Wireless communication systems are constantly evolving. System designers are continually developing greater numbers of features for both service providers as well as for the end users. In the area of wireless phone systems, cellular based phone systems have advanced tremendously in recent years. Wireless phone systems are available based on a variety of modulation techniques and are capable of using a number of allocated frequency bands. Available modulation schemes include analog FM and digital modulation schemes using Time Division Multiple Access (TDMA) or Code Division Multiple Access (CDMA). Each scheme has inherent advantages and disadvantages relating to system architecture, frequency reuse, and communications quality. However, the features the manufacturer offers to the service provider and which the service provider offers to the consumer are similar between the different wireless systems.
Regardless of the modulation scheme in use, the wireless phone available to the end user has a number of important features. Nearly all wireless phones incorporate at least a keyboard for entering numbers and text, and a display that allows the user to display text, dialed numbers, pictures and incoming caller numbers. Additionally, wireless phones may incorporate electronic phonebooks, speed dialing, single button voicemail access, and messaging capabilities, such as e-mail.
Subscribers' reliance upon their mobile terminals (such as, cell phones) and on wireless service in general continues to increase. The demand for and implementation of Emergency-911 and geo-location services for mobile terminals are two typical examples of this increasing demand. However, subscribers quickly learn that, once away from areas equipped with cells and base stations, their mobile terminals are no longer able to function. This lack of connectivity is a significant drawback of the prior art.