A data
transceiver module for
digital data communications in a portable hand-held
data terminal has multiple data
spread spectrum modes which include direct sequence and
frequency function modulation algorithms. The
transceiver module has multiple user or program configurable data rates, modulation, channelization and
process gain in order to maximize the performance of radio data transmissions and to maximize
interference immunity. Various module housings, which may be PCMCIA type, are able to be mated with a suitably designed
data terminal.
Media access control protocols and interfaces of multiple nominal operational frequencies are utilized.
Wireless access devices in a
cell based network each consider a variety of factors when choosing one of a plurality of
modes of
wireless operation and associated operating parameters. Such selection defines a
communication channel to support
wireless data, message and communication exchanges. In further embodiments, the
wireless access devices also support a second channel, a busy /
control channel, for managing communication on the main
communication channel and to overcome
roaming and hidden terminal problems.
Roaming terminal devices are also configured to support the dual channel design. Such configuration in both circumstances may involve the use of a multimode radio that is timeshared between the two channels or two radios, one dedicated to each channel.