Abstract: A computer system having transceivers coupled to USB ports so as to provide a wireless USB bus between a computer and one or more peripheral devices is disclosed. The transceivers allows the computer to be remotely located from the peripheral devices (e.g., USB devices) by distances substantially greater than five (5) meters, and thus overcomes the five (5) meter limitation on cable length for a USB bus that burdened the conventional wired USB buses. The power utilization of the transceiver is also managed so as to comply with the USB specifications. In one embodiment, the transceivers are radio frequency (RF) transceivers.

Abstract: A wireless local area network (LAN) includes various devices, both hard-wired devices and wireless devices that allow communications between the devices and possibly to other devices in other networks, such as private computer networks and the Internet. The present invention allows wireless devices to sense and access various types of wireless networks, including IEEE 802.11a, 802.11b and 802.11g networks. Access to the wireless networks can be made with or without user intervention. The present invention provides an efficient and versatile means for wireless devices to communicate with other devices in a network.

Abstract: A digital modem for operating in a splitterless environment that supports fast retrain based on communication profiles. The modem includes a memory that stores a plurality of communication profiles, ADSL communication logic that sends and receives information via a phone line and that operates according to any one of the plurality of communication profiles, and signal quality monitor logic that continuously monitors communication on the phone line. The monitor logic provides a signal change indication if the signal quality changes by at least a predetermined amount. The modem further includes fast retrain logic that selects another one of the profiles stored in the memory in response to the signal change indication, that retrains the communication logic to operate according to the selected profile and that cooperates with the communication logic to transmit a fast retrain indication via the phone line to the central office ADSL modem.

Abstract: A multipoint digital simultaneous voice and data (DSVD) conferencing system includes a plurality of local DSVD modems to communicate with a plurality of remote DSVD modems and a bridge to transfer data and digitized voice signals among the plurality of remote DSVD modems by way of the plurality of local DSVD modems. A plurality of simultaneous conferencing connections are maintained between the plurality of local DSVD modems and the plurality of remote DSVD modems. The system support a multipoint DSVD conferencing session connecting the plurality of remote DSVD modems.

Abstract: Rapid identification and modeling of transmission media channel characteristics of a communications system using a correlation based technique. The technique provides a known training sequence used to generate a known quantity that operates on an observed or measured received signal, which is a function of the training sequence and the channel's impulse response, to give an estimate of the model of the channel. The technique decouples the training sequence from the observed or measured output, leaving the estimated impulse response. The impulse response of the transmission media channel is rapidly computed and processed to set the initial values of filter coefficients, for example, an echo canceller and an equalizer, in the communications system. Once the coefficients are initialized, if needed, a standard technique, such as least mean square (LMS) correlation, can be used to fine-tune the coefficients to converge on or model the transmission media channel's characteristics.

Abstract: A peripheral coder/decoder (codec) that has low power consumption such that the peripheral codec facilitates bus-powered peripheral devices that utilize a codec. One such peripheral device is a modem. In the case of host-based modem, a host computer provides processing capabilities while a bus-powered peripheral device contains circuitry for analog-to-digital and digital-to-analog conversions as well as circuitry for interfacing to a transmission media. The bus-powered peripheral device is coupled to the host computer by a peripheral bus. In one embodiment, the peripheral bus is a Universal Serial Bus (USB) bus and the bus-powered peripheral device is a USB device. By being bus-powered, the bus-powered peripheral device does not require its own separate power source. A method for transmitting data over the peripheral bus using the host-based modem and the bus-powered peripheral device are also disclosed.

Abstract: A digital modem for operating in a splitterless environment that supports fast retrain based on communication profiles. The modem includes a memory that stores a plurality of communication profiles, ADSL communication logic that sends and receives information via a phone line and that operates according to any one of the plurality of communication profiles, and signal quality monitor logic that continuously monitors communication on the phone line. The monitor logic provides a signal change indication if the signal quality changes by at least a predetermined amount. The modem further includes fast retrain logic that selects another one of the profiles stored in the memory in response to the signal change indication, that retrains the communication logic to operate according to the selected profile and that cooperates with the communication logic to transmit a fast retrain indication via the phone line to the central office ADSL modem.

Abstract: A digital modem for operating in a splitterless environment that supports fast retrain based on communication profiles. The modem includes a memory that stores a plurality of communication profiles, ADSL communication logic that sends and receives information via a phone line and that operates according to any one of the plurality of communication profiles, and signal quality monitor logic that continuously monitors communication on the phone line. The monitor logic provides a signal change indication if the signal quality changes by at least a predetermined amount. The modem further includes fast retrain logic that selects another one of the profiles stored in the memory in response to the signal change indication, that retrains the communication logic to operate according to the selected profile and that cooperates with the communication logic to transmit a fast retrain indication via the phone line to the central office ADSL modem.

Abstract: A multipoint digital simultaneous voice and data (DSVD) conferencing system includes a plurality of local DSVD modems to communicate with a plurality of remote DSVD modems and a bridge to transfer data and digitized voice signals among the plurality of remote DSVD modems by way of the plurality of local DSVD modems. A plurality of simultaneous conferencing connections are maintained between the plurality of local DSVD modems and the plurality of remote DSVD modems. The system support a multipoint DSVD conferencing session connecting the plurality of remote DSVD modems.

Abstract: A multipoint conferencing system communicates with a first remote digital simultaneous voice and data (DSVD) modem and a second DSVD modem. The multipoint conferencing system has a first DSVD modem adapted to communicate with the first remote DSVD modem and a second DSVD modem adapted to communicate with the second remote DSVD modem. Each DSVD modem has an analog to digital converter and a digital signal processor coupled to the analog to digital converter for receiving data from the remote DSVD modems. The system also has a bridge coupled to the first and second DSVD modems for transferring data between the first and second remote DSVD modems.

Abstract: A signal processing apparatus for processing data digital signals is disclosed. The signal processing apparatus includes a high-efficiency power switching amplifier that optimizes processing during low-power applications. A signal equalizer is further coupled to the power switching amplifier and has a plurality of signal bands for defining equalization characteristic desired for the signal processing system. A gain control unit is coupled to the signal equalizer for adjusting gain of the equalized input signal handled by the signal equalizer. Lastly, a digital amplitude compressor is coupled to the gain controller and the power switching amplifier and is programmable so as to compress only those signals having an amplitude greater than a first threshold level without compressing those signals that fall below that first threshold level. Typically, low-power applications cover wattage ranging from two to seven watts of power.