A signal mixing circuit device includes a first mixer, a second mixer and a signal amplifying circuit serially connected to the first mixer; the first mixer includes an RF signal input terminal for receiving an RF signal, LO signal input terminals for sampling a first and second LO signals, a first mixed-signal output terminal for outputting a first mixed signal and a second mixed-signal output terminal for outputting a second mixed signal; the second mixer includes an input terminal connected to a capacitor, two mixed-signal output terminals respectively connected to the first and second mixed-signal output terminals of the first mixer, LO signal input terminals for inversely sampling the first and second LO signals. With the double-balance nature of the second mixer core, the noise at the LO signal input terminals of the first mixer can be cancelled. A receiver includes the signal mixing circuit device is also disclosed.

A mixer circuitry comprises a mixer, a local oscillator (LO) leakage detector, a digital LO leakage cancellation controller and a DAC arrangement. The mixer is configured to mix a first LO signal having an LO frequency f.sub.LO with an intermediate frequency (IF) signal and generate an output signal, i.e. a wanted signal. The LO leakage detector measures the LO leakage at the output of the mixer in the presence of the wanted signal. Then in the digital LO leakage cancellation controller, a digital algorithm is run that automatically adjusts the LO leakage in the mixer by steering the digital-to-analog converter arrangement such that the intermediate frequency input signal level to the mixer is adjusted.

A near field communication device configured to receive a signal from an antenna and to generate a first in-phase signal and a first quadrature-phase signal by multiplying the signal with a first oscillation signal and a second oscillation signal; a first and second low-pass filter configured to generate a second in-phase signal and a second quadrature-phase signal; a first and second analog-to-digital converter configured to generate a third in-phase signal and a third quadrature-phase signal; a digital signal extractor configured to generate a first signal and a second signal based on the third in-phase signal, the third quadrature-phase signal, a first look-up table, and a second look-up table, select one from among the first signal and the second signal based on a signal pattern, and output the selected one as an extraction signal; and a modem configured to receive the extraction signal and to demodulate the extraction signal.

A radio receiver comprises a local oscillator arrangement and a controller. The local oscillator arrangement is arranged to provide a signal for down-conversion of radio frequency signal to an intermediate frequency or a baseband frequency in the radio receiver, and the local oscillator arrangement is capable of selectably providing multiple frequency generation qualities. The controller is arranged to estimate a tolerable frequency generation quality for the current operation of the radio receiver or determine whether the current operation of the radio receiver is satisfactory in sense of a currently provided frequency generation quality, and based on the estimation or determination adjust frequency generation quality of the local oscillator arrangement by selecting one of the multiple frequency generation qualities. A radio arrangement, a method and a computer program are also disclosed.

A beam forming device includes a plurality of control circuits and a plurality of antenna elements. Each of the plurality of control circuits controls at least either phases or amplitudes of a plurality of input signals to generate a transmission signal. Each of the plurality of antenna elements outputs the transmission signal generated by a corresponding control circuit. A frequency range of the transmission signal generated by each of the control circuits is higher than frequency ranges of the input signals.

A receiver includes one or more mixers configured to sample an input analog signal at a plurality of discrete points in time to obtain a discrete-time sampled signal based on a local oscillating signal provided by a local oscillator; and a sample reordering circuit coupled to the one or more mixers and configured to reorder a sequence of samples received from the one or more mixers.

Circuits for continuous-time analog correlators are provided, comprising: a first VCO that receives an input signal and that outputs a first pulse frequency modulated (PFM) output signal; a second VCO that receives a reference signal and that outputs a second PFM output signal; a first phase frequency detector (PFD) that receives the first PFM output signal and the second PFM output signal and that produces a first PFD output signal; a first delay cell that receives the first PFM output signal and that produces a first delayed signal (DS); a second delay cell that receives the second PFM output signal and that produces a second DS; a second PFD that receives the first DS and the second DS and that produces a second PFD output signal; and a capacitor-digital-to-analog converter (capacitor-DAC) that receives the first PFD output signal and the second PFD output signal and that produces a correlator output.

According to one embodiment, a wireless communication apparatus includes receiver circuitry and transmitter circuitry. The receiver circuitry is configured to receive a first frame addressed to another apparatus, the first frame being transmitted by a first wireless communication apparatus, and estimate a difference between an oscillation frequency of an oscillator of the first wireless communication apparatus and an oscillation frequency of an oscillator of the wireless communication apparatus based on the first frame. The transmitter circuitry is configured to transmit a third frame at a frequency determined based on the difference during a period at least partially overlapping a period during which the first wireless communication apparatus transmits a second frame addressed to a second wireless communication apparatus.

An apparatus is disclosed for flexible beamforming using frequency-division multiplexing. In an example aspect, an apparatus includes an antenna array and a wireless transceiver with two or more dedicated receive paths respectively coupled to two or more antenna elements of the antenna array, two or more mixers, a first combiner, a second combiner, and a switching circuit. The first combiner has a first input coupled to a first dedicated receive path and an output coupled to an input of a first mixer. The second combiner has a first input coupled to an output of the first mixer and a second input coupled to an output of a second mixer. The switching circuit is configured to selectively connect a second dedicated receive path to a second input of the first combiner or connect the second dedicated receive path to an input of the second mixer.

The invention relates to a mixer for generating an analog output signal X.sub.OUT from an analog input signal X.sub.IN using a mixing signal having a mixing frequency f.sub.MIX, the mixer comprising: a scaler being configured to sample the analog input signal X.sub.IN at a plurality of discrete points in time k with a sampling frequency f.sub.S to obtain a sampled analog input signal X.sub.IN[k] having a continuous signal value, and to generate the analog output signal X.sub.OUT having a continuous signal value by scaling the sampled analog input signal X.sub.IN[k] on the basis of a plurality of scaling coefficients A[k], wherein the scaling coefficients A[k] are a time-discrete representation of the mixing signal.