A magnetic resonance imaging (MRI) system (100, 400, 500) includes a wireless RF station (20, 320, 420, 520, 620) which is associated with one or more RF coils which sense the magnetic resonance (MR) signal emitted from a subject under MRI examination. The wireless RF station communicates digital data representing the sensed MR signal to an MRI controller (124) for further processing, which may include display. An internal clock (2202, 3202) in the wireless RF station is precisely synchronized with the MRI controller clock (108, 2101, 3101), with carrier phase synchronization and code phase tracking of a predefined code sequence such as a pseudo random number (PRN) sequence.

The present invention relates to calibration of an electronic device. An operation method of an electronic device may comprise the operations of: setting a first path for a first calibration of a transmission path; performing the first calibration of the transmission path by using the first path; setting a second path for a second calibration of a transceiving path; performing the second calibration of the transceiving path by using the second path; and generating data indicating a result of calibration of a reception path, on the basis of a result obtained by the first calibration and the second calibration. Various other embodiments are possible.

A radar system includes a transmitter circuit, which transmits a radar wave having a chirp frequency gradually increasing or decreasing to a target, and a frequency conversion circuit, which demodulates a signal of the radar wave reflected at the target by frequency-conversion in correspondence to the chirp frequency. A radar signal processor includes a variable amplifier connected to an output side of the frequency conversion circuit, and a feedback circuit which detects an output of the variable amplifier as a detection signal and feeds back a signal of a frequency band included in the detection signal to an input of the variable amplifier. The feedback circuit is configured to cut off and not cut off a frequency band including a DC offset transient response frequency, which occurs at time of frequency conversion by the frequency conversion circuit, during a specified period and a period other than the specified period, respectively. The specified period is a predetermined first period from starting of a demodulation operation of the frequency conversion circuit and/or a predetermined second period from ending of the demodulation operation of the frequency operation of the frequency conversion circuit.

A radar system includes a transmitter circuit, which transmits a radar wave having a chirp frequency gradually increasing or decreasing to a target, and a frequency conversion circuit, which demodulates a signal of the radar wave reflected at the target by frequency-conversion in correspondence to the chirp frequency. A radar signal processor includes a variable amplifier connected to an output side of the frequency conversion circuit, and a feedback circuit which detects an output of the variable amplifier as a detection signal and feeds back a signal of a frequency band included in the detection signal to an input of the variable amplifier. The feedback circuit is configured to cut off and not cut off a frequency band including a DC offset transient response frequency, which occurs at time of frequency conversion by the frequency conversion circuit, during a specified period and a period other than the specified period, respectively. The specified period is a predetermined first period from starting of a demodulation operation of the frequency conversion circuit and/or a predetermined second period from ending of the demodulation operation of the frequency operation of the frequency conversion circuit.

An apparatus includes a radio-frequency (RF) receiver. The RF receiver includes an analog-to-digital converter (ADC) to convert an analog input signal to a digital output signal in response to an ADC clock signal. The RF receiver further includes a frequency generator to selectively provide either a clock signal to be provided as the ADC clock signal or a signal to be used for in-phase-quadrature (IQ) calibration of the RF receiver.

An apparatus includes a radio-frequency (RF) receiver. The RF receiver includes an analog-to-digital converter (ADC) to convert an analog input signal to a digital output signal in response to an ADC clock signal. The RF receiver further includes a frequency generator to selectively provide either a clock signal to be provided as the ADC clock signal or a signal to be used for in-phase-quadrature (IQ) calibration of the RF receiver.

The present disclosure provides a radio frequency (RF) front-end of a low power consumption and fully automatic adjustable broadband receiver, including a low-noise amplification module, amplifying an broadband single-ended RF signal, and converting it into differential current signal; a local oscillator, generating a local oscillator signal; an quadrature mixer, quadraturely mixing the differential current signal and the local oscillator signal to generate intermediate frequency differential current signals; a transimpedance amplifier, converting the intermediate frequency differential current signal into an intermediate frequency differential voltage signal; an IIP2 calibration module, reducing the IIP2 effect of the RF front end; a received signal strength indicator module, sending the first amplification factor control signal and the differential mismatch control signal to the low noise amplification module, and sending the second amplification factor control signal to the transimpedance amplifier, thereby making the intermediate frequency differential voltage signals meet the requirements of the amplitude and mismatch.

A test instrument may include a transmitter configured to transmit signals to a unit under test, a receiver configured to receive signals from the unit under test, and a controller configured to generate a transmitter compensation filter by (i) transmitting, with the transmitter, complex multi-sine signals over a first plurality of observed frequencies within a predetermined baseband frequency range, (ii) estimating a first plurality of frequency responses that compensate for in-phase and quadrature (IQ) imbalance at the first plurality of observed frequencies within the predetermined baseband frequency range, and (iii) determining, using the first plurality of frequency responses, a transmitter polynomial surface, and to compensate, using the transmitter compensation filter, at least one of the signals to be transmitted by the transmitter to reduce IQ imbalance in the transmitted signals, including using the transmitter polynomial surface to calculate a frequency response that reduces the IQ imbalance in the transmitted signals.

The disclosure relates to a pre-5th-generation (5G) or 5G communication system to be provided for supporting higher data rates beyond 4th-generation (4G) communication system such as long term evolution (LTE). An operation method of a device for upconversion in a wireless communication system is provided. The method includes receiving a first local oscillator (LO) signal, generating a second LO signal, based on the first LO signal and cross-coupled latches, receiving an input signal, generating an upconverted frequency, based on the second LO signal and the input signal, generating an output signal obtained by processing a harmonic component included in the upconverted frequency, and transmitting the generated output signal.

The disclosure relates to a pre-5th-generation (5G) or 5G communication system to be provided for supporting higher data rates beyond 4th-generation (4G) communication system such as long term evolution (LTE). An operation method of a device for upconversion in a wireless communication system is provided. The method includes receiving a first local oscillator (LO) signal, generating a second LO signal, based on the first LO signal and cross-coupled latches, receiving an input signal, generating an upconverted frequency, based on the second LO signal and the input signal, generating an output signal obtained by processing a harmonic component included in the upconverted frequency, and transmitting the generated output signal.