In this paper we give an overview of the major issue of Mobile Computing describing the Technical Design, Network Design .We also explain the History of Mobile Devices, Mobile Computing in In-Vehicle Computing and Fleet Computing .It is also necessary to know the Advantages and Disadvantages of using Mobile Computing so that they have been explained in this Paper along with the Description of Wireless LAN architecture using BSS. Keywords: - Mobile Computing, Basic Service Set (BSS), Local Area Network (LAN), Direct Sequence Spread Spectrum (DSSS), Media Access Control (MAC) Introduction to Mobile Computing Mobile Computing is a generic term describing your ability to use technology ‘untethered' that is not physically connected, or in remote or mobile (non static) environments. The term is evolved in modern usage such that it requires that the mobile computing activity be connected wirelessly to and through the internet or to and through a private network. This connection ties the mobile device to centrally located information and/or application software through the use of battery powered, portable, and wireless computing and communication devices. This includes devices like laptops with wireless LAN or wireless WAN technology, smart mobile phones, wearable computers and Personal Digital Assistants (PDA's) with Bluetooth or IRDA interfaces. Types of Mobile Computers:- Many types of mobile computers have been introduced since the 1990s, including the: · Laptop computer · Subnotebook · Personal digital assistant (PDA) · Portable data terminal (PDT) · Mobile data terminal (MDT) · Tablet Personal Computer History of mobile devices Originally, electronic devices such as radio transmitters, wireless communications systems, and the like, were base stations, operated at fixed locations, typically with large antenna towers. Widespread use of automobiles gave rise to smaller devices operating at 6 volts.
In the 1950s, the transition to 12 volt automotive electrical systems gave rise to a large number of 12 volt devices, such as two-way radios, referred to as mobile rigs. A large industry, with companies such as Motorola sprung up to support the growing need for mobile devices, such as taxicab radios, police radios, and other 12 volt under dash equipment, as well as trunk mount systems. Today there are a wide variety of mobile computing platforms, including dash-mount VGA displays, and computers that can provide GPS and other navigation functions for automobile users. Base-Mobile-Portable hierarchy In ham radio, there is a base-mobile-portable hierarchy, as follows: · Base station: fixed location, incorporated into a building or other architecture; · Mobile: attached to or in a vehicle or used by a mobileer; Portable: worn or carried. (The word "portable" derives from French "porter" = "to wear", but also includes handheld devices such as handy-talkies, walkie talkies, handheld computers, as well as wearable computers). Mobile Computing: In-Vehicle Computing and Fleet Computing Many commercial field forces deploy a rugged zed portable computer such as the Panasonic Toughbook 29 with their fleet of vehicles. This requires the units to be anchored to the vehicle for driver safety, device security, and user ergonomics. The rugged laptops are rated for severe vibration associated with large service vehicles and off-road driving, and harsh environmental conditions of constant professional use such as in EMS, fire and public safety.