Speaker Phones
Speaker Overview
The speaker phones are the phone with additional pair of microphone and speakers. Speaker phones have built in amplifier for amplifying the received voice signal and sending it to speaker. The speaker phones used batteries or a.c. adapter for providing additional functionality. The speaker phones are mostly used to allow multiple persons to participate in a conversation. The speaker function can be initiated with a press of button.
The speaker phone specifically designed for use by multiple persons has multiple microphones around their body so that it can pickup voice coming from any direction. This is very useful in cases such as conference rooms where multiple persons may be located around the speaker phone. These advanced speaker phones have special digital signal processing algorithms to differentiate between out the incoming sound and the sound in the room for echo cancellation. Some phone use noise canceling microphones to cut off the room background noise.
Many cordless phones too have the speaker phones function. The speaker phone may be in base unit of cordless phone or inside the handset.
Special speaker phones called chat phones are also available. They are basically IP phone and get connected to PC using USB cable to PC’s USB port. They have microphone as well as amplifier with speaker in the unit. They draw power from USB port of the device to which they are connected. These phones provide hands free communication using VoIP call facilities such as Skype. They have built-in circuits for acoustic Echo Cancellation, noise Cancellation and line Echo Cancellation.
The speaker phones are also available for harsh environment or rough usage. In the places prone to vandalism the exclusive use of speaker phone allows removal of handset and the cord with which it is attached to the phone. This avoids using cord for undesirable purposes such as suicides etc. The speaker phones are also used in environment where user’s hands are not free to hold the telephone handset.
