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Cell phone appeared in our lives, just like any other high-tech product, rather quickly. Just as before the VCR, camcorder or computer, he gradually mastered the progressive minds of the public and became an attractive and prestigious technical means available to most Russians only in dreams. If you recall the price of the first contracts (telephone, down payment and tariffs, etc.), many of them seem implausible - now that money can buy, if not new, it is quite a decent used car. However, over time, and this helped a lot of crisis in August 1998., A cellular telephone (PT) has become available not only for organizations, but also for individuals. Today, the accessibility and availability of our families can be compared with the VCR or computer. Do not have to be an analyst to confidently predict future CT - this kind of devices in the near future will be for many a natural and indispensable companion. The need for mobile communications in most regions of Russia can be implemented within days - it is enough to conclude a contract with the mobile operator to provide a specific group of services and there to buy a cell phone. However, selecting a cell phone even for people with higher technical education is not a simple matter. And it's not his particular technical complexity or diversity of models (for standard GSM-900/1800 them over 50). It is difficult to imagine that when selecting a color TV you first asked to choose to use standard (SECAM, PAL or NTSC), and then to television itself. This absurd situation has arisen in the apparent connivance of the technical and irresponsible policy of the state, led to the consumer on his own responsibility must determine what standard is used in cellular communications, and with it the company - operator. In fairness, we note that most modern TVs allow you to view the program in several standards. Over time, cell phones should be available, also operating in several standards (the company Ericsson announced the work being done in this direction). K 2002. supposed to create devices based on the standards of third generation mobile communications to unify all of the region. In this article we assume that an operator (standard for cellular communication), the reader proceeded directly to the choice of cell phone (CT). However, today it's not as easy as it might seem at first glance. For example, when choosing a computer, monitor or printer can help you publish in various journals. They fundamentally and technically literate considered novelties, their parameters and characteristics. With regard to cell phones, despite the growing interest of readers, unfortunately, are not so many books and articles that allow clear and evaluate a particular model and its consumer quality. Must be noted that publication, living on income from advertising, not taking responsibility, and the reader or do not know about the shortcomings of a particular model, or critical information will be embedded in a diplomatically "wrapper" that not once have agreed with the manufacturer or distributor specific device. And even more unlikely that the description of the device had a list of features and services, which it does not. Many publications are written by poets rather than professionals - judge for yourself: "This is the first phone .....which not only Russified menu, and make the Russian language a priority. "- would be better off this wonderful phone Russified author of the text," In today's cell phones, a GSM user identity, together with his phone number hidden inside the SIM-card ... "- but the personality author of the text can not hide; measurements showed a rigid dependence of the capacitance standard battery of current consumption. " - A discovery that could shake the foundations of electrical engineering, developers not only agreed to his response to a standard phone, but have taken measures to compensate for the failure ... "- by what means they align their response would have been interesting to learn not only how many readers otolaryngologist;. . of controlling a basement, where mobile communications was absent, NOKIA confidently contacted ... "- a fundamental term" controlling basement, first introduced in the technical literature by the authors. It seems that the presence of instrumentation authors generally know nothing; "Original acoustic design, the phone ... "- yet another new term," thanks to the work of designers apparatus pleased to take over ... "- no comment," a slightly rounded shape body easily falls not only in women but also children's pen - you might think that the main problem is the choice of cell phone for their child. After reading the "analytic" material containing such revelations, and all of the above fragments were taken not from the humor magazine, and publications that claim to the role of a competent adviser, the reader is unlikely to be able to choose the unit responsible his or her abilities and desires. So the problem of selecting the type of ST exists. What does the manufacturer, and that a particular subscriber, what to choose and why? "Let's try together with the reader to understand what PTs are now sold and to whom?" And here is the first stop on such things as range . The range of the manufacturer PT conditionally may consist of the following classes (groups): a simple, affordable for beginners subscriber cost model for advanced users; multi-model business class, a model based on the most modern technology - luxury, model, designed to operate in difficult field