A multi-antenna transceiver system is disclosed. The system comprises a group of transceiver chips, wherein each transceiver chip has a respective chip-associated (e.g., on-chip) frequency generator configured to provide a respective conversion frequency, and wherein each transceiver chip is configured to use the respective conversion frequency for on-chip frequency conversion of a transceiver signal. The system also comprises a controller adapted to cause configuration of the respective chip-associated frequency generator of at least one of the transceiver chips, wherein the configuration comprises dynamically setting the respective conversion frequency. In some embodiments, the controller comprises a single piece of circuitry separate from the transceiver chips. The single piece of circuitry is adapted to cause configuration of the respective chip-associated frequency generator of two or more of the transceiver chips.

Embodiments describe systems, apparatuses, and methods for transmitting/receiving signal data to/from a plurality of transceiver modules. Devices in accordance with some embodiments can include a plurality of wireless transceiver modules, each wireless transceiver module to be communicatively coupled to a corresponding external transceiver module, one or more antennas to exchange signal data with the plurality of external transceiver modules, a radio frequency (RF) circulator, and one or more amplifiers to amplify the signal data received by the one or more antennas and signal data to be transmitted by the one or more antennas. The use of circulator prevents transmitting signals that may collide with each other and cause interference with the communications.

Apparatus and methods for front-end systems with directional couplers and a shared back switch are provided. In certain configurations, a method includes transmitting a first transmit signal from a first transmit port to an antenna port, generating a first coupled signal in response to the first transmit signal using a first directional coupler, providing the first coupled signal to a receive port by way of a first loopback selection switch and a shared back switch, transmitting a second transmit signal from a second transmit port to the antenna port, generating a second coupled signal in response to the second transmit signal using a second directional coupler, and providing the second coupled signal to the receive port by way of a second loopback selection switch and the shared back switch.

A radio frequency circuit includes a substrate, a first terminal disposed on a first principal surface of the substrate, a second terminal disposed on the first principal surface, a first-surface mounted component disposed on the first principal surface or inside the substrate, and a second-surface mounted component disposed on a second principal surface of the substrate which is opposite the first principal surface. A radio-frequency signal, which is input to the first terminal, is transmitted, for output from the second terminal, so as to make at least one round trip between the first principal surface and the second-surface mounted component, which is disposed on the second principal surface, through wiring lines disposed in the substrate.

Various embodiments disclosed herein enable steerable, time division duplex (“TDD”) communications channels at millimeter-wave frequency bands. Among other things, embodiments disclosed herein provide improved steering accuracy and power distribution, lower power consumption, and potentially longer service life than previous transceiver systems.

A local oscillator buffer circuit comprises a complementary common-source stage comprising a first p-channel transistor (MCSP) and a first n-channel transistor (MCSN), arranged such that their respective gate terminals are connected together at a first input node, and their respective drain terminals of each of is connected together at a buffer output node. A complementary source-follower stage comprises a second p-channel transistor (MSFP) and a second n-channel transistor (MSFN), arranged such that their respective gate terminals are connected together at a second input node, and their respective source terminals are connected together at the buffer output node.

A local oscillator buffer circuit comprises a complementary common-source stage comprising a first p-channel transistor (MCSP) and a first n-channel transistor (MCSN), arranged such that their respective gate terminals are connected together at a first input node, and their respective drain terminals of each of is connected together at a buffer output node. A complementary source-follower stage comprises a second p-channel transistor (MSFP) and a second n-channel transistor (MSFN), arranged such that their respective gate terminals are connected together at a second input node, and their respective source terminals are connected together at the buffer output node.

A radio frequency (RF) transceiver includes a reference signal source to generate a reference signal, a local RF source to generate a local RF signal and a mixed-signal phase/frequency detector to compare the reference signal to the local RF signal, and to generate a difference signal from the comparison, wherein the difference signal comprises a modulation component and an error component. The transceiver also includes a receiver front end to receive and downconverts an angle-modulated RF signal to a baseband signal, a quadrature modulator configured to angle-modulate the reference signal source with the baseband signal.

A radio frequency (RF) transceiver includes a reference signal source to generate a reference signal, a local RF source to generate a local RF signal and a mixed-signal phase/frequency detector to compare the reference signal to the local RF signal, and to generate a difference signal from the comparison, wherein the difference signal comprises a modulation component and an error component. The transceiver also includes a receiver front end to receive and downconverts an angle-modulated RF signal to a baseband signal, a quadrature modulator configured to angle-modulate the reference signal source with the baseband signal.

A trainable transceiver is provided for a vehicle for transmitting signals to a device remote from the vehicle. The trainable transceiver includes a programmable oscillator for generating a signal having a selected reference frequency; an RF transceiver that receives an RF signal during a training mode in order to learn characteristics of the received RF signal, and transmits an RF signal to the remote device in an operating mode where the transmitted RF signal includes the learned characteristics of the received RF signal, wherein the RF transceiver receives the reference frequency from the programmable oscillator and uses the reference frequency to learn the characteristics of the received RF signal and for generating the transmitted RF signal; and a controller that, during the operating mode, selects frequency control data representing a frequency and selects the selected reference frequency for the programmable oscillator as a function of the frequency control data.