Methods, systems, and devices for wireless communications are described. Generally, the described techniques provide for activating antenna groups at a user equipment (UE) for communications with a base station. The UE may receive an indication of at least one active antenna group for communications with the base station, and the UE may map one or more layers of an uplink message to the at least one active antenna group. The UE may then transmit the one or more layers of the uplink message using the at least one active antenna group based on the mapping. In some cases, the UE may transmit a capability report to the base station indicating one or more antennas in each antenna group in a set of antenna groups at the UE, and the base station may activate the at least one active antenna group from the set of antenna groups.

The present invention discloses an adaptive parameter adjustment method for a hybrid precoding millimeter-wave transmission system. The method includes the following step: interacting between a transmitter and a receiver for a number of radio frequency chains that need to be established. The receiver calculates, according to a received signal power at the time of established a different number of radio frequency chains and a total power consumption at the time of established the different number of radio frequency chains, the number of the radio frequency chains that need to be established. According to the present invention, under a condition of balancing power consumption and a rate, a number of radio frequency chains that need to be established is adaptively selected, so as to optimally configure power consumption and a transmission rate in a millimeter-wave transmission system.

Disclosed are an electronic device and a method of transmitting a wireless signal thereof. The electronic device includes: a housing; a first antenna configured to form a first part of the housing; a second antenna configured to form a second part of the housing; and at least one processor including a first transmission terminal and a second transmission terminal connected to the first antenna and the second antenna, respectively, wherein the at least one processor is further configured to identify a strength of at least one of a transmission signal and a reception signal when transmission of a wireless signal is requested, and control at least one of a phase and a strength of wireless signals output through the first transmission terminal and the second transmission terminal according to a result of the identification. Various other embodiments are possible.

Certain aspects involve an interface device for a distributed antenna system (DAS). In some aspects, the interface device can include an interface, a power detector, and a processor. The interface can include one or more ports for communicatively coupling the interface device to a base station and a switch that is switchable between first and second configurations. The first configuration connects a port to a downlink path of the DAS, and the second configuration connects the port to a signal reflection path. The processor can switch the switch between the first and second configurations based on a signal power measured by the power detector at the port. In other aspects, the interface device can include additional ports and termination loads. The processor can cause a signal path to be connected to a termination load instead of a port based on the port being disconnected from a unit of the DAS.

An embodiment relates to a vehicular distributed antenna system operating in a wireless communication system, the vehicular distributed antenna system comprising: a plurality of distributed units including RF antennas; and a central unit for controlling the plurality of distributed units, wherein, in a case of receiving a configuration of a power sleep mode from the central unit, the plurality of distributed units store final configuration parameter information; and in a case of receiving a configuration of a power activation mode from the central unit, the plurality of distribution units use the stored final configuration parameter information when a storage parameter use mode is configured, and receive new configuration parameter information when the storage parameter use mode is not configured.

An Audio/Video (A/V) transmitting device may include a Radio Frequency (RF) transmitting module configured to transmit a compressed RF packet to an RF receiving module of an A/V receiving device, the RF transmitting module including a plurality of transmitting antennas, and a processor configured to obtain radio performance between the RF transmitting module and the RF receiving module and, when the obtained radio performance satisfies a preset radio performance, sequentially turn off one or more transmitting antennas among the plurality of transmitting antennas.

Systems, methods, and computer-readable media herein modify the configuration of one or more antenna elements of an antenna array based on signal quality information associated with one or more UE devices. The signal quality information of the UE devices can be analyzed by a base station and the base station can respond to the change in signal quality of the UE devices by modifying one or more antenna elements from a first mapping to a second mapping to improve the quality of transmissions between the UE devices and a base station.

Multiple-Input Multiple-Output (MIMO) transmitters, receivers and transceivers are disclosed, as well as other associated devices, systems and methods. In particular, aspects and embodiments of the disclosure relate to MIMO transmitters, receivers and transceivers implemented as modules of relay devices for signals transmitted to and/or from base-stations and/or mobile-stations, in particular when such devices are implemented on mobile and/or aerial vehicles, and in particular for transmitting, receiving and/or forwarding wireless communication signals at frequencies in what is termed the millimeter-wave band. In such devices, a power control unit is configured to determine an energy availability measure and/or a power demand measure and, in response, cause a switching unit to connect a plurality of RF chains to a plurality of antenna elements in different states.

Certain aspects involve an interface device for a distributed antenna system (DAS). In some aspects, the interface device can include an interface, a power detector, and a processor. The interface can include one or more ports for communicatively coupling the interface device to a base station and a switch that is switchable between first and second configurations. The first configuration connects a port to a downlink path of the DAS, and the second configuration connects the port to a signal reflection path. The processor can switch the switch between the first and second configurations based on a signal power measured by the power detector at the port. In other aspects, the interface device can include additional ports and termination loads. The processor can cause a signal path to be connected to a termination load instead of a port based on the port being disconnected from a unit of the DAS.

Antenna structures and methods of operating the same of an electronic device are described. One apparatus includes an antenna element that is self-resonant at a first frequency in a first mode and self-resonant at a second frequency in a second mode. A radio frequency (RF) is coupled between the antenna element and a ground plane. A RF circuit, coupled to the antenna element via an RF feed, is operable to control the RF switch to switch the antenna element between the first mode and the second mode. The RF circuit is operable to cause the antenna element to radiate or receive electromagnetic energy in a first radiation pattern in the first mode and to radiate or electromagnetic energy in a second radiation pattern in the second mode.