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Discusses wireless data networks. Concept of internetworking; Functions of the Open System Interconnection (OSI) reference model; Purposes of each layers of the OSI model.

Any continuous-time analogue signal can be converted into a digital signal by making discrete both the time and the amplitude axes. The process of making the amplitude axis discrete is called quantization. It consists of dividing the amplitude axis in contiguous intervals and in associating to all the amplitudes within any interval a single amplitude value chosen among them. A regenerator receives the incoming pulse stream and transmits a new regenerated pulse stream that replicates the original sequence as closely as possible. To regenerate the signal, timing information must be known so that the regenerated pulse stream can be transmitted with the proper intervals between the pulses.

In the future, radio communication systems will offer different services through single user equipment; furthermore, it is expected that different radio communication systems will merge into one universal communication system. Today, there are two known concepts for providing wireless communication services: terrestrially based communication systems and satellite communication systems. Each concept has its specific characteristics, and consequently, advantages and disadvantages. The main disadvantages of terrestrially based systems are: poor radio channel quality, Rayleigh fading limits the cell radius and transmitted data rate and; and Terrain shadowing causes gaps in radio coverage.

Chapter 2 (93 pages) explains the fundamentals of radio transmission like attenuation of radio waves, propagation over flat terrain, multi-path fading, statistics of the transmission channel, reflection, diffraction, RMS delay spread, shadowing, interference caused by other systems. Models to calculate the radio field, namely empirical models and diffraction models, ray tracing techniques and the famous Okumura/Hata model are introduced. [ABSTRACT FROM PUBLISHER]

Chapter 17 reviews the existing routing algorithms for wireless networks of nodes that are not aware of their geographic positions. Routing the message (finding a path between a source and a destination node) is a basic data communication protocol in mobile ad hoc networks, consisting of hosts that communicate without the assistance of base stations. [ABSTRACT FROM PUBLISHER]

The presence of scaling behavior in telecommunications traffic is striking not only in its ubiquity, appearing in almost every kind of packet data, but also in the wide range of scales over which the scaling holds. It is rare indeed that a physical phenomenon obeys a consistent law over so many orders of magnitude. This may well extend further, as increases in network bandwidth over time progressively "reveal" higher scales. [ABSTRACT FROM PUBLISHER]

Not all carriers operating near the same frequency band offer essentially the same coverage choices. Design trade-offs are made between area coverage and its close cousin, building penetration, versus subscriber capacity. These trade-offs flow from fundamental decisions on channels allocated for data versus control, channel reuse philosophy, base station quantity and location, transmit power levels, FM capture exploitation, bit rates, and message redundancy-to name just a few. These trade-offs are discussed in this chapter. [ABSTRACT FROM PUBLISHER]

The airlink subsystem is defined as the span between the user host's connection point and the subscriber unit. It includes the service provider's message switch/area controller, base stations, and the radio modem. There are at least four current philosophical control approaches: (1) decentralized, (2) partially decentralized, (3) partially centralized, and (4) centralized. Each of these approaches is examined in order, from highly decentralized to highly centralized. [ABSTRACT FROM PUBLISHER]

The variety of public network choices cited in the preceding chapter leads some potential users to despair at what seems a plethora of alternatives. Actually, specific user requirements can quickly eliminate many network candidates. This permits a more straightforward assessment of realistic alternatives. A few of those salient user characteristics are discussed in this chapter. [ABSTRACT FROM PUBLISHER]

This chapter is a simplified look at some nonhardware technologies, protocols, and communication standards that drive both network and device development. The focus is on modulation techniques, error detection/correction, and data compression. [ABSTRACT FROM PUBLISHER]

Packet systems are the least uniform and most complex. Examples of the enormous range of products are presented in this chapter, in increasing degrees of complexity, beginning with the client modem and working through servers and gateways to the host application. [ABSTRACT FROM PUBLISHER]