Abstract: A logic analyzer having internal access to the test buses, clocks and events of a chip is used to debug the chip. The logic analyzer is designed with the capability to share existing memory in the chip during the debug process. Additionally, the configuration of the logic analyzer and observation of the acquired results in the shared memory can be accessed through normal control interfaces of the chip and does not require special test cards. The logic analyzer includes a clocking function, a trigger function, a signal multiplexer, and a memory block. The clocking function is configured to select as the sample clock for the function any of the clocks in the integrated circuit. In addition, the clocking function may provide a means to decimate these clocks by some factor to sample over larger intervals.

Abstract: Decoding LDPC (Low Density Parity Check) code with new operators based on min* operator. New approximate operators are provided that may be employed to assist in calculating one or a minimum value (or a maximum value) when decoding various coded signals. In the context of LDPC decoding that involves both bit node processing and check node processing, either of these new operators (i.e., the min† (min-dagger) operator or the min? (min-prime) operator) may be employed to perform the check node processing that involves updating the edge messages with respect to the check nodes. Either of these new operators, min† operator or min? operator, is shown herein to be a better approximate operator to the min** operator.

Abstract: In RF transceivers, a method and system for using phase shift key (PSK) sync word for fine tuning frequency adjustment are provided. One aspect of the invention provides for adjusting a local oscillator frequency in a radio frequency (RF) receiver when a residual DC offset remains after a coarse frequency offset adjustment if performed. The fine adjustment may be necessary because of the synchronization required with a PSK-based modulated portion of a Bluetooth packet. A residual phase shift detected in a sync sequence portion of the Bluetooth packet may be utilized to determine a residual or fine frequency adjustment. This approach may allow an RF receiver to operate, in some instances, without the need for an equalizer. In this regard, the power consumed by the RF receiver may be minimized and/or the overall cost of the RF receiver may be reduced.

Abstract: A system and method for hardware based reassembly of a fragmented packet is shown. The method includes receiving a bandwidth request to transfer a data packet from the data provider. Then, bandwidth is allocated to the data provider, where the allocated bandwidth is less than the requested bandwidth. Next, the present invention receives part of the data packet in the allocated bandwidth from the data provider, where the part of the data packet includes a fragment header, and the fragment header includes a sequence number for the part of the data packet. The part of the data packet is then stored in external memory. Finally, the data packet is reassembled by concatenating in the correct sequence the part of the data packet with other parts of the data packets to create the reassembled data packet.

Abstract: A system and method that produces a spatial average for interlaced video in a deinterlacer. The system detects edges in the video images and determines the angle at which the edges are oriented based on the gradient in the x-direction and the gradient in the y-direction. The direction of the edge is determined using the angle information of the edge. The system may also determine the strength of the edge. Based on the determined characteristics of the edge a filter may be selected to produce a spatial average of the edge in the image.

Abstract: Radio transceiver circuitry includes I/Q imbalance compensation logic within at least one of a digital modulator or a digital demodulator, depending upon whether the I/Q imbalance compensation block is compensating for I/Q imbalance in a transmit path or in a receive path. For a transmitter, a digital processor includes a baseband processor that produces transmit data (digital data) for transmission to a digital modulator that includes an I/Q imbalance compensation logic. The digital modulator, which may modulate in any known modulation scheme, produces in-phase and quadrature phase components that have been pre-compensated for I/Q imbalance that is introduced by downstream analog circuitry in the transmit path. In at least one embodiment of the invention, a “steepest descent” algorithm for finding optimal values of I/Q imbalance compensation parameters based upon a small number of image rejection measurements are used.

Abstract: Multi-carrier modulation fiber optic systems constructed using a series of electrical carriers, modulating the data on the electrical carriers and combining the carriers to form a wideband signal. The wideband signal can then be intensity modulated on a laser and coupled to a fiber optic channel. A receiver may then receive the laser signal from the fiber optic channel and convert it into an electrical signal. Multi-carrier modulation may be applied to existing fiber channels, which may be of lower quality. Existing fiber channels may have characteristics which prevent or restrict the transmission of data using intensity modulation at certain frequencies. An adaptive multi-carrier modulation transmitter may characterize an existing fiber optic channel and ascertain the overall characteristics of the channel. The transmitter and receiver can then be configured to use various bandwidths and various modulations in order to match the transfer characteristic of the fiber channel.

