Patent classifications
H04L25/03847
Reception interface circuits supporting multiple communication standards and memory systems including the same
A reception interface circuit includes a termination circuit, a buffer and an interface controller. The termination circuit is configured to change a termination mode in response to a termination control signal. The buffer is configured to change a reception characteristic in response to a buffer control signal. The interface controller is configured to generate the termination control signal and the buffer control signal such that the reception characteristic of the buffer is changed in association with the change in the termination mode. The reception interface circuit may support various communication standards by changing the reception characteristic of the buffer in association with the termination mode. Using the reception interface circuit, communication efficiency of transceiver systems such as a memory system and/or compatibility between a transmitter device and a receiver device may be improved.
ELEMENT MANAGEMENT SYSTEM FOR ANALOG AMPLIFIER WITHOUT CHANNEL MANAGEMENT
A system and method are provided herein for managing an amplifier at an intermediate location in a twisted pair line between a digital subscriber line (DSL) access multiplexer and a customer premises equipment, for high data rate broadband operation. The system may include a DSL access multiplexer, an amplifier, a local communication interface and a host computer, programmed to execute an element management system service application.
Feed-forward filtering device and associated method
A filtering device includes a low-pass filter (LPF), a noise estimation circuit and a first combining circuit. The LPF receives and filters a pre-filtering signal to generate an output signal of the filtering device. The noise estimation circuit estimates an estimated noise signal according to the output signal and the pre-filtering signal. The first combining circuit subtracts the estimated noise signal from an input signal of the filtering device to generate the pre-filtering signal.
Method and system for controlling an amplifier of a communications device
Embodiments of a method and a system controlling an amplifier of a communications device are disclosed. In an embodiment, a method for controlling an amplifier of a communications device involves checking for a data reception at the communications device and freezing a gain of the amplifier if the data reception is detected.
FEED-FORWARD FILTERING DEVICE AND ASSOCIATED METHOD
A filtering device includes a low-pass filter (LPF), a noise estimation circuit and a first combining circuit. The LPF receives and filters a pre-filtering signal to generate an output signal of the filtering device. The noise estimation circuit estimates an estimated noise signal according to the output signal and the pre-filtering signal. The first combining circuit subtracts the estimated noise signal from an input signal of the filtering device to generate the pre-filtering signal.
METHOD FOR FREQUENCY- AND TIME-SELECTIVE INTERFERENCE SUPPRESSION FOR A COMMUNICATION SYSTEM BASED ON OFDM, AND RECEIVER THEREFOR
A method for frequency- and time-selective interference suppression for a communication system based on OFDM, and a receiver therefor. To achieve a much lower bit error rate at the output of the receiver or to permit greater interference or a lower signal-to-noise ratio (in a prior art L-DACS1 receiver, at least 45 nautical miles) for the same transmission power, the invention provides: a filter bank pulse blanking method FBPB in which the sampled received signal is applied to a blanking unit for frequency-selective pulse blanking, which blanking unit consists of an analysis filter bank having M sub-bands; a module for frequency-selective pulse blanking of the sub-band signals; and a synthesis filter bank, which reassembles the signal. The analysis filter bank, which breaks down the received signal into multiple sub-bands on a frequency-selective basis, is used before OFDM windowing, such that the sub-band breakdown applies pulse blanking on a sub-band-selective basis.
Active linear amplifier inside transmitter module
In one example embodiment, a transmitter module includes a header electrically coupled to a chassis ground. First and second input nodes are configured to receive a differential data signal. A buffer stage has a first node coupled to the first input node and a second node coupled to the second input node. An amplifier stage has a fifth node coupled to a third node of the buffer stage and a sixth node coupled to a signal ground that is not coupled to the chassis ground. An optical transmitter has an eighth node coupled to a seventh node of the amplifier stage and a ninth node configured to be coupled to a voltage source. A bias circuit is configured to couple a fourth node of the buffer stage to a bias current source.
Method of and circuit for predistortion for a power amplifier
A digital predistortion (DPD) system includes an input configured to receive a DPD input signal. The DPD system includes a first predistortion circuit configured to provide a first signal path coupled to the input to generate a first predistortion signal. The first predistortion circuit includes a first infinite impulse response (IIR) filter. A second predistortion circuit is configured to provide a second signal path coupled to the input in parallel with the first signal path to generate a second predistortion signal. The second predistortion circuit includes a second IIR filter. A combiner circuit is configured to combine the first predistortion signal and the second predistortion signal to generate a DPD output signal.
Transmitter and interference cancellation method
Present application provides embodiments of a transmitter and an interference cancellation method. The transmitter includes: a first digital predistorter (DPD), a power amplifier (PA), and a first processor located on a feedback channel of the transmitter and separately connected to the PA and the first DPD. The first processor performs, according to a feedback cancellation signal, interference cancellation on a signal of the feedback channel, to acquire a first mixed signal, and sends the first mixed signal to the first DPD. The first DPD is configured to perform linear predistortion processing according to a first baseband signal on a first transmit channel and the first mixed signal, to generate a first predistortion signal. The PA is configured to amplify and then transmit a to-be-transmitted signal using an antenna. The to-be-transmitted signal is the first predistortion signal or a signal obtained according to the first predistortion signal.
Partial response signaling techniques for single and multi-carrier nonlinear satellite systems
New partial response signaling systems and methods for high spectral efficiency communications are described. In a first implementation, a communication system includes a partial response signaling transmitter and a nonlinear satellite transponder. The partial response signaling transmitter includes a partial response transmit filter configured to convert complex-valued data symbols to a transmit signal using a partial response pulse shaping function; and a modulator configured to modulate the transmit signal onto a carrier wave. The transponder receives and non-linearly amplifies the modulated transmit signal for broadcast to receivers. In a second implementation, a receiver includes circuitry for downconverting a received input signal; a partial response filter with a partial response impulse function for filtering the downconverted signal; circuitry for downsampling the partial response filtered signal; circuitry for equalizing the downsampled signal; and a linear and non-linear interference cancellation module including circuitry for removing linear and non-linear ISI in the input signal.