conditions. Each class is designed for a specific group of buyers and has its own characteristics. When you create a lineup of developers as guided by the corporate client, and at the individual buyer, offering several options for performance optimization product, taking into account the specific parameters, such as duration of continuous operation, or weight, or the possibility of voice quality. To really sort out the product line, we consider the model number CT standard GSM-900/1800 the example of Siemens (shows the average price, including VAT). Model A35 - a simple device with the basic minimum set of features and services for the novice caller, the reasonable price ($ 100). S35i model - cost model for advanced users with the possibility of a mobile office at its base, a reasonable price ($ 150). Model S35i - multifunction machine for business ($ 250). Model SL45 - tiny phone "de luxe" with a maximum set of features ($ 500). Model M35 - a shock-resistant waterproof housing designed for those who lead an active lifestyle ($ 240). Features range of each company determine the presence in its composition of a particular class of devices, but the general approach and the desire to orient the product on a certain group of customers is obvious. renewed Models 1 - 2 times a year and the price is in a class of the new model is undoubtedly higher . The first natural step in the selection of CT is to determine the class of your cell mate. A reasonable balance of price and functionality for some, the greatest opportunities for others or something else will formulate specific requirements for cellular phone. To select a specific device will require knowledge of its technical characteristics. Since we are talking about mobile phones, in some cases, the foreground weight, size, duration of continuous battery life. Ease of use (display size, image quality, ergonomic keyboard) will also be of considerable importance.Choosing the CT, it should be noted that the cell phone offers you a choice of additional services (call forwarding, conferencing, etc.) in contrast to conventional wireline telephony, which is just beginning work in this direction. Thanks to the microprocessor, CT can also act as a calculator, notepad, calendar and even playing the CPU. In addition, many CT provide the ability to hot link to a laptop or handheld computer, allowing you to send / receive data and faxes. Note that the design of the device is essential for many, if not essential. But the question (the analysis of design of modern CT), we reserve the framework of this material. In order to determine your individual requirements acquiree CT in the presence of such a broad range of characteristics, parameters, functions and services we offer to allocate among these groups:
- basic characteristics and parameters;
- parameters of the display and keyboard;
- security features;
- functions and services supported by the operator;
- memory function;
- additional features;
- configuration items.
Basic characteristics and parameters
Weight (city, usually with standard battery). Here is a little trick. Several companies give a lot of the little battery (Slim), whose capacity is lower than the standard, but the time of talk / standby provides for a standard. Dimensions (mm) (with standard battery) / Volume (cc).. Duration of talk time without recharging (min.). The duration of standby battery life (hours). Here we want to draw attention to a battery (standard or large) are given these values. In a number of brochures can be found very attractive values, but the fine print will be noted that this data for a large battery. Type of battery as standard / Capacity (mAh). Most modern batteries are equipped with ST-type Li-Ion (Li-Ion). They are lighter and at the same volume and mass have a greater capacity than previously used lower-cost Nickel-Metal Hydride (Ni-MH). Besides batteries, such as Li-Ion does not have "memory" effect, ie does not require full discharge before recharging, which reduces the time required for charging, and simplifies the charger. The latest achievement in this area are battery type Lithium-Polymer (Li-Pol), having at the same dimensions as the Li-Ion high capacity and lower weight. Charge Time (min.). Typically in the range 2 - 3 hours. Operating temperature range. If you intend to work with ST at low temperatures, one should bear in mind that the battery capacity while decreasing, ie, reduced operating time.
Display Options
Type. Current displays include the graphic type, ie can play both alphanumeric and graphical information, such as images that accompany a particular SMS-text messages. Some models, mostly to the 1999 release have alphanumeric displays, the possibilities are limited. If the display of the image type, its main consumer option should be considered - the resolution of which determines the number of points - pixels, forming a matrix. Naturally, the larger the display size and resolution of AxB (pixel), the clearer the information is reproduced. Today is dominated by monochrome displays. Color displays - until a rarity in CT. Following the model of Siemens S10, such exotics on the market did not appear. Some models provide dynamic change font sizes, depending on the amount of reproducible data. For many customers is essential illumination color. But today you can find PTs whose highlighting color changes according to the choice of its owner, or can be programmed for a certain color depending on the situation, for example, call a subscriber whose number is entered in the notebook into a specific group.
