Handsfree is an adjective describing equipment that can be used without the use of hands (for example via voice commands) or, in a wider sense, equipment which needs only limited use of hands, or for which the controls are positioned so that the hands are able to occupy themselves with another task (such as driving

Mobile phones and driving safety

Mobile phone use while driving is common, but dangerous. Due to the number of accidents that are related to cell phone use while driving, some jurisdictions have made the use of a cell phone while driving illegal. Others have enacted laws to ban handheld mobile phone use, but allow use of a...

) without needing to hunt far afield for the controls.

Devices that are typically used for handsfree communication use Bluetooth

Bluetooth

Bluetooth is a proprietary open wireless technology standard for exchanging data over short distances from fixed and mobile devices, creating personal area networks with high levels of security...

 as its wireless technology. They still require a mobile phone or other device to initiate a call. These devices include Bluetooth headsets, hands-free car kits (HFCK), and personal navigation devices (PND). Originally introduced as optional features connected by a wire to mobile phones or other communication devices, they now generally are available with wireless technology.

Bluetooth handsfree options are now also easily found in any high end automotive as part of the vehicle's stereo system, or in after market stereo system units. This option utilizes the vehicle's speakers to transmit the caller's voice in the phone call and have an embedded microphone in the stereo unit itself, the steering wheel, or use a separate wired microphone that can be placed anywhere in the vehicle.

Mobile phones

Handsfree mobile phone

Mobile phone

A mobile phone is a device which can make and receive telephone calls over a radio link whilst moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile network operator...

s are obligatory in many countries for use of a mobile phone while driving. However, studies have shown that even with a hands-free unit, the added distraction to the driver, and the increase in accident rates, are almost as substantial as when driving and talking on a normal mobile phone.

In the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

, as of 2003, it is illegal

Law

Law is a system of rules and guidelines which are enforced through social institutions to govern behavior, wherever possible. It shapes politics, economics and society in numerous ways and serves as a social mediator of relations between people. Contract law regulates everything from buying a bus...

 to use a handheld mobile phone while driving. Similar laws have been adopted in many jurisdictions worldwide, and many make provisions for hands-free phone use.

Installation of Hands Free devices in the UK is governed by MPT 1362, which is now referred to as FCS 1362. A technical document created and updated by the Federation of Communication Services.

In the USA, several states have banned talking on a hand-held cellphone while driving.

Software Technologies

Since handsfree devices replace a phone's own speaker

Loudspeaker

A loudspeaker is an electroacoustic transducer that produces sound in response to an electrical audio signal input. Non-electrical loudspeakers were developed as accessories to telephone systems, but electronic amplification by vacuum tube made loudspeakers more generally useful...

 and microphone

Microphone

A microphone is an acoustic-to-electric transducer or sensor that converts sound into an electrical signal. In 1877, Emile Berliner invented the first microphone used as a telephone voice transmitter...

 capability in a phone call, they now also must deal with the same issues that standard mobile phones and land phones deal with. The main acoustic issues are echo cancellation

Echo cancellation

'The term echo cancellation is used in telephony to describe the process of removing echo from a voice communication in order to improve voice quality on a telephone call...

and noise suppression, although there are others as well. There have been many ways developed to cancel echo in phone calls and results range from poor to excellent.

These acoustic technologies must also remove or reduce the noise levels so that the caller is well understood. A person making a call from a handsfree device who is in a busy restaurant or while driving will introduce large levels of noise into the call. This situation is complicated as the software must not only remove the noise around him, but must transmit his voice clearly and loudly to whoever is connected to him.

The best software solutions combine both echo cancellation and noise cancellation into a single technology so that the caller has the freedom to use a handsfree device anywhere they please. Having an acoustic solution with only one feature will dramatically reduce its flexibility.