Methods and various structures provide for loopback tuning, testing, and calibrating of a transceiver, including: supplying RF drive to both a transmitter and a receiver of the transceiver from one oscillator; applying a modulation waveform to a transceiver block of the transceiver to produce an amplitude-modulated signal; converting a sideband of the amplitude-modulated signal to a baseband signal having a frequency suitable for processing by a receiver digital block, where processing the baseband signal produces a digital output; and performing tuning, testing, and calibrating of the transceiver block, based at least in part on the digital output.

A system for interference mitigation including a transmit coupler that samples the RF transmit signal to create a sampled RF transmit signal; a transmit analog canceller that transforms the RF transmit signal to an RF interference cancellation signal, according to a first configuration state; a first receive coupler that combines the RF interference cancellation signal and the RF receive signal to generate a composite RF receive signal; a sampling analog interference filtering system that, in order to remove interference in the transmit band, filters the sampled RF transmit signal to generate a cleaned transmit signal; a first frequency downconverter that converts the transmit signal to a BB transmit signal; a second frequency downconverter that converts the composite RF receive signal to a composite BB receive signal; and an analog-to-digital converter that converts the transmit signal to a digital transmit signal.

A polar transmitter provided for transmitting a phase/frequency modulated and amplitude modulated transmit signal and a method for generating a transmit signal using a polar transmitter are described. An example polar transmitter comprises a phase locked loop for generating a phase/frequency modulated precursor of the transmit signal. The phase locked loop comprises at its input a phase error detection unit for detecting a phase error of the precursor fed back from the output of the phase locked loop to the phase error detection unit as a feedback signal. The polar transmitter comprises a digital amplitude modulator for amplitude modulation of the precursor, resulting in the transmit signal. The digital amplitude modulator is arranged within the phase locked loop for amplitude modulation of the precursor before being output by the PLL. The phase error detection unit is further provided for detecting the amplitude of the feedback signal.

A radio-frequency circuit includes a first filter having a first passband including a first band; a second filter having a second passband including the first band; a power amplifier that amplifies a radio-frequency signal in the first band; and a switch that switches between connection between the first filter and the power amplifier and a connection between the second filter and the power amplifier. Under a condition that a transmission of the radio-frequency signal in the first band is not V2X communication, the first filter is connected to the power amplifier via the switch. Under a condition that the transmission of the radio-frequency signal in the first band is the V2X communication, the second filter is connected to the power amplifier via the switch.

A direct digital radio having a high-speed RF front end in communication with an antenna, and a radio subsystem that can be configured to form a programmable multi-standard transceiver system. The high-speed RF front including RF inputs configured to receive a plurality of radio frequencies (e.g., frequencies between 400 MHz to 7.2 GHz, millimeter wave frequency signals, etc.) and wideband low noise amplifiers provides amplified signals to RF data converters, analog interfaces, digital interfaces, component interfaces, etc. The programmable multi-standard transceiver is operable in frequencies compatible with multiple networks such as private LTE and 5G networks as well as other wireless IoT standards and WiFi in multi-standard network access equipment. The programmable multi-standard transceiver can greatly reduce complexity for the baseband processing, lower the cost of the overall transceiver system, reduce power consumption, and at the same time, benefit from improvements on the digital functions through integration.

The signal generating device includes a signal generator that generates a signal of a predetermined frequency, a high-pass filter bank that removes a signal of a frequency lower than or equal to a first frequency lower than a predetermined frequency from the signal generated by the signal generator, a YTF that removes a signal outside a predetermined frequency band from the signal output by the high-pass filter bank, a splitter that distributes the signal output by the YTF into a plurality of signals, two amplifiers that adjust levels of the signals distributed by the splitter, respectively, and two low-pass filter banks that remove signals of frequencies equal to or higher than a second frequency which is higher than the predetermined frequency from each of the signals output by the amplifiers.

A method includes transmitting, by a transmitter and over a transmit channel to a remote device, a signal that includes a plurality of signal points and receiving, by a receiver and over a receive channel from the remote device, a response signal that includes a plurality of response points corresponding to the plurality of signal points. The method also includes adjusting the plurality of signal points of the signal until logical values of the plurality of response points invert to produce an adjusted signal, estimating, based on the adjusted signal, a pulse response of the transmit channel, and applying equalization in the transmitter based on the estimated pulse response to reduce an effect of the pulse response on the signal.

Disclosed is a transmission radio frequency (RF) circuit including a transmission mixer configured to receive an intermediate frequency (IF) signal and up-convert the IF signal into an RF signal, a driving amplifier configured to amplify the RF signal, and an LLC filter electrically connected to a differential output of the transmission mixer and a differential input of the driving amplifier, the LLC filter comprising a first inductor connecting a first node of the differential output of the transmission mixer to a first intermediate node, a second inductor connecting a second node of the differential output of the transmission mixer to a second intermediate node, a third inductor connecting the first intermediate node to the second intermediate node, and a capacitor in parallel with the third inductor.

A device for monitoring a health parameter in a person is disclosed. The device includes a semiconductor substrate, at least one transmit antenna configured to transmit millimeter range radio waves over a 3D space below the skin surface of a person, multiple receive antennas configured to receive radio waves, the received radio waves including a reflected portion of the transmitted radio waves, wherein the semiconductor substrate includes circuits for processing signals received on the multiple receive antennas, wherein processing signals includes mixing signals of two different frequencies, and wherein the semiconductor substrate includes at least one output configured to output a signal that corresponds to a health parameter of a person in response to received radio waves.

Aspects of wireless communication are described, including a radiofrequency (RF) amplifier chip, configured for transmitting or receiving data, comprising a first substrate comprising a first material and a second substrate comprising a second material that is different from the first material. The first substrate and the second substrate may be lattice-matched such that an interface region between the first substrate and the second substrate exhibits an sp3 carbon peak at about 1332 cm.Math..sup.1 having a full width half maximum of no more than 5.0 cm.Math..sup.1 as measured by Raman spectroscopy. In some aspects, the first substrate and said second substrate permit said chip to transmit or receive data at a transfer rate of at least 500 megabits per second and a frequency of at least 8 GHz. In some aspects, the RF amplifier chip is part of a satellite transmitter.