Ricochet is the only wireless packet data network today that
was built from the ground up to handle high speed data, up to
128 Kbps. Modems are available from third-party sources that
allow connection to laptop computers by at least one Pocket
PC. The network has about 41,000 customers in 15 markets as
of July 2001 but the parent company, Metricom, has filed for
Chapter 11 in bankruptcy court, so anything could happen to
Ricochet. On August 8, 2001, Metricom ceased operations of
Ricochet but the company is negotiating with third parties to
buy the Ricochet network. If a third party can buy the network
at a really good price, then Ricochet may continue in some
form. As of the publishing of this book, the outcome is
unknown. The high costs of building out a nationwide network
far exceeded the revenue, and current economic conditions
make financing very difficult.
The Ricochet radio network utilizes several elements
including microcell radios and wired access points. This provides
true Wireless Internet access to information—regardless
of where it resides either on the Web or the intranet, in an
email message or a video clip.
In many ways the Ricochet network functions similarly to a
wireless Ethernet network. Acquisition is a necessary first step
for each radio on the network. The user radio, when first turned
on, must locate neighboring radios and Ricochet modems by
sending out synchronization packets. On acknowledgment from
neighboring radios, it must then get the authorization from the
name server. Only then does it join the network.
The network operates in two Industrial, Scientific, Medical
(ISM) bands of regulated, unlicensed spectrum, the 900 MHz
band and the 2.4 GHz band, in addition to the licensed 2.3
GHz Wireless Communications Systems (WCS) spectrum. The
physical layer uses Frequency Hopping Spread Spectrum
(FHSS) technology.