Keyboard Options
Redial the last number dialed by pressing a single button. This function creates a certain comfort when typing. The number of speed dials (the latter: incoming / outgoing / from the notebook). If before this feature was only CT Business Class now speed dial in models of consumer class - element binding. Locking the keypad from the menu.Very useful function in different situations. Mute button. Allows for the rapid increase in confidential dialogue. Availability of technology speed dial (like T9). Typing, for example, SMS messages, this technology allows faster set. Introducing the first characters, the user sees on the screen the word that the program extracts from the dictionary stored in memory ST. This will be the most probable word corresponding to a given set of first symbols. While the system speed dial worked for the Latin languages. Cyrillic support in the recruitment of SMS. To enter the Cyrillic alphabet in a notebook, and in the SMS-text messages, the company is the manufacturer must modify the software ST. At present, this possibility is not all vehicles.
Security features
PIN code - 4-8 digits - the identification number of the person intended to enter the network and activate your subscription. PIN2 code - provided by the operator and is used for special functions. PUK (PUK2) code - a personal unlock code, if the owner has forgotten the PIN (PIN2) code, or it incorrectly entered three times, with the help of the PUK code phone will be unlocked. Lock SIM card (access via PIN code) - if enabled, the PIN code must be entered each time the apparatus. Key lock - the ability to lock the keyboard hardware. Encoding of information - security techniques technologies GSM, designed to provide authentication, encryption, voice and data traffic. Basis kriptoarhitektury are four basic algorithms: A3, A8, A5.1/A5.2. The last two algorithms provide, respectively, "strong" and "weak" encryption. Blocking calls outgoing or incoming - eliminates work with your device a third person. Fixed set of numbers - the list of numbers given by the subscriber. Lock all the negotiations, except on the list (FDN). Useful feature, especially for dispersed subscribers. Availability of confidential numbers in memory (Closed user group - CUG) - access to these numbers is possible when you enter an additional password.
Functions and services supported by the operator
Short Message Service (SMS). The service is supported by the majority of operators are usually free service. Maximum number of alphanumeric characters in one message - 160. The latest models allow you to exchange messages and longer - up to 640 characters, but this feature does not support all operators. You can find out the time and date of receipt of the communication, it is also possible to determine the number and the name of the person who sent the message. Voice messaging system (voice mail - Voice mail). The service allows you to not lose a challenge if you can not receive and automatically sends it into a personal bank voice mail. Depending on class of service, number of posts 10 - 20, the maximum length of posts 20 - 30 sec. Can automatically reply to a voice message, and forward the message. This service is available for active service, "Forward." Support for WAP. In ST there are a number of technical limitations that prevent the use of standard, well-developed Internet technology. To overcome them was a family of new standards, united by a common name - the technology WAP. WAP - Wireless Application Protocol access to information on the Internet, for devices with limited screen size, small memory and low speed network access. The key elements of technology are the WAP-browser (Internet browsing program), WAP-gateway server and WAP-content (www.wapforum.com). WAP protocol provides access from mobile phones to the WEB-pages, filed with the language of WML. The latest version of WAP - v.2.1. What opportunities will the subscriber, including cellular phones, supports WAP? First, the news service (international, national, regional). Further, the wireless office - look up subscriber business information on the server of the company, zaviziruet necessary documents, etc. Banking applications - the state accounts, pay bills, transfer money, all these operations a subscriber performs in the WAP-server of the bank. Supports SIM Application Tool Kit (STK) - Technology-based resource short message service (SMS), a component of standard GSM.Allows holders of mobile phones to make transactions in electronic commerce systems. Personal information stored on SIM-card user, is used in security systems and identification. Compared with the WAP STK is more reliable for banking services. Provides the greatest opportunity STK Class 3. Data transfer. In addition to accessing the Internet and e-mail directly from the CT, you can connect the laptop to the phone or PDA. Data exchange rate (Kbps). At present, the GSM provides exchange rate 9.6 or 14.4 Kbps. The latter value is not supported by all operators. For the majority of CT is regulated by the rate of 9.6 kbps. Sending and receiving faxes. In addition to direct data CT allows to work with fax messages. Usually used for this notebook or Pocket PC. Support for conference calls (1 +5), (MTPY). This service allows you to organize a teleconference mode - you can simultaneously connect with a group of up to 5 people, and to arrange a meeting. Two numbers on one phone (ALS). This service allows subscribers to enter into a contract with the operator, for the acquisition of two telephone numbers. One of them you can tell co-workers, other - relatives. Calls made to both numbers, and come to a PT. Determination of caller ID, called AON, (CLIP). This service is only available for digital networks. CLIR caller (CLIR). The service allows subscribers to block certain of its facilities waiting / call hold (pending and waiting for the call). This mode allows you during a conversation with the caller to call another subscriber or to answer an incoming call again, talking alternately to two subscribers. Call Forwarding. Possible types of call forwarding: all calls, all calls when the line is busy, all calls when no answer, all calls when the phone is switched off or out of radio coverage. Call Barring (Call Barring) is a package of services: a ban on all incoming and outgoing calls, a ban on outgoing international calls; ban on entering, a ban except for calls within the network. Coding of speech. Modern devices support a mode - a full-size speech coding (EFR - Enhanced Full Rate). Naturally, the quality of the reproduced speech is increased, but the trouble is that in Russia, not all operators support this mode.
