An electronic device provides a detuning monitor circuit configured to detect a change in a voltage standing wave ratio (VSWR) between a radio frequency (RF) transmitter and an RF antenna relative to a predetermined VSWR baseline and a proximity detector circuit configured to adjust transmission power of a carrier wave transmitted from the RF transmitter, if the change fails to satisfy an acceptable VSWR condition. Network proximity detectors are also provided to allow coordination of antenna subsystems to comply with specific absorption rate (SAR) constraints and/or maintain/improve antenna performance.

An antenna adjusting method includes: transmitting a first broadcast message in a case that a plurality of antennae are in a SISO mode, and acquiring radiation efficiencies of the plurality of antennae; and maintaining the SISO mode in a case that the radiation efficiency of at least one of the plurality of antennae is less than a preset threshold.

Methods and apparatus are provided for detection path design for reflection coefficient estimation. In one novel aspect, a hardware-based phase estimator estimates a phase shift between the forward path signal and the reverse path signal. In one embodiment, a data selector is used to pass only signals above a magnitude threshold. In another embodiment, a modified phase unwrap algorithm stores an unwrapping correction for subsequent samples and updates the stored unwrapping correction upon processing of each sample processed. In another novel aspect, mixed hardware and software solutions are used. In one embodiment, the reference signal and the detection signals are matched such that the modulation signal interference is removed. In some embodiments, one or two power detectors and a cross-correlator are used. In yet another embodiment, two detection measurement paths are used to obtain the reflection coefficient. In one embodiment, fractional timing offset is estimated to obtain the reflection coefficient.

A method for adjusting direction of antenna for optimal radio reception, adapted to a communication device with a directional antenna. The method includes receiving a wireless signal output by a wireless signal source in a first direction at a predetermined location, and obtaining a first received power value corresponding to the first direction. A wireless signal output by the wireless signal source in a second direction is also received through the directional antenna and a second received power value corresponding to the second direction is also obtained. An optimal receiving angle according to the first received power value, the second received power value, a maximum gain value of the directional antenna, a first angle, and a second angle, is calculated and the direction of the directional antenna can be adjusted according to the optimal receiving angle.

A system for downhole frequency re-tuning includes a receiver antenna, a receiver matching network, a transmitter antenna, the transmitter antenna outputting a signal that is received at the receiver antenna, a transmitter matching network, a power amplifier providing operational power to the transmitter antenna, and a frequency sweeping system. The frequency sweeping system includes an oscillator, coupled to the power amplifier, the oscillator providing an input signal to the power amplifier to adjust power output to the transmitter antenna. The system also includes a circulator, positioned between the power amplifier and the transmitter matching network, the circulator directing the operational power to the transmitter antenna. The system further includes a reflected power meter, coupled to the circulator, the reflected power meter receiving reflected power at the transmitter antenna responsive to receiver antenna. The system also includes a control module.

Wireless communication systems and methods related radio link failure monitoring and handling in full-duplex communications are provided. A user equipment communicates, with a base station, in a full-duplex mode using a first uplink beam and a first downlink beam. The user equipment detects a beam failure of at least one of the first uplink beam or the first downlink beam. The user equipment determines whether the beam failure is associated with self-interference in the full-duplex mode. The user equipment determines, based at least in part on the determination that the beam failure is associated with the self-interference in the full-duplex mode, to refrain from declaring a radio link failure.

Aspects relate to reporting beam failure. Upon detecting a beam failure, a user equipment (UE) may transmit a beam failure recovery request to a base station. If the uplink is working, the UE may transmit the beam failure recovery request via uplink signaling (e.g., via a physical uplink control channel or a physical uplink shared channel). If the uplink is not working or if the beam failure is due to downlink quality degradation, the UE may transmit the beam failure recovery request via a random access channel (RACH) message.

An apparatus comprises a radio frequency (RF) antenna circuit; an antenna aperture tuning circuit; an antenna impedance measurement circuit; and a processor circuit electrically coupled to the tunable antenna aperture circuit and the impedance measurement circuit. The processor circuit is configured to: set the antenna aperture tuning circuit to an antenna aperture tuning state according to one or more parameters of an RF communication network; initiate an antenna impedance measurement; and change the antenna aperture tuning state to an antenna aperture tuning state indicated by the antenna impedance.

A communication device includes a donor receiver that receives a plurality of first beam of input radio frequency (RF) signals. The communication device further includes a service transmitter that transmits a plurality of second beam of RF signals in a first radiation pattern to a user equipment (UE). The communication device further includes control circuitry that detects an amount and a direction of reflected RF signals at the donor receiver. The control circuitry applies polarization to the plurality of second beam of RF signals and calibrates the polarization to minimize the reflected RF signals at the donor receiver. A second radiation pattern is generated for the plurality of second beam of RF signals and communicated to the UE based on the calibrated polarization.

A user equipment (UE) transmits reference signals for positioning while in Idle or Inactive state. While in a connected state, the UE is pre-configured with Sounding Reference Signal (SRS) resource configuration including at least one of timing adjustment (TA) and an uplink (UL) transmission spatial filter. The UE transmits positioning SRS while in Idle or Inactive mode based on the pre-configuration. The TA and UL transmission spatial filter may be updated by a serving base station using control signals or a paging message received by the UE while in in Idle or Inactive mode. The validity of the TA and UL transmission spatial filter may be monitored using expiration timers or a relative position change threshold. The reference signals transmitted may be based on a UE may Physical Random Access Channel (PRACH), which is insensitive to TA changes. A long sequence PRACH may be used for improved positioning accuracy.