Digital Phones Use Microphones
Just like their analog cousins, digital phones must convert sound into electrical signals before they can perform their telecommunication purpose. This conversion is accomplished by use of a microphone, a thin membrane that picks up vibrations in the air (caused by voices or other sound) and converts those vibrations to electrical signals. These signals are then fed to the phone's processor for digital conversion.
Digital Phones Use Data Packets
While an analog telephone simply accepts the electrical signals from the microphone and sends them out to the telephone network, a digital phone first converts the electrical signals to data packets using a microprocessor. The data packet format is proprietary to the telephone manufacturer, but most vendors convert data into 8-bit packets of ones and zeros (binary packets) suitable for transmission over the Internet. Because these packets are compliant with standards for Internet Protocol, they are known as IP packets.
Digital Phones Work With A Server
Because traditional telephones work directly with electrical signals and digital phones work with data packets, a computer known as a "gateway" serves as an interface between the digital phone and the analogue telephone network. The gateway converts digital packets to analog electrical signals for outgoing communication, and converts incoming electrical impulses into digital data packets. In call center environments or other uses where a large number of digital phones are located in close proximity, the gateway server may be located in the center itself. In residential Voice Over Internet Protocol (VOIP) uses, digital phones may connect to a server in another city, state, or even country.
Digital Phones Also Decode Incoming Signals
Just as digital phones encode sounds into data packets and send them out to a server, they also use their microprocessors to decode (or, as technophiles refer to the process, demodulate) incoming data packets back into electrical signals. These signals are sent to a small speaker in the phone's handset or speaker-phone component where the speaker causes vibrations in the air that are received by the ear as sound.
Tags: electrical signals, data packets, digital phones, digital phone, Digital Phones