How Ringtones Work

Like computers, cars and PDAs,cell phonesstarted out as purely functional pieces of technology, but quickly evolved plenty of fun frills to keep their users entertained. Today's phones have built-in video games, specialized background pictures, switchable faceplates and, of course, customizable ringtones.

A ringtone version of your new favorite song does serve some purpose, of course -- it lets you distinguish your own phone's ring from other phones ringing around you -- but more than anything else, it's a chance to add personality to technology.

在本文中,我们将看到手机铃声都是什么about and we'll find out how you can add new tunes to your phone (if it's compatible). As we'll see, it's incredibly easy to find and add a song you like and load it up.

Ringtone Basics

If you've readHow Cell Phones Work, you know the central "brain" of a cell phone is a small微处理器. Just like the microprocessor in a computer, this unit controls everything that the cell phone does, working from information stored in the phone'smemory.

At its core, a ringtone is simply a computer program stored on the cell phone's memory chip. This program's sole purpose in life is to tell the microprocessor what the phone'sspeakersystem should do when the phone'sreceiverpicks up an incoming call.

Ringtone-capable phones already have a range of notes stored in memory (that is, they include information on speaker vibrationfrequenciesthat will produce particular tones). The ringtone program only has to tell the microprocessor which of these notes to play, in which order and at what speed. By adjusting these variables, the microprocessor can play an infinite number of ringtones.

The clearest example of this sort of programming language is theRinging Tone Text Transfer Language(RTTTL) format, developed by Nokia. Here's a typical section of RTTTL code, with a description of what eachbitmeans.

In order to enable a ringtone on your phone, you just have to get the appropriate program into the phone's memory. In the next section, we'll look at the different ways you can do this.

Getting a Tone

The first step in adding a ringtone to your phone is finding one that you like. Generally, this means checking out one of the dozens of ringtone sites on the Internet and picking a good one that's compatible with your phone model. Some sites charge for the use of their ringtones, to cover song royalties, among other things, and some sites provide tones for free. A lot of older songs (such as classical pieces) have been around long enough that their版权has expired -- they've entered the public domain, so they're free for anybody to use.

Once you've found a ringtone you like, you just have to get it into your phone's memory. There are a number of different ways to do this, depending on your particular phone model. The three major ways to add a new ringtone are:

Load the ringtone program into the phone from a computer, via a data cable.
Send the program to the phone over the airwaves.
Type the program into the phone directly, using the keypad.

Phones may use one particular method exclusively, but a lot of phones have multiple options. Check your instruction manual to find out what your phone can do.

If you have the right phone, software and computer configuration, loading ringtones through adata linkorinfraredinterface may be the simplest option, but it requires some work and expenditure to set everything up initially.

A more popular method is to send the new ringtone to your phone over theairwaves. This approach originated with Nokia, but other manufacturers have since added this capability to their phones. The basic idea is to send the phone a special sort oftext messagethat contains the program for the ringtone -- in most phones, this is done using eitherShort Message Service或增强Messaging Service technology.

Nokia originally developed Short Message Service to send short text messages between phones. Later, Nokia and Intel createdsmart messaging, a special protocol for sending functional, non-text information through SMS. Basically, a "smart" SMS message is coded to allow the equipped phone to recognize it as a graphic, ringtone, etc.

The most common method for transferring ringtones over the airwaves is to visit a ringtone Web site, pick out a tone, enter yourphone numberand let the site administrators send the message to your phone directly. Alternatively, you can use anSMS gateway siteto send a specific message to the phone yourself. This means finding the code for the ringtone you want, finding it in the appropriate format (Nokia binary format, for example) and copying it at as a smart message.

Cell phones with amelody composerlet you type in ringtones directly. The easiest way to use this feature is to find the appropriate "keypress sequence" for a tune on the Web. This sequence will tell you which buttons to press on your phone, in composer mode, to program the ringtone you want (check your instruction manual for details on your phone's composer mode). Of course, for the ringtone to work, the sequence has to be in the right format. Fortunately, you can find tons of sequences online for most phone models.

As cell phones evolve, ringtones will get more complex as well. Already, some phones are boastingpolyphonic ringtonecapability, meaning the phone can play more than one note at a time, allowing for richer, harmonized tunes. Some new phones let you record songs and voice messages for ringtones yourself. Many of these models also let you assign different ringtones to different incoming numbers, so you know who's calling you without even looking at your phone. Before long, ringtones will have graduated from an extraneous thrill to an essential phone feature.

For details on various ringtone formats, as well as hundreds of available ringtones online, check out the links on the next page.

Ringtone Basics

Getting a Tone

Lots More Information

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