Patent classifications
H03D1/04
FILTER CIRCUIT
A filter circuit may include a first path having a first complex baseband filter. The circuit may further include a second path having a second complex baseband filter. The circuit may further include a combiner coupled to an output of the first complex baseband filter and an output of the second complex baseband filter.
Circuits for efficient detection of vector signaling codes for chip-to-chip communication
In a detection circuit, inputs correspond to received indications of vector signaling code words received by a first integrated circuit from a second integrated circuit. With four inputs, the circuit compares a first pair to obtain a first difference result and compares a second pair, disjoint from the first pair, to obtain a second difference result. The first and second difference results are then summed to form an output function. A system might use a plurality of such detection circuits to arrive at an input word. The circuit can include amplification, equalization, and input selection with efficient code word detection. The vector signaling code can be a Hadamard matrix code encoding for three input bits. The circuit might also have frequency-dependent gain, a selection function that directs one of the summation function result or the first difference result to the output function, variable gain, and/or a slicer.
Apparatus and methods for inducing electromagnetic waves on a cable
Aspects of the subject disclosure may include, receiving a communication signal, and generating an electromagnetic wave that propagates along an outer surface of a dielectric layer environmentally formed on a cable. The dielectric layer can be a liquid disposed on an outer surface of the cable that enables the electromagnetic wave to propagate along the dielectric layer of the cable without an electrical return path, and conveys the communication signal. Other embodiments are disclosed.
Apparatus for transmitting broadcast signals, apparatus for receiving broadcast signals, method for transmitting broadcast signals and method for receiving broadcast signals
A method and an apparatus for receiving broadcast signals thereof are disclosed. The apparatus for receiving broadcast signals, the apparatus comprises a receiver to receive the broadcast signals, a demodulator to demodulate the received broadcast signals by an OFDM (Orthogonal Frequency Division Multiplex) scheme, a frame parser to parse a signal frame from the demodulated broadcast signals, wherein the signal frame includes service data corresponding to each of a plurality of physical paths, a time deinterleaver to time deinterleave service data in each physical path by a TI (Time Interleaving) block, wherein the time deinterleaver further performs inserting at least one virtual FEC block into at least one TI block of the service data, wherein each TI block includes a variable number of FEC blocks of the service data, wherein a number of the at least one virtual FEC block is defined based on a maximum number of FEC blocks of a TI block and a decoder to decode the time deinterleaved service data.
Peak to average power ratio reduction in multichannel digital front-ends (DFES)
Systems and methods are provided for peak to average power ratio (PAPR) reduction in multichannel digital front-ends (DFEs). A transmitter may be configured to reduce PAPR during multichannel transmission, with the reducing comprising: generating a plurality of frequency-domain symbols, each of which corresponding to a particular one of a plurality of subcarriers; assigning the subcarriers to a plurality of channels, wherein a number of channels is less than a number of subcarriers; and generating a plurality of time-domain signals corresponding to the channels. An adjustment to reduce PAPR may be applied to at least one of the time-domain signals, with the adjustment being based on symbols boundaries. The adjustment may comprise sign inversion. Adjusted and unadjusted waveforms may be generated for two or more of the time-domain signals; and selection may be made between generated adjusted waveforms based on particular criteria. The criteria may comprise lowest peak.
Methods and systems for reducing crosstalk using sequential non-linear vectoring
In one example embodiment, a method includes determining a first set of first lines and a second set of second lines in a system, obtaining input signals to be transmitted over the first set of first lines and the second set of second lines, determining a vectoring matrix, processing, within the first set, the incoming signals for the first lines in parallel based on the vectoring matrix, processing, within the second set, the input signals for the second lines in parallel based on the vectoring matrix and processing the first set and the second set sequentially based on the vectoring matrix, the processing the second set being based on at least a portion of the processing the incoming signals for the first lines.
SPUR CANCELLATION SYSTEM FOR MODEMS
A modem includes a modulator and a demodulator. The demodulator includes a direct current removing (DCR) circuit to transition between an acquisition mode, where the DCR circuit operates with a first loop gain; and a tracking mode, where the DCR circuit operates with a second loop gain. The second loop gain is smaller than the first loop gain, and the timing of the transition between the acquisition mode and tracking mode is programmable.
Harmonic selective full-band capture receiver with digital harmonic rejection calibration
A receiver includes circuitry configured to determine one or more first local oscillator (LO) harmonics that correspond to one or more first spectrum segments of a down-converted received signal based on characteristics of the received signal. The one or more first LO harmonics of the received signal are amplified by applying one or more first transconductance coefficients to one or more first harmonic selective transinductance amplifiers (TIAs) corresponding to the one or more first spectrum segments. Digitized outputs of the plurality of harmonic selective TIAs are calibrated based on an amount of signal leakage between the plurality of spectrum segments of the down-converted received signal.
Down-conversion circuit
A down-conversion circuit for a receiver circuit is disclosed, the down-conversion circuit comprises a first passive switching mixer arranged to down-convert a received radio frequency, RF, signal with a first local oscillator, LO, signal (LO1) having a first duty cycle for generating a first down-converted signal at an output port of the first passive switching mixer. The down-conversion circuit further comprises a second passive switching mixer arranged to down-convert the received RF signal with a second LO signal (LO2) having the same LO frequency as the first LO signal (LO1) and a second duty cycle, different from the first duty cycle, for generating a second down-converted signal at an output port of the second passive switching mixer. In addition, the down-conversion circuit comprises a passive output combiner network operatively connected to the output ports of the first passive switching mixer and the second passive switching mixer and arranged to combine the first and the second down-converted signals such that harmonically down-converted signal content present in the first down-converted signal and harmonically down-converted signal content present in the second down-converted signal cancel in a combined output signal of the down-conversion circuit. The passive output combiner network is tunable to adjust magnitudes and phases of the first and the second down-converted signals. A related quadrature down-conversion circuit, a related receiver circuit, a related communication device, and a related calibration method are also disclosed.
Apparatus and method for sending and receiving broadcast signals
A broadcast signal receiver is provided. The broadcast signal receiver comprises a demodulator configured to demodulate a received broadcast signal, a frame parser configured to parse a signal frame of the demodulated broadcast signal, the signal frame comprising a preamble and Layered Division Multiplexing (LDM) data, and the preamble carrying signaling information, a time deinterleaver configured to time deinterleave the LDM data, a first demapping/decoding unit configured to obtain core layer data by demapping and Forward Error Correction (FEC)-decoding the LDM data, an interference removal unit configured to remove the core layer data from the LDM data and to output enhanced layer data, a second demapping/decoding unit configured to demap and FEC-decode the enhanced layer data, and an output processor configured to process at least one of the core layer data or the enhanced layer data and to output a data stream.