Abstract: An architecture to extend a wired controller area network (CAN) to the wireless domain of a low rate wireless personal area network (PAN) network is described herein. Such architecture provides a low cost, low power, efficient, and secure wireless network interface compatible with many existing SCADA infrastructure networks, in addition to countless other installations incorporating a CAN backbone. An architectural model for such an extension module includes additions to the CAN protocol stack. New protocols for the tunneling of messages and for enhancing reliability are also described.

Abstract: An architecture to extend a wired controller area network (CAN) to the wireless domain of a low rate wireless personal area network (PAN) network is described herein. Such architecture provides a low cost, low power, efficient, and secure wireless network interface compatible with many existing SCADA infrastructure networks, in addition to countless other installations incorporating a CAN backbone. An architectural model for such an extension module includes additions to the CAN protocol stack. New protocols for the tunneling of messages and for enhancing reliability are also described.

Abstract: An audio automatic gain control (AGC) circuit (301) employs a method (400, 500) and apparatus (300) for mitigating noise in an output signal (307) of the audio AGC circuit (301). The audio AGC circuit (301) or a circuit coupled to the audio AGC circuit, such as a speech encoder (302), determines (405) whether audio information is present in an input signal (137) to the audio AGC circuit (301). When audio information is not present, the audio AGC circuit (301) applies (411) a gain to the input signal (137) that is less than a current gain being applied, thereby mitigating noise in the audio AGC circuits output signal (220) when audio is not present.

Abstract: An uncorrectable set of input vectors (303), comprising a primary input vector (P) and a secondary set of input vectors (S), is provided at a sender (301). The secondary set of input vectors is error correction encoded and modulated with a predetermined input vector (PIV) to produce a secondary set of modulated vectors (S'). A predetermined codeword (PC) is sent along with the secondary set of modulated vectors to a target (302). At the target, the predetermined codeword is decoded and the resulting decoded predetermined codeword 306 is used to demodulate the secondary set of modulated vectors. As the predetermined codeword is chosen such that, when decoded, it is not identical to the predetermined input vector, the secondary set of demodulated vectors (S") will contain a sufficient number of errors to indicate to the target that the set of input vectors is uncorrectable.