Methods, systems, and devices for wireless communication are described. A user equipment (UE) may tune an auxiliary receiver within a first radio to a transmission frequency of a co-located second radio. The auxiliary receiver may downconvert a signal from the second radio so that the UE may generate an interference estimate and perform interference cancellation. In some cases, the auxiliary receiver may also be used to perform transmission corrections for transmissions of the first radio. For example, the auxiliary receiver may be used to enable gain control or digital predistortion. The auxiliary receiver may be selectively tuned to the transmission frequency of the first radio or the second radio based on whether the auxiliary receiver is being used to perform interference cancellation or transmission correction.

Methods, systems, and devices for wireless communication are described. A user equipment (UE) may tune an auxiliary receiver within a first radio to a transmission frequency of a co-located second radio. The auxiliary receiver may downconvert a signal from the second radio so that the UE may generate an interference estimate and perform interference cancellation. In some cases, the auxiliary receiver may also be used to perform transmission corrections for transmissions of the first radio. For example, the auxiliary receiver may be used to enable gain control or digital predistortion. The auxiliary receiver may be selectively tuned to the transmission frequency of the first radio or the second radio based on whether the auxiliary receiver is being used to perform interference cancellation or transmission correction.

The present invention provides a preamble sequence sending and receiving method and apparatus, and a system. The preamble sequence sending method includes: generating, by a transmit end, a frequency offset estimation sequence, where the frequency offset estimation sequence includes N subsequences each with a length of M, N is a positive integer greater than or equal to 2, and M is a positive integer; generating, by the transmit end, a prefix and a suffix based on the frequency offset estimation sequence; adding, by the transmit end, the prefix and the suffix before and after the frequency offset estimation sequence respectively to form a preamble sequence, where the prefix and the suffix are used for canceling multipath interference; and adding, by the transmit end, the preamble sequence to a data packet and sending the data packet to a receive end.

Embodiments of a mobile device transmitter and methods for transmitting signals in different signal dimensions are generally disclosed herein. The mobile device transmitter comprises a mapper to map a block of two or more input modulation symbols to different signal dimensions comprising two or more spatial dimensions, and linear transform circuitry to perform a linear transform on the block of mapped input modulation symbols to generate a block of precoded complex-valued output symbols such that each output symbol carries some information of more than one input modulation symbol. The mobile device also comprises transmitter circuitry to generate time-domain signals from the blocks of precoded complex-valued output symbols for each of the spatial dimensions for transmission using the two or more antennas. The precoded complex-valued output symbols are mapped to different signal dimensions comprising at least different frequency dimensions prior to transmission.

Embodiments of a mobile device transmitter and methods for transmitting signals in different signal dimensions are generally disclosed herein. The mobile device transmitter comprises a mapper to map a block of two or more input modulation symbols to different signal dimensions comprising two or more spatial dimensions, and linear transform circuitry to perform a linear transform on the block of mapped input modulation symbols to generate a block of precoded complex-valued output symbols such that each output symbol carries some information of more than one input modulation symbol. The mobile device also comprises transmitter circuitry to generate time-domain signals from the blocks of precoded complex-valued output symbols for each of the spatial dimensions for transmission using the two or more antennas. The precoded complex-valued output symbols are mapped to different signal dimensions comprising at least different frequency dimensions prior to transmission.

A circuit includes a summation circuit for receiving an input data signal and a feedback signal including a previous data bit. The summation circuit is configured to output a conditioned input data signal to a clock and data recovery circuit. A first flip-flop is coupled to an output of the summation circuit and is configured to receive a first set of bits of the conditioned input data signal and a first clock signal having a frequency that is less than a frequency at which the input data signal is received by the first summation circuit. A second flip-flop is coupled to the output of the summation circuit and is configured to receive a second set of bits of the conditioned input data signal and a second clock signal having a frequency that is less than the frequency at which the input data signal is received by the first summation circuit.

A circuit includes a summation circuit for receiving an input data signal and a feedback signal including a previous data bit. The summation circuit is configured to output a conditioned input data signal to a clock and data recovery circuit. A first flip-flop is coupled to an output of the summation circuit and is configured to receive a first set of bits of the conditioned input data signal and a first clock signal having a frequency that is less than a frequency at which the input data signal is received by the first summation circuit. A second flip-flop is coupled to the output of the summation circuit and is configured to receive a second set of bits of the conditioned input data signal and a second clock signal having a frequency that is less than the frequency at which the input data signal is received by the first summation circuit.

A method and apparatus in a noise cancellation system that receives a noise reference signal via a noise reference signal input port, and performs at least one of procedures a and b set forth below for reducing noise in a DSL data signal transmitted on a DSL transmission line to which the noise cancellation system is coupled: a.i.) creating a noise free representation of a DSL synchronization symbol repeatedly occurring in the transmitted DSL data signal, and a.ii.) reducing the noise in the transmitted DSL data signal based on the noise free representation of the DSL synchronization symbol and the received noise reference signal, and b.i.) analyzing at least one of the received noise reference signal and the transmitted DSL data signal to identify one or more frequency bands in which to de-emphasize noise cancellation in the transmitted DSL data signal, and b.ii.) causing the noise cancellation system to de-emphasize noise cancellation in the identified one or more frequency bands of the transmitted DSL data signal, responsive to the analysis.

An electronic device includes a transceiver connected to a differential signal transmission line for transmitting a differential signal through a pair of signal lines to communicate with one or a plurality of other devices connected to the differential signal transmission line. The electronic device includes: a suppression circuit that is operated by a power source voltage to suppress waveform distortion in the differential signal transmitted through the differential signal transmission line; and a power source controller that controls supply or cutoff of the power source voltage to the suppression circuit in response to a change in a differential voltage between the pair of signal lines.

Embodiments of this disclosure provide an apparatus and method for estimating a frequency offset, an apparatus and method for estimating a channel spacing and a system. The apparatus for estimating a frequency offset includes: a synchronization extracting unit configured to perform a training sequence synchronization extraction on a receiving sequence containing a periodic training sequence to obtain the training sequence; a delay correlation processing unit configured to parallelly perform autocorrelation operations of different delay amounts on the training sequence to obtain multiple parallel correlation sequences; a superimposition processing unit configured to perform a superimposition operation on the multiple parallel correlation sequences to obtain a single sequence; and a frequency offset estimating unit configured to determine a frequency offset according to a phase of a synchronization position of the single sequence in the training sequence. With the embodiments of this disclosure, anti-noise characteristic of the frequency offset estimation may be improved.