Abstract: The present invention is directed to a system and method for communicating in a point to multipoint DSL communication network. Preferably, the point to multipoint communication network is established in the environment of a home or small office, and the invention is realized through a computer that may dynamically establish both LAN and WAN communications. Broadly, the system and method are realized by a computer that is configured to assume a role as either a Master or a Slave on a LAN. If the computer is the first (or only) computer powered up on the LAN, then it assumes the role of Master. In this role, the computer establishes a communication link with a WAN (such as with an Internet Service Provider), and directs all WAN communications over the WAN, using a WAN frequency and protocol (such as DSL). As other computers join the LAN, then WAN communications from those computers are relayed through the Master to the WAN. These communications are relayed to the Master using a LAN frequency band.

Abstract: An improved analog front end and methods for increasing the power efficiency of duplex signals on a transmission line are disclosed. The improved analog front end bifurcates a hybrid into a fixed portion and an adaptive portion. The adaptive portion combines a biquad and a summer to produce a filter transfer function suited to compensate for transmission line irregularities. A method for configuring a local transceiver to minimize power requirements at a remote transmitter is disclosed. Broadly the method entails, applying a transmit signal to a front end in the absence of a remote signal; optimizing the transmit signal power; recording the reflected transmit signal; applying an adaptive filter in response to transmission line irregularities; and controllably adjusting the adaptive filter to minimize the amplitude of the reflected version of the transmit signal in the receive path. A method for recovering a remotely generated signal is also disclosed.

Abstract: A method and apparatus are disclosed for reducing crosstalk in a telecommunication system. Broadly, the present invention utilizes a common mode signal to obtain additional information that can be used to better approximate the transmitted signal (by approximating and canceling crosstalk or otherwise). In accordance with one embodiment of the invention, a modem is provided having improved crosstalk cancellation circuitry for canceling crosstalk received on a local loop (or otherwise estimating the remotely transmitted signal) carrying modem communications. The modem includes a first input for receiving a signal carried on the local loop and a second input for receiving a signal obtained from the common mode. The modem further includes processing circuitry configured to either reduce crosstalk present in the signal carried on the local loop, or to otherwise closely approximate the remotely transmitted signal.

Abstract: A memory optimized system and method for data interleaving/de-interleaving are disclosed. A data interleaver/de-interleaver may be implemented with a memory device and an improved data interleaver/de-interleaver. The improved data interleaver/de-interleaver may be implemented with a controller, a first array, and a second array. The first array identifies a maximum depth value for each of a plurality of memory segments responsive to both a block data length and the desired interleaving/de-interleaving depth. The second array comprises an index associated with each of the plurality of memory segments that may be used to derive write and read addresses.

Abstract: An improved ADSL modem is presented. The ADSL modem in cooperation with a remote ADSL modem will exchange manufacturer identification information during initial DSL system training to establish a DSL communication link. The improved ADSL modem may comprise a memory device containing system parameters and operational algorithms previously determined to maximize DSL link performance between ADSL modems manufactured by different vendors. The improved ADSL modem is well suited for central office applications as it provides a solution for optimizing system performance that is transparent to remotely located ADSL modems. An ADSL modem in accordance with the present invention may comprise a digital signal processor and a memory device configured to store appropriate system parameters and operational algorithms that provide an optimized DSL communication link once applied during system initialization. The present invention also provides a method for optimizing DSL system performance.

Abstract: The present invention is generally directed to a system and method for encoding a DSL information bit stream and decoding a corresponding encoded DSL symbol. In accordance with one embodiment, an apparatus for encoding a DSL information bit stream is provided having a switch with an input configured to receive a DSL information bit stream and at least two outputs. An encoder is provided and coupled to a first output of the switch. A serial to parallel converter is provided and coupled to both an output of the encoder and a second output of the switch. Finally, a mapper is provided and coupled to an output of the serial to parallel converter through multiple paths. Preferably, a first coupling path between the serial to parallel converter and the mapper is a direct path and a second coupling path includes a second encoder.

Abstract: A demapping system and method for demapping symbols into bits, is provided. An embodiment of the system comprises a processor, and a memory that is coupled to the processor. The memory comprises a memory module that comprises a program that finds a hard demapper output d based on a received symbol r; finds a challenger ci for each i, the challenger ci is a challenger of the hard demapper output d, i is an integer whose maximum value is a number of bits of the challenger ci; calculates reliability mi for each i, the reliability mi is the reliability of the hard demapper output d; and calculates soft bit xi for each i, the soft bit xi is calculated based on the reliability mi.

Abstract: A system and method for providing adaptive rate selection mitigates impulse-like noise and allows for interleaving and RS coding, while not excessively delaying data transmission. Generally, the system utilizes a memory and a processor, wherein the processor is programmed by software stored within the memory to perform the step of reading a specified data transmission delay rate for a channel utilized for data transmission. A Reed Solomon encoder is utilized by the adaptive rate system, which performs the steps of: reading a specified number of redundant bytes in a Reed Solomon frame; determining a level of impulse protection control from the number of redundant bytes in the Reed Solomon frame and a maximum code word length; and determining a number of symbols comprised within the Reed Solomon frame. In addition, an interlever is utilized for determining an interlever depth via use of said number of symbols comprised within the Reed Solomon frame and the specified data transmission delay rate for the channel.

