A method includes producing a plurality of TX LO signals by a first LO generator comprising a first frequency doubler and a first frequency divider, the first frequency doubler configured to receive a VCO signal having a first frequency and generate a first signal fed into the first frequency divider, the first signal having a second frequency that is twice the first frequency, producing a plurality of MRX LO signals by a second LO generator comprising a second frequency doubler and a second frequency divider, the second frequency doubler configured to receive the VCO signal and generate a second signal fed into the second frequency divider, the second signal having the second frequency, configuring the TX to operate at a first LO frequency equal to the second frequency, and configuring the MRX to operate at a second LO frequency equal to the first frequency through disabling the second frequency doubler.

A method for communicating between a first radio frequency communications device including a first local oscillator and a second radio frequency communications device including a second local oscillator includes receiving a packet using a receiver of the first radio frequency communications device. The method includes detecting an average frequency offset based on sequential samples of the packet. The method includes applying a first adjustment to the first local oscillator to reduce a frequency offset between the first local oscillator and the second local oscillator. The first adjustment is based on the average frequency offset. The method includes, after adjusting the first local oscillator, transmitting a second packet to the second radio frequency communications device by the first radio frequency communications device using the first adjustment and the first local oscillator.

A RF downconverter-tuner system is provided. A RF downconverter-tuner system to convert one or more input signals into a lower range of frequency bands, comprising one or more RF input ports for receiving the one or more input signals, one or more RF output ports for transmitting the output signal and a plurality of dual-mode switches coupled to two or more of the one or more RF input ports, the one or more RF output ports and one or more receive chain comprising one or more mixers for converting the one or more input signals into the lower range of frequency bands, a plurality of filters, a bypass mode, a back-end receiver coupled to the one or more RF output ports, an oscillator implemented with a frequency synthesis circuit, a plurality of amplifier stages, one or more signal detection circuits and a plurality of controller ports.

Described herein are systems and methods that allow for correcting a residual frequency offset in the GHz frequency range by using low-complexity analog circuit implementations of a broad-band frequency detector that comprises two analog polyphase filters in a dual configuration. Each filter comprises an RC network of cross-coupled capacitors that facilitate filters with opposite passbands and opposite stop-bands. In various embodiments, the outputs of the two filters are combined to obtain power metrics that when subtracted from each other, deliver a measure of the imbalance between the positive and negative halves of a frequency spectrum. Since the measure is substantially proportional to a frequency offset within a linear range spanning 5 GHz or more, the polyphase filters may be used in a broad-band frequency detector that, based on the measure, adjusts the frequency offset.

A signal up-conversion system is described. The system comprises a signal input for receiving an input signal to be up-converted; an oscillator system for generating an up-conversion signal having a selectable frequency; a mixer coupled to the input and to the oscillator, for combining the input signal and the up-conversion signal and to generate an up-converted signal; at least two filters, each of the at least two filters having different filtering characteristics; a signal output; a switch system configured to couple one of the at least two filters into a signal path between the output of the mixer and the signal output; and a controller configured to control a frequency of the up-conversion signal and a filter of the at least two filters coupled into the signal path by the switch system. A method switching between up-conversion frequencies is also described.

A mechanical frequency upconverter includes a body having a cavity. A low-frequency membrane is coupled to the body and arranged adjacent to the cavity. The low-frequency membrane is a permanent magnet or a permanent magnet is affixed to the low-frequency membrane. A high-frequency membrane is coupled to the body and arranged adjacent to the cavity. The high-frequency membrane includes a magnetic metal. Oscillation of the low-frequency membrane at a first frequency causes the high-frequency membrane to oscillate at a second frequency, which is higher than the first frequency.

A mechanical frequency upconverter includes a body having a cavity. A low-frequency membrane is coupled to the body and arranged adjacent to the cavity. The low-frequency membrane is a permanent magnet or a permanent magnet is affixed to the low-frequency membrane. A high-frequency membrane is coupled to the body and arranged adjacent to the cavity. The high-frequency membrane includes a magnetic metal. Oscillation of the low-frequency membrane at a first frequency causes the high-frequency membrane to oscillate at a second frequency, which is higher than the first frequency.

A frequency multiplier includes an input section to receive a quadrature phase input signal having an input frequency, a mixer section coupled to the input section by a common mode node that forms a path for the common mode signal current to flow to the mixer section and magnetically coupled to the common mode node or capacitively coupled to the input section to generate a differential switching voltage at odd multiples of twice the input frequency, which switching voltage is applied to inputs of the mixer section, and an output section magnetically coupled to the mixer section, the output section being configured to generate an output voltage having a dominate frequency and sub-dominate frequencies spaced apart by the first multiple, the dominate frequency of the output voltage being a second multiple of the input frequency, where the second multiple is greater than the first multiple. Various arrangements are provided.

A frequency multiplier includes an input section to receive a quadrature phase input signal having an input frequency, a mixer section coupled to the input section by a common mode node that forms a path for the common mode signal current to flow to the mixer section and magnetically coupled to the common mode node or capacitively coupled to the input section to generate a differential switching voltage at odd multiples of twice the input frequency, which switching voltage is applied to inputs of the mixer section, and an output section magnetically coupled to the mixer section, the output section being configured to generate an output voltage having a dominate frequency and sub-dominate frequencies spaced apart by the first multiple, the dominate frequency of the output voltage being a second multiple of the input frequency, where the second multiple is greater than the first multiple. Various arrangements are provided.

A device for monitoring a health parameter of a person is disclosed. The device includes a semiconductor substrate including at least one transmit component and multiple receive components, at least one transmit antenna configured to transmit millimeter range radio waves over a 3D space below the skin surface of a person, and 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 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, and wherein the at least one transmit antenna is collocated with the at least one transmit component and the multiple receive antennas are collocated with respective ones of the multiple receive components.