Cued Speech for Young and Not So Young

As printed in Hearing Health, volume 21:1, Spring 2005

By Gora Ganguli, M.B.A.

From satellite communications to cell phones, to keyless entry in cars, wireless is rapidly becoming the most profound technology of our age. However, unlike other prominent new developments such as plasma-screen televisions and iPODs, wireless is a background technology. It is a basic fabric for how electronic devices work together and, by freeing us from cables and wires, it is changing the way we use these devices. Try to imagine for a moment the television-viewing experience without that ubiquitous wireless device which we all take for granted — the remote control. Whether we notice it or not, wireless technology is everywhere and is changing the way we live, work and play.

There are several types of wireless technologies in use today, including infra-red (IR) and radio frequency (RF). Remote controls for televisions and stereos, for example, use IR technology to communicate information. One of the drawbacks of IR is that it requires the sending and receiving devices to be in line of sight of each other for communication to take place. RF is more practical and is becoming more widely used as it can transport more information over longer distances and pass through solid objects. It also uses more diffuse waves and does not require that devices be in line of sight in order to communicate. Cellular phones use RF wireless technology to link individual phones to towers or base stations scattered throughout urban and rural areas.

Laptop computers now come equipped with the capability to connect to wireless local area networks found in offices and other places such as hotels and airports, enabling us to surf the Internet or connect to our office e-mail systems while roaming freely. Many people today install wireless networks in their homes, very economically, to link multiple computers from different rooms in the house to a single Internet connection and to devices like printers and scanners.

One of the big challenges with wireless technology has been the issue of standards or compatibility. Even though we’re making progress, there are still a number of different standards for cell phones and they are not interoperable. A GSM (Global System for Mobile Communications) phone, for instance, will not work in a CDMA (Code Division Multiple Access) network and, as these standards also vary from country to country, cell phones are not always useful for international travelers. Even television remotes, garage-door openers and keyless car-entry systems are usually not compatible with products from different manufacturers. For wireless to be truly useful, as well as economical, interoperability of the sort we have with telephone land lines is a must.

In 1994, Swedish telecommunications giant, Ericsson, proposed Bluetooth as a standard for wireless connectivity. Getting the world’s electronic product manufacturers to agree on a standard was no easy feat, and even more difficult was developing a communications protocol that would actually work. In 1998, Nokia, IBM, Toshiba and Intel joined Ericsson to form the Bluetooth Special Interest Group to add muscle to the initiative, and now, seven years later, Bluetooth is firmly entrenched in the world of wireless.

Bluetooth is a short-range technology to quickly and efficiently connect devices within 10 meters of each other. It eliminates the cables and wires that connect devices which exchange data, voice or audio. A keyboard or mouse connected to a computer, earphones or headset connected to a cell phone and a digital camera connected to a printer are everyday examples of Bluetooth uses. These devices have to be Bluetooth-enabled, which is done by a special radio chip. The software contained in the chip allows the two devices to “shake hands” with each other and then communicate freely, a process called “pairing.” Once paired, devices look for each other when they are in range.

Bluetooth works in the electro-magnetically “noisy” 2.4 GHz frequency bands, as do most cell phones. To ensure that clear, noise-free exchange is possible, it uses a fast, frequency-hopping technique. Signals hop 1600 times per second between frequencies and correct errors to ensure that information is not corrupted. Additionally, unlike traditional cell phones, frequency hopping and encryption keep Bluetooth conversations from being easy eavesdropping targets. Paired devices can also communicate with each other without interfering with other nearby Bluetooth devices. All of this works at about one one-hundredth of the power level of a cell phone, so smaller batteries can be used.

Bluetooth and Amplified Hearing
Bluetooth is great for anyone with high-tech gadgets and especially for those who wear hearing instruments. Though we are yet to comprehend all the ways Bluetooth can positively impact hearing technology, one immediate use will be in special cell-phone headsets for hearing aid users.

Cell phones are so integrated into our daily lives and hearing aid users need them as

much as anyone else. However, the electromagnetic interference (EMI) generated by the proximity of a cell phone and a hearing aid makes the combination of the two a challenge. While research and development continue to improve this, no robust solution is yet available. Bluetooth-enabled headsets will permit the reception of EMI-free cell-phone signals with the added benefit of hands-free driving, typing or other manual activities.

Headsets in general are being used more often to comply with new laws prohibiting cell-phone use in cars and their prevalence could change some societal perceptions about head gear. In 2004, almost 15 million Bluetooth cell-phone headsets were sold around the world and industry experts are forecasting sales surpassing 100 million by 2008. Very soon hearing aids could converge with headsets and yield multi-functional communication devices. The technology already exists and such Bluetooth-based multi-functional communication devices are already appearing on the market. Once a Bluetooth-enabled communication device is on the ear, connecting it to other useful Bluetooth devices is natural. Direct audio feed from the television, stereo or portable music player, personal computer, cell phone and even a land-line phone is already possible.

One of the many advantages of standard technology and interoperability is that the cost of implementing new applications is usually low. This is true for Bluetooth applications and could enable electronics manufacturers to embed Bluetooth into just about anything without significantly increasing product cost. And they are beginning to do exactly that.

Even televisions, audio players and phones that don’t have built-in Bluetooth can be updated with inexpensive, add-on Bluetooth transceivers (transmitter/receiver) called “dongles.” Plus, multiple-pairing capability already available with Bluetooth will enable us to switch between the connections of different devices. We will be able to watch television with direct audio feed and then, with a touch of the headset, answer calls from our cell phone or our home phone without having to physically handle these devices.

Futuristic as it might sound, it is already happening. Who would have believed even 15 years ago that just about everyone today would own cellular telephones? Wireless technology holds the promise of transforming hearing aids into multi-functional communication devices, turning hearing loss into hearing gain.

Learn more about Bluetooth and current Bluetooth products at www.bluetooth.com and www.gennum.com. 

Gora Ganguli is a senior vice president of Gennum Corporation and is the general manager of their Audio & Wireless Products Division. He is the secretary/treasurer and a director of both the Hearing Industry Association and the Better Hearing Institute. An engineer and M.B.A. by training and a lifelong amateur musician, he strives to ensure that his children take better care of their hearing health than he did.

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