Abstract: Disclosed herein are exemplary techniques for initiating a direct wireless link between two wireless devices. The method includes transmitting, a first frame from a first wireless device having a destination media access control (MAC) address; receiving, at the first wireless device, a second frame from a second wireless device, the second frame having a destination MAC address and being intended for a wireless device other than the first wireless device; and establishing a direct wireless link between the first wireless device and the second wireless device when the when the destination MAC address of the first frame matches the destination MAC address of the second frame.

Abstract: Disclosed herein are exemplary techniques for initiating a direct wireless link between two wireless devices.

Abstract: An analog front end system comprising a digital-to-analog converter, a line driver, a multiple-input device, and an analog-to-digital converter is presented. Furthermore, a method for DSL line testing comprising the steps of providing test stimuli to and receiving responses from a DSL line using an analog front end is presented. The presented system and method provides for the testing of a DSL line in an xDSL communications system deployment.

Abstract: Disclosed herein are exemplary techniques for establishing a direct link independent of an access point and for identifying proximate wireless stations users. The method and method are provided in a wireless network with an access point logically connected to at least a first wireless device and a second wireless device to notify the first wireless device that the second wireless device is in proximity to said first device. The system and method also establish a direct wireless link between a first wireless device and at least one proximate wireless device by identifying a second wireless device within a predetermined proximity of the first wireless device, determining an identity associated with a user of the second wireless device, comparing the identify with a set identities, and notifying the user of a proximity of the user of the second wireless device based on the comparison.

Abstract: A system and method for a filter tuner is presented. The system comprises a sequential logic, a register, a comparator, a first and second counter, a synchronizing logic, a first and second oscillator, a control logic, and a first and second combinational logic. The method comprises the steps of executing a calibration cycle of a filter tuner, executing a measurement cycle of the filter tuner, and tuning a filter with the filter tuner dependent on a determined cutoff frequency variation.

Abstract: A system and method for providing cancellation of interference in a repeater configuration is disclosed, wherein the repeater is located between a first endpoint and a second endpoint. A data signal received from the first end point is amplified in accordance with an amount of power required to drive the data signal to the second endpoint. Local echo introduced by the repeater is then removed from the amplified data signal. Coupled signals introduced by the repeater are then removed after which the data signal is transmitted to the second endpoint.

Abstract: The present invention relates to an algorithm for ensuring compliancy of an algorithm module when integrated in a real time software system. The compliancy tests may include a memory test, interrupt test, latency test and other tests, as well as combinations thereof. An inventive aspect of the present invention relates to a unit test harness for verifying that a software algorithm module meets performance and functional requirements when integrated in a complete real-time software system. A software algorithm module eliminates or reduces unwanted behavior by the caller or other software on a real-time software system due to incorrect operations, which may involve interrupts, memory usage, register usage and/or other factors.

Abstract: A system and method for performing a general ternary branch instruction is provided. Additionally, different approaches are provided for reducing the complexity of a ternary branch instruction word and corresponding hardware.

Abstract: A radar detector (10) includes a first period detector (76, 122), a second period detector (96, 120) and a third period detector (86, 124) within a multi-period periodicity validator 38. The first period detector (76, 122) detects radar pulses exhibiting one-half of an expected pulse period (48), the second period detector (96, 120) detects radar pulses exhibiting the expected pulse period (48), and the third period detector (86, 124) detects radar pulses exhibiting twice the expected pulse period (48). A plurality of pulse-train records (40) can simultaneously track a plurality of possible pulse trains. A control element (84, 136, 138) accounts for missing pulses and corrects the expected pulse period when missing pulses have caused the expected pulse period to be inaccurate.

Abstract: Systems and methods for increasing data capacity in communication systems is presented. In one embodiment, line characteristics are determined, and a downstream bandwidth is adaptively allocated in response to the determined line characteristics. In this regard, the upstream and downstream bandwidths may be seen as adaptively changing as a function of line characteristics.

Abstract: A system and method for reducing transmit carrier wander in a DSL communication system are disclosed. A network timing reference unit provides an automatic embedded solution for synchronizing DSL frames to an external communication system reference clock. The network timing reference unit applies or removes bits to adjust the length of a DSL frame in response to a sliding window state table. A sliding window is selected in response to the relative position of the DSL frame to a system clock reference point over a number of DSL frames. A network timing reference unit in accordance with the present invention may comprise a counter, a network timing latch, a synchronization word detector, a DSL frame latch, a lead/lag comparator, a sliding window buffer, a sliding window state table, a DSL frame state recorder, and a sensitivity buffer. The present invention provides a method for reducing transmit carrier wander in a DSL transceiver.

Abstract: A radar detector (10) includes a first period detector (76, 122), a second period detector (96, 120) and a third period detector (86, 124) within a multi-period periodicity validator 38. The first period detector (76, 122) detects radar pulses exhibiting one-half of an expected pulse period (48), the second period detector (96, 120) detects radar pulses exhibiting the expected pulse period (48), and the third period detector (86, 124) detects radar pulses exhibiting twice the expected pulse period (48). A plurality of pulse-train records (40) can simultaneously track a plurality of possible pulse trains. A control element (84, 136, 138) accounts for missing pulses and corrects the expected pulse period when missing pulses have caused the expected pulse period to be inaccurate.