Memory Functions
Reference numbers and names (Phone book). Usually numbers are stored in the SIM-card. In modern CT provides additional memory directly into the unit. For example, in a model of Nokia 8850 in memory store 250 numbers and the same number on SIM-card. Memory organization in groups. In some models may be grouped numbers, for example, business partners and relatives. Find phone numbers in the phonebook the phone. Conveniently, if the search is possible both by name and by number. Remembering the past to a number (dialed / incoming / missed). The maximum length of a notebook name / number. This is important if the subscriber uses an additional code for network access another operator. Check free memory cells. Feature allows you to assess the availability of affordable recording numbers in a notebook. Ability to complete cleaning of the phone book. A useful feature for emergency situations, and for updating the phone book.
Additional features
The presence of the recorder to record the current information / recording time (sec). Many models of business-class voice recorder has a function and make it possible to record a fragment of the talks or write your comment. Typically, the recording time of 50 - 100 sec. Several models allow you to set the recording quality. Naturally, the higher the quality, the smaller the interval of recording time. Opportunity to record a telephone conversation (work in voice recorder mode) / Record Time (sec). It is worth to note that not every model has a voice recorder function, allows you to save a fragment of telephone conversations. The ability to play recordings from the recorder during a conversation. Useful feature allows your companion to listen to the recording, made in advance. The possibility of transferring the recorded comments on the PC. This feature allows you to convert the recorded conversation in a form understandable to the PC, for example, sound file format (. Wav).When connecting to PT and PC, special software will provide the transmission of a file (call) in the PC memory. The built-in browser. Viewer web pages - the browser is part of the software (SW) ST. Usually this is the WAP-browser. However, there are browsers that lets you view both WAP-pages and standard HTML pages. For example, the model Benefon Q, browser MS Mobile Explorer, supports both protocols. The built-in mail client. For receiving / sending e-mail software is included in the appropriate program. Here, the manufacturer may specify the type of supported protocol - POP3 (most common), or IMAP4 - a perspective. Note that the e-mail reception is possible and based on short message service (SMS). The presence of shakes in a standard configuration. Vibrate or silent call allows in some situations, to disable call your ST. If you receive a ringing tone instead of the usual call to subscribers feel subtle vibrations ST. The presence of the organizer - usually daily, which is using the alarm function notifies you of the upcoming meeting. Ability to synchronize Address Book / Organizer with PC software (like MS Outlook) - This function is useful for those who actively use computer equipment to conduct business. A number of modern CT with organizer, for example, Benefon Q, do not allow to sync with standard software, so you have this procedure done manually. The presence of a calculator, alarm clock, games - these functions do not require comment. Indication of date and the current time - a calendar and clock undoubtedly useful. Indication of time received calls: received / missed. Ability to dial - this function is known to all holders of the modern digital phones. Can be programmed to redial the interval from one minute to tens of minutes. The same service can offer operators, but it involves additional cost. Set (activation) of the votes (the number of rooms). Speech recognition technology to automate the recruitment process. Pre-enough "to train" your phone by saying the name of the subscriber, such as Hamlet, which is written into memory. This is the name you assign a specific number. In what follows by saying a command like "set" and the name of Hamlet - the phone will automatically dial the given number. Possible number of rooms, depending on the type of CT - 5 to 20. Voice control menu (the number of teams). Similarly, a set of numbers, can be suppressed voice command, enter a specific Menu ST. If we remember that the menu system is a conventional device 4 - 5 tier, and each level of 4 - 6 points, saving time in the presence of voice control is quite significant. Creating a custom menu (User Profile). This possibility will simplify access to the functions menu, which you use most often. Function Help (HELP). Useful especially when dealing with CT for the first time, as can quickly tell the sequence of actions to perform the requested command. Audible alarm call duration. This feature allows a subscriber to program the timer, which during the conversation will be with a certain interval, for example, 30 seconds. beep. For the budget conscious users, this function is