An apparatus, a system, and a chip are provided for improving RF system performance in MRI systems. The apparatus includes a radio-frequency (RF) coil array disposed at least partially in a coil housing, where the RF coil array may include at least one coil configured to receive magnetic resonance (MR) RF signals. The apparatus also includes a mixer disposed in the coil housing and electronically connected to the RF coil array, where the mixer converts MR RF signals from the RF coil array to intermediate-frequency (IF) signals. An electronic amplifier is disposed in the coil housing. The electronic amplifier is electronically connected to the mixer and is configured to amplify IF signals from the mixer to amplified IF signals.

This disclosure provides systems, methods, and devices for wireless communications that support downconversion of signals with improved harmonic rejection. In a first aspect, an apparatus includes a first plurality of mixers with each mixer coupled to two oscillating signals that are 180 degrees apart in phase; a second plurality of mixers with each mixer coupled to two oscillating signals that are 180 degrees apart in phase, wherein a combined load of the first plurality of mixers and the second plurality of mixers on the plurality of oscillating signals is symmetric as to each oscillating signal of the plurality of oscillating signals; and a shared capacitor coupling the RF input to the first plurality of mixers and the second plurality of mixers. Other aspects and features are also claimed and described.

This disclosure provides systems, methods, and devices for wireless communications that support downconversion in a radio frequency (RF) system. In a first aspect, an apparatus for wireless communications includes a first mixer coupled to an input node; a second mixer coupled to the input node; and a first mixer bias circuit configured to output a first local oscillator (LO) signal, the first mixer bias circuit coupled to the first mixer and to the second mixer to output the first LO signal to the first mixer and to the second mixer. Other aspects and features are also claimed and described.

This disclosure provides systems, methods, and devices for wireless communication that support reconfiguring degeneration components in a converged RF transceiver supporting carrier aggregation across sub-6 GHz frequency bands and mmWave frequency bands. In a first aspect, an apparatus includes an input port configured to receive a mixer input signal; a first mixer forming at least a portion of an HRM mixer and coupled to the input port; a first configurable degeneration component of a first processing path coupled between the input port and the first mixer; and a controller coupled to the first degeneration component, wherein the controller is configured to control a first aspect of a first degeneration component. Other aspects and features are also claimed and described.

A mobile terminal performing harmonic rejection includes a plurality of baseband units generating a baseband signal; a plurality of up-converters converting the baseband signal into a radio frequency (RF) signal; and a controller controlling phases of a plurality of signals applied to the plurality of baseband units and the plurality of up-converters. Meanwhile, the controller may perform at least one of a harmonic rejection mode, a first non-harmonic rejection mode for improving a signal-to-noise ratio (SNR), and a second non-harmonic rejection mode for improving linearity to provide a transmitting part having improved harmonic distortion characteristics and the mobile terminal having the transmitting part.

The present technology relates to a signal processing apparatus and method capable of increasing a harmonic rejection ratio while suppressing an increase in power consumption. In one aspect of the present technology, two local signals having a 1/3 duty ratio and phases mutually shifted by a 1/2 period are mixed with each signal of a differential signal, and a difference between results of the mixing of the two local signals is calculated. The present technology can be applied to, for example, a signal processing apparatus, a transmission apparatus, a reception apparatus, a communication apparatus, an electronic apparatus having a transmission function, a reception function, or a communication function, or a computer that controls those apparatuses.

A mobile terminal performing harmonic rejection includes a plurality of baseband units generating a baseband signal; a plurality of up-converters converting the baseband signal into a radio frequency (RF) signal; and a controller controlling phases of a plurality of signals applied to the plurality of baseband units and the plurality of up-converters. Meanwhile, the controller may perform at least one of a harmonic rejection mode, a first non-harmonic rejection mode for improving a signal-to-noise ratio (SNR), and a second non-harmonic rejection mode for improving linearity to provide a transmitting part having improved harmonic distortion characteristics and the mobile terminal having the transmitting part.

The present application provides a window function processing module including an integrating circuit, configured to receive an integrating input signal, the integrating circuit comprising an operational amplifier; an integrating capacitor, coupled to an output terminal and a first input terminal of the operational amplifier; and an adjustable impedance module, coupled between the first input terminal of the operational amplifier and an integrating input terminal of the integrating circuit, wherein the adjustable impedance module is controlled by at least one control signal to adjust an impedance value of the adjustable impedance module; and a control unit, coupled to the integrating circuit, configured to generate the at least one control signal according to a window function, to adjust the integration gain of the integrating circuit, such that the integrating output signal is related to an operation result of the integrating input signal and the window function.

An apparatus is disclosed for mixer biasing with baseband filter common-mode voltage. In an example aspect, the apparatus includes a mixer, a baseband filter, and a bias circuit. The mixer has a mixer transistor that is coupled to a bias node and a baseband node. The baseband filter is coupled to the mixer via the baseband node. The baseband filter is configured to operate with a common-mode reference voltage that is associated with a common-mode voltage applied at the baseband node. The bias circuit is coupled to the baseband filter and the bias node. The bias circuit is configured to receive the common-mode reference voltage from the baseband filter and generate, at the bias node, a bias voltage for biasing the mixer transistor based on the common-mode reference voltage.

An apparatus is disclosed for mixer biasing with baseband filter common-mode voltage. In an example aspect, the apparatus includes a mixer, a baseband filter, and a bias circuit. The mixer has a mixer transistor that is coupled to a bias node and a baseband node. The baseband filter is coupled to the mixer via the baseband node. The baseband filter is configured to operate with a common-mode reference voltage that is associated with a common-mode voltage applied at the baseband node. The bias circuit is coupled to the baseband filter and the bias node. The bias circuit is configured to receive the common-mode reference voltage from the baseband filter and generate, at the bias node, a bias voltage for biasing the mixer transistor based on the common-mode reference voltage.