In embodiments, apparatuses, methods, and storage media may be described for reducing the overhead associated with the transmission of channel training signals from an eNodeB (eNB) of a wireless network. Specifically, the eNB may receive feedback from a user equipment (UE) regarding the received signal energy of a first and second beamformed signal produced with a first and second beamforming vector, respectively. The eNB may identify, based on the feedback of the received signal energy, a signal subspace and a null subspace. The eNB may then transmit a channel training signal to the signal subspace.

Generally, this disclosure provides devices, systems and methods for provisioning of wireless local area network (WLAN) traffic load measurements to third generation partnership project 3GPP wireless cellular networks. A WLAN element manager (EM) may include a polling module to poll a WLAN access point (AP), the polling to request traffic load data from the WLAN AP; a timer module to trigger the polling module to poll at periodic intervals; a logging module to receive and log the requested traffic load data; and an integration reference point (IRP) agent including a reporting module to generate a traffic load report for transmission to a network manager (NM), the traffic load report based on the logged traffic load data.

Generally, this disclosure provides devices, systems and methods for provisioning of wireless local area network (WLAN) traffic load measurements to third generation partnership project 3GPP wireless cellular networks. A WLAN element manager (EM) may include a polling module to poll a WLAN access point (AP), the polling to request traffic load data from the WLAN AP; a timer module to trigger the polling module to poll at periodic intervals; a logging module to receive and log the requested traffic load data; and an integration reference point (IRP) agent including a reporting module to generate a traffic load report for transmission to a network manager (NM), the traffic load report based on the logged traffic load data.

Method and apparatus for antenna calibration have been disclosed. A radio