clearly worthless. Audible alarms for low battery. Standard function, usually accompanied by the appearance of the corresponding icon on the screen. Notifies the discharge at the most inopportune moment. Depending on the model and manufacturer, time to turn off is 5 - 20 minutes. Expenditure control. There may be a number of options: Counter duration of the last call and total call counter, check the value of a call and check the remaining credit (Translation of conversation for money). To recalculate the money necessary first program cost per minute of conversation in accordance with the chosen tariff plan. Adjusting the speaker volume / tone. Could be done directly with the key (button), and from the menu. Number of ringtones / number of additional signals. ... Ability to create your own ringtones. Can be programmed as a favorite tune, or enter a melody previously recorded on a computer or found on the Internet. Handsfree (Speakerphone).This feature allows you without leaving your desk to chat with a friend, or listen to a conversation in a quiet room, put the phone on the table. Ability to automatically answer the call (avtopodnyatie). This feature allows you to start a conversation without clicking on the "Reply" button. Automatic activation is useful when a call is received by the subscriber, sitting behind the wheel of a car. The built-in MP3 player. Convenient for fans of sound. Allows you to pre-load a few tunes and if you want to listen to them.
Configuration items
Type of SIM card (Subscriber Identity Module). SIM card - the constructive, which is integrated circuit. In memory chips included data that define an individual code ownership ST. In the absence of SIM cards, the phone does not work. In addition, the SIM-card can be used to organize the notebook user. In today's SIM cards (such as Plug-in, miniature, embedded in the body) can store up to 250 entries (phone numbers). In vehicles, produced before, use the SIM card type Standart, performs a similar function, but has great size and inserted into the body. The built-in fax modem. The built-in so-called GSM-modem allows the use of CT for the transmit / receive data and faxes. This device differs from conventional fax modems, as it works wirelessly in the network GSM. GSM-modem allows you to work both directly with the data and combine CT with a laptop or handheld computer, to organize a mobile office for receiving / sending E-mail, faxes, and receive data from the Internet. Ability to connect to a PC through the card PC card / RS-232C. For this purpose, ST connector shall be provided, attached to a special cable with an appropriate output, such as a laptop. Typically, such a cable is not supplied with CT, but is included in the accessory kit, produced by the manufacturer. Until now, the unification of connectors and cables, by analogy with laptops in the industry CT did not happen and the search for the desired cable or order take some inconveniences. Therefore, if you intend to organize a mobile office, should I buy the cable at once. Infrared interface IrDA. Used for wireless communications ST and PC, usually a laptop or Pocket PC. Transceiver infrared provide high speed data exchange (up to 4 Mbps). However, the range of this interface is limited (up to 1 m). In addition, the IR receivers are sensitive to the direction of signal arrival - departure no more than 30?. Recall infrared radiation conditions require "line of sight." Software. It can either be included or optional. For example, the bundle model Ericsson R320s is a CD. It finds the subscriber: infrared drivers for Win95/98, a software package Ericsson Data Communication Suite for Win95/98, SMS and phone book phone software tasks the phone directly from the PC. In addition, this CD is an electronic version of the manual format. Pdf. Ibid - Demonstration and training program, illustrating the operation of the proposed software. Ability to connect the headphones / external microphone. Possibility to connect the car kit HandsFree. This feature is required if you have a habit of not disable CT while driving. Antenna type: fixed / telescopic / exchangeable. The most widespread fixed antenna. It comes in two types: interior and exterior. Reception quality in both cases does not depend on the type of antenna. For example, recent models from Nokia has an internal antenna. Telescoping antenna, used in some models, allows in some cases to optimize the output stage, improving the transmission in the area uncertain of the apparatus. Removable antenna involves the ability to connect additional antenna, whose parameters improve the functioning of ST in the area of uncertain reception. In some devices, for example, Benefon "DRAGON" Included are two antennas, the subscriber may set depending on the quality of coverage, in which it is located. Ability to connect an external antenna.If you want to use CT in uncertain reception area, to increase the stability of it is expedient to choose the model that has extra high slot. You can connect an external antenna. The authors, translation: