1800 results about "Interference immunity" patented technology

A data transceiver module for digital data communications in a portable handheld 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.