8. Services, fraud and security in cellular and mobile communication systems. 8.1. Mobile phone and its capabilities.

The rapid development of mobile communication systems is continuously expanding the scope and quality of the services provided, making them massive and adapted to the individual needs of users.

Realization of new opportunities and new services is provided both by improving and implementing new technical solutions related to the creation of a global network infrastructure.

The development of the production technology of dual-mode terminals has been greatly simplified and the increase in their cost compared to single-mode (GSM 900 - single-mode, GSM 900/1800 - two-mode terminals) is insignificant.

This moment of transition from single-mode to dual-mode MS became a turning point in the development of mobile communications, since the emergence of dual-mode and multi-mode MS practically eliminated the issue of a single global standard that had been acute. The possibility of switching from one radio frequency band to another, switching from standard to standard (from GSM 900 to DCS 1800) or from satellite channel to cellular allows the subscriber to choose the type of service that suits him the most. Therefore, MS in the near future will, as a rule, be multi-mode, operating in networks of several standards.

Forecasts show that the decisive trend will be the merging of mobile communications with other information technologies. The process of merging fixed and mobile services continues, covering all new areas of human activity, including location and mobile commerce. There is an expansion of the list of services received from a mobile phone. These include paid information and reference services, various types of electronic payments (for example, payment for air, car and train tickets, parking, etc.), and in the future - all types of banking operations from mobile cell phones that in fact, they will turn into "pocket ATMs". Noting the multimedia of mobile systems, it should be emphasized that the services of these systems should be divided into two groups:

- non-multimedia (narrowband speech, low-speed data transmission, traffic circuit-switched networks);

- multimedia (asymmetric and interactive broadband services, video transmission and mobile Internet access).

8.1. Mobile phone and its capabilities Mobile phone.

Handheld mobile station (handheld) - a mobile telephone set (MTA) has typical dimensions (130x60x25) mm with a mass of 100 ... 200 g or less together with a power source.

On the front side of the simplest mobile phone there is a small display (usually liquid crystal), which reflects the telephone number to be dialed, menu items and other information.

An antenna with a length from 20 to 60 mm (in some types of MTA it may additionally extend to 50 ... 150 mm) or be located inside the case may protrude from the upper part of the MTA.

All control of the MTA is done with the help of the keys (keyboard) of the dial pad. With them, you can turn on and off the MTA; dial the desired subscriber number; write information to memory and read it; change the mode of operation of the MTA, etc.

On the front side of the MTA there are also a speaker (in the upper part); microphone (at the bottom); sound source (bell).

On the back of the MTA is mounted a power source and a SIM card.

Typical operating time of a fully charged battery is: talk time up to 5 hours; standby call up to 20 ... 50 hours. Typical battery charge time is 1 ... 6 hours.

At the bottom of the MTA, there are usually jacks for connecting a portable charger that allows you to charge the battery without disconnecting it from the device and not turning it off. In addition, infrared and bluetooth are provided.

Among the MTA accessories are hands-free kits (hands-free) with a speakerphone for using the MTA in a car without taking your hands off the wheel and special chargers for charging from the mains or vehicle electrical system (via the cigarette lighter socket).

The main characteristics of the most simple and cheap non-multimedia GSM mobile phones, produced by various manufacturers:

1) the output power of the MTA transmitters lies within (0.6 ... 2) W in the maximum mode of operation;

2) the number of lines on the display (2 ... 6);

3) the ability to transfer data using a PC card-modem;

4) the ability to enter a code to prohibit the use of another SIM-card;

5) work with a standard battery in talk / standby mode: 1/20 ... 10/100;

6) MTA mass ranges from 99 to 275 g;

7) the ability to automatically answer the call.

When purchasing MTA to work with it, the “Operation Manual” is attached, in accordance with which the preparation for use, battery charge, switching on and operation with MTA is carried out.

Summarize the minimum set of functions MTA:

1) call, answer call;

2) re-call the last number dialed;

3) accelerated dialing;

4) call the mailbox voice mail;

5) electronic notebook - phone list, clock, calendar, calculator (up to 250 phone numbers and names);

6) menu list;

7) phone protection;

8) network selection;

9) sending DTMF signals (Dual Tone Multi Frequency) - two-tone multi-frequency signaling, etc.

A wide range of GSM mobile phones can be found in branded and promotional materials of various companies that supply them to the telecommunications services market (Nokia, Siemens, Ericsson, Motorola, Samsung, Philips, etc.).