In an embodiment, a communications system includes a first transmitter including a digital beamforming baseband section configured to receive an input signal to be transmitted, the input signal at a baseband frequency, and a modulation section electrically coupled to the digital beamforming baseband section and a first antenna of a phased array antenna. The modulation section is configured to receive a local oscillator signal at a first local oscillator frequency and apply a baseband frequency shift to the input signal to generate a baseband frequency shifted input signal. The modulation section generates a modulated signal based on the input signal. The communication system includes a second transmitter included in a second IC chip of the plurality of IC chips electrically coupled to a second antenna and configured to provide a second modulated signal at the carrier frequency and a second LO leakage signal at a second local oscillator frequency.

Parametric flat lenses, which are an alternative to conventional flat lenses, are described for performing near-field imaging and electronic beam scanning. These lenses can electronically direct the near or far fields, and in some cases even achieve a conversion gain. The lens incorporates a plurality of input and output antennas between which are a plurality of parametric mixers. The parametric mixers can be utilized as well to change phase relationships in accommodating different input pattern or directing the output in different ways. The disclosure also describes a proof of concept implementation using off the shelf components.

Parametric flat lenses, which are an alternative to conventional flat lenses, are described for performing near-field imaging and electronic beam scanning. These lenses can electronically direct the near or far fields, and in some cases even achieve a conversion gain. The lens incorporates a plurality of input and output antennas between which are a plurality of parametric mixers. The parametric mixers can be utilized as well to change phase relationships in accommodating different input pattern or directing the output in different ways. The disclosure also describes a proof of concept implementation using off the shelf components.

A phase shifter that includes an RF splitter is disclosed. The RF splitter is arranged so that an RF input signal is provided to, and split over portions of, a feed line that connects an antenna element with a radio transmitter/receiver/transceiver, thus realizing a feed line splitter. Feed line splitters described herein are provided with switches that allow changing a point at which the RF input signal is fed to the feed line, where the switches may be semiconductor-based or MEMS-based switches. The point at which the RF input signal is provided to the feed line to be split defines the electrical path length that the RF energy will travel down each respective path of the feed line splitter, which, in turn, changes the phase shift realized at each output of the feed line splitter. Different antenna elements may be coupled to different outputs of the feed line splitter.

A phase shifter that includes an RF splitter is disclosed. The RF splitter is arranged so that an RF input signal is provided to, and split over portions of, a feed line that connects an antenna element with a radio transmitter/receiver/transceiver, thus realizing a feed line splitter. Feed line splitters described herein are provided with switches that allow changing a point at which the RF input signal is fed to the feed line, where the switches may be semiconductor-based or MEMS-based switches. The point at which the RF input signal is provided to the feed line to be split defines the electrical path length that the RF energy will travel down each respective path of the feed line splitter, which, in turn, changes the phase shift realized at each output of the feed line splitter. Different antenna elements may be coupled to different outputs of the feed line splitter.

A method includes injecting a reference input signal into each Voltage Controlled Oscillator (VCO) of a number of VCOs forming a coupled VCO array to reduce a level of injection energy required therefor. The reference input signal is configured to control operating frequency of the coupled VCO array. The method also includes utilizing a phase shift circuit: between individual VCOs of the coupled VCO array and/or in a path of injection of the reference input signal into one or more VCO(s) of the individual VCOs, and mixing outputs of the number of VCOs with signals from antenna elements of an antenna array to introduce differential phase shifts in signal paths coupled to the antenna elements during performing beamforming with the antenna array. Further, the method includes reducing a phase-steering requirement of the coupled VCO array during the beamforming based on the utilization of the phase shift circuit.

A method includes injecting a reference input signal into each Voltage Controlled Oscillator (VCO) of a number of VCOs forming a coupled VCO array to reduce a level of injection energy required therefor. The reference input signal is configured to control operating frequency of the coupled VCO array. The method also includes utilizing a phase shift circuit: between individual VCOs of the coupled VCO array and/or in a path of injection of the reference input signal into one or more VCO(s) of the individual VCOs, and mixing outputs of the number of VCOs with signals from antenna elements of an antenna array to introduce differential phase shifts in signal paths coupled to the antenna elements during performing beamforming with the antenna array. Further, the method includes reducing a phase-steering requirement of the coupled VCO array during the beamforming based on the utilization of the phase shift circuit.

In an embodiment, a communications system includes a transmitter including a digital beamforming baseband section including a digital mixer, the digital beamforming section configured to receive an input signal to be transmitted, the input signal at a baseband frequency; and a modulation section electrically coupled to the digital beamforming baseband section, the modulation section including an up converter configured to receive a local oscillator signal at a local oscillator frequency. The digital mixer is configured to apply a baseband frequency shift to the input signal to generate a baseband frequency shifted input signal at a different frequency from the baseband frequency. The up converter is configured to up convert the baseband frequency shifted input signal based on the local oscillator signal to generate a modulated signal at a carrier frequency, wherein the local oscillator frequency is different from the carrier frequency.

In an embodiment, a communications system includes a transmitter including a digital beamforming baseband section including a digital mixer, the digital beamforming section configured to receive an input signal to be transmitted, the input signal at a baseband frequency; and a modulation section electrically coupled to the digital beamforming baseband section, the modulation section including an up converter configured to receive a local oscillator signal at a local oscillator frequency. The digital mixer is configured to apply a baseband frequency shift to the input signal to generate a baseband frequency shifted input signal at a different frequency from the baseband frequency. The up converter is configured to up convert the baseband frequency shifted input signal based on the local oscillator signal to generate a modulated signal at a carrier frequency, wherein the local oscillator frequency is different from the carrier frequency.

A method includes separating phase of Local Oscillator (LO) signals generated by individual Voltage Controlled Oscillators (VCOs) of a coupled VCO array through varying voltage levels of voltage control inputs thereto. The method also includes frequency multiplying an output of each individual VCO of the coupled VCO array to increase a range of phase differences between the phase separated LO signals generated by the individual VCOs. Further, the method includes mixing the frequency multiplied outputs of the individual VCOs with signals from antenna elements of an antenna array to introduce differential phase shifts in signal paths coupled to the antenna elements during performing beamforming with the antenna array.