Abstract: An optical line terminal (OLT) monitors and controls communications with a plurality of optical nodes (ONs), such as optical network units (ONUs) and/or optical network terminators (ONTs), within a passive optical network (PON), such as, but not exclusively, an Ethernet-based passive optical node (EPON). A tagging mechanism is implemented to identify an origin ON that introduces a frame into the PON segment linking the origin ON with the OLT. The origin ON produces a PON tag to associate its identifier (ON_ID) to the frame. The PON tag facilitates filtering and forwarding operations, and enables the physical layer interface (PHY) to the PON segment to emulate a point-to-point and/or shared communications link. The PON tag allows a MAC control layer to create virtual ports to traffic incoming and outgoing optical signals, and supply the virtual ports to a forwarding entity for frame filtering and forwarding.

Abstract: A method of controlling a delay-locked loop (DLL) module is disclosed. The method includes the steps of receiving a clock signal, comparing the received clock signal with a reference clock signal to determine whether a required phase difference between the signals is within specified tolerances, producing a correction signal when the required phase difference between the received clock and reference clock signals is not within the specified tolerances, utilizing the correction signal to change a delay setting and forwarding the correction signal to slave DLL modules in communication with the DLL module. The comparing, producing, utilizing and forwarding steps are performed only after a period of time has elapsed from a prior incidence of the comparing, producing, utilizing and forwarding steps, where the period of time is sufficient to allow the DLL to settle and no extraneous results are produced.

Abstract: A method for accurate signal detection begins by receiving a radio frequency signal, which is then converted into baseband signals. The processing then continues by performing a normalized auto correlation on the down-converted baseband signal to produce a normalized auto correlation signal. The process continues by performing a periodic pattern detection on the down-converted baseband signal to produce a normalized detected periodic signal. The process then continues by comparing the normalized auto correlation value with an auto correlation threshold and by comparing the normalized detected periodic signal with a set of thresholds. When the normalized auto correlation value compares favorably with the auto correlation threshold and when the normalized detected periodic signal compares favorably with the set of thresholds, the down-converted baseband signal is indicated to be a valid signal.

Abstract: Described herein is a method and system for executing instructions. The system comprises a scalar unit for executing scalar instructions each defining a single value pair; a vector unit for executing vector instructions each defining multiple value pairs; and an instruction decoder for receiving a single stream of instructions including scalar instructions and vector instructions and operable to direct scalar instructions to the scalar unit and vector instructions to the vector unit. The vector unit can comprises a plurality of value processing units and a scalar result unit. The scalar unit can comprise a scalar register file. Communication between the vector unit and the scalar unit is enabled by allowing the vector unit to access the scalar register file and allowing the scalar unit to access output from the scalar result unit. The output of the scalar result unit may be based on the relative magnitudes of outputs from the plurality of value processing units.

Abstract: A system and method is presented for reuseing its S-CDMA related hardware (e.g., timestamp, minislot and frame count hardware) to create an extended mode to DOCSIS 2.0, namely to allow the TDMA channel to have any minislot size as is afforded to the S-CDMA channel. This reuse of existing S-CDMA hardware to create the extended mode is accomplished without the burden (e.g., complexity, cost, and schedule) of additional hardware to perform a separate set of calculations. In order to accomplish the foregoing, parameters are determined to use in a S-CDMA-type UCD message such that when that UCD message is interpreted by both the cable modem and CMTS hardware as though it were an S-CDMA message, the result is an TDMA minislot size that represents a desired integer number of ticks per minislot. In addition, the system and method periodically constructs the relationship between the system timestamp count, a channel's minislot count and the frame count via a timestamp snapshot.

Abstract: Embodiments include a system for performing dispersion compensation on an electromagnetic signal received over a communication channel, the electromagnetic signal bearing information at a symbol rate. An interleaved analog to digital converter (“ADC”) block may be used, wherein the interleaved ADC block may be configured to generate a plurality of digitally sampled signals from the electromagnetic signal. An interleaved equalizer block may be configured to digitally process each of the digitally sampled signals generated by the ADC block to generate a plurality of digitally equalized signals. A multiplexer may be configured to aggregate the digitally equalized signals into a composite output signal.

