology: Satellite networks have simpler topology, which results in more manageable network performance. • Broadcast/multicast: Satellites are naturally attractive for broadcast/multicast applications. • Maintenance: A typical satellite is designed to be unattended, requiring only minimal attention by customer personnel. • Immunity: A satellite system will not suffer from disasters such as floods, fire, and earthquakes and will therefore be available as an emergency service should terrestrial services be knocked out.Of course, satellite systems do have some disadvantages. These are weighed against their advantages in Table 8.1 [1]. Some of the services provided by satellites include fixed satellite service (FSS), mobile satellite service (MSS), broadcasting satellite service (BSS), navigational satellite service, and meteorological satellite service.This chapter explores the integration of satellites with terrestrial networks to meet the demands of highly mobile communities. After looking at the fundamentals of satellite communication, we will discuss its various applications.