Q: Who offers wireless communications equipment (other than Telxon) in the 900-MHz to 2.4-GHz range? We plan to use the equipment for warehousing, retailing and building-to-building communications.
Greg Hight
Fiber Optic Technologies (foti)
Denver, CO
A: I went surfing on the Internet using the key words "GHz", "MHz", "cordless" and "telephone" and found the following sites (and no doubt there are others):
- Toshiba--http://www.toshiba.com/ taipress/toshibei.htm
- U.S. Robotics--http://www.usr.com/ home /20413.08.html
- V-tech--http://www.vtechphones. com
- Uniden--http://www.aherncorp.com/ uniden/
- AT&T--http://www.att.com/phonecenter/cordless/900coscr.html
- Distributor for Sony--http://www. hubber.com/products/phones/900.htm
- Distributor for Samsung, Uniden and Panasonic -- http://www.electroweb.com/product/elect.htm
The cordless telephone has become the primary telephone instrument for many users and, in my opinion, this popularity has brought increased channel crowding and interference. The shorter wavelength at 900 MHz allows digitized voice signals to pass through walls, trees, bushes and other physical barriers more easily than cordless telephones operating at 46 to 49 MHz, resulting in clearer reception. The digital encoding of voice signals also lessens the likelihood that conversations will be picked up by other cordless telephones, two-way radios or scanners. Spread-spectrum technology distributes the voice signals (and radio energy) from a call over a broad area within the available frequency band, instead of concentrating them on a single channel. This minimizes the chance of interference and enhances the privacy of communications.
Because users continue to demand more features, we will continue to see improvements in cordless telephones, which will provide enhanced performance and clarity, and more freedom of movement for users. A word of caution: Do not assume you have complete privacy. Although it is a violation of federal law to eavesdrop on cordless telephone conversations, that may not be enough to deter inquiring minds.
Donna Ballast is a communications analyst at the University of Texas at Austin and a Bicsi registered communications distribution designer (Rcdd). Questions can be sent to her at Cabling Installation & Maintenance or at PO Drawer 7580, University of Texas, Austin, TX 78713; tel: (512) 471-0112, fax: (512) 471-8883, e-mail: [email protected].