Abstract: A frequency-locked clock generator includes a voltage-controlled oscillator (VCO), a frequency-to-current converter, a reference current source and a gain stage. The VCO generates an output signal. The frequency-to-current converter generates a converter current proportional to a frequency of the output signal. The reference current source generates a reference current. The gain stage generates a control signal based on a difference between the converter current and the reference current. The control signal is applied to the VCO to adjust the frequency of the output signal. Feedback forces the VCO to generate an output clock signal such that the corresponding current it produces (i.e., the converter current) is equal to the reference current. When in lock, the frequency of the output signal is determined by a time constant (or equivalent time constant) of the frequency-locked clock generator.

Abstract: Embodiments include a decision feedback equalizer (DFE) that includes a first comparator configured to receive as inputs a soft value and a first threshold, a second comparator configured to receive as inputs the soft value and a second threshold, a selector configured to select an output of either the first comparator or the second comparator as a DFE output based on one or more previous bits output by the selector; an error calculator configured to determine an error for the first comparator and the second comparator, and a threshold adjuster configured to adjust the first threshold and the second threshold, the first threshold and the second threshold each being a non-linear combination of one or more previous outputs of the selector.

Abstract: A method for debugging a read only memory (ROM) in a wireless target device is disclosed. A wireless communication link is established between the target device and a host computer. A debug mode change command is received from the host computer by the application program running on the target device via a wireless communication interface in the target device. The wireless communication interface is parsed with the monitor program. A debug instruction is received by the monitor program from a debugger in the host computer where the debug instruction includes an entry address and a jump address. The application program jumps to the received jump address upon reaching the entry address location. An acknowledgement is transmitted from the target device to the debugger in the host computer, and, in response to the acknowledgement, a second debug instruction is received from the debugger in the host computer.

Abstract: A method of providing bias voltages for input output connections on low voltage integrated circuits. As integrated circuit voltages drop generally so does the external voltages that those circuits can handle. By placing input and output devices, in series, external voltages can be divided between the devices thereby reducing junction voltages seen by internal devices. By using external voltages as part of a biasing scheme for integrated circuit devices, stress created by the differential between external voltages and internal voltages can be minimized. Additionally device wells can be biased so that they are at a potential that is dependant on the external voltages seen by the low voltage integrated circuit.

Abstract: Methods and systems for operating a physical layer device (“PHY”) in an Ethernet network include methods and systems for detecting active link partners and for selecting a mode of operation based on detected active link partners. The PHY monitors fiber link media and copper link media for active link partners. The PHY selects a mode of operation according to detected active link partners. For example, a copper mode of operation is selected, preferably through logic circuitry, when an active copper link partner is detected and an active fiber link partner is not detected. Similarly, a fiber mode of operation is selected, preferably through logic circuitry, when an active fiber link partner is detected and an active copper link partner is not detected. The PHY interfaces with the active copper link partner when the copper mode of operation is selected. Similarly, the PHY interfaces with the active fiber link partner when the fiber mode of operation is selected.

Abstract: The variable gain amplifier includes a forward path that provides the amplifier variable gain, and a feedback path. The feedback path uses a switch that is turned on at low gain levels. The switch taps into the feedback resistor, shunting it to signal-ground and eliminating the feedback mechanism. This ensures that the input impedance seen at the input port does not grow excessively, using part of the feedback resistor as a passive termination at low gain levels. In this way variable gain ranges in excess of 30 dB can be achieved.

Abstract: A noise reduction circuit for reducing the effects of low frequency noise such as wind noise in communications applications is described. In one embodiment, the noise reduction circuit features a high pass filter formed by exploiting the existing off-chip AC coupling capacitances in making the connection to the source of audio signals. The filter may be adaptive to environmental low frequency noise level through programming the shunt resistances. A low-noise wide dynamic range programmable gain amplifier is also described. Adaptive equalization of the audio signal is also described through the utilization of programmable front-end resistors and a back-end audio equalizer.