WaveLan

WaveLan is a copyright of Lucent, and is their name of the wireless ethernet product line that was first an NCR product and then and AT&T product. It is also known as the DEC RoamAbout.

This page was written before the current 802.11 specification was created. Since that time, Lucent has discontinued the older, proprietary gear refered to in this page. Unfortunately, they continued to use the name Wavelan on their 802.11 gear for a time. They then renamed their 802.11 equipment Orinoco, and finally renamed the whole division of the company Avaya. Personally, I find this name game annoying and confusing, but it seems to be very popular with corporate giants these days.

The WaveLan comes in ISA, MCA, PCI, and PCMCIA versions. They operate on two bands: 915 Mhz and 2400 Mhz, using Direct Sequence Spread Spectrum (DSSS).

Spread Spectrum is a relatively new and somewhat complex radio technology that involves spreading the signal out of a wide portion of bandwidth, the original signal is mixed with a larger pseudo-random sequence. The receiving end strips away the pseudo-random sequence and "votes" on the results, majority winning for that bit. The result is a modulation method quite impervious to interference, either natural or man-made.

The WaveLan operates at 1.5 MBPS, half-duplex, in a carrier-sense multiple-access environment. It is license free, operating under the FCC Part 15 rules limiting power output and antenna height for such devices. Typically, a small "rubber duck" antenna is attached to the back of the device. However, with a decent antenna, such as a 10 element beam antenna, extending its range far beyond the 800 ft. it normally has. It has been used as an internet backbone in Latvia. Distances over over 6 KM have been achieved, using high-gain antennas, and with direct line-of-site orientation.

Problems with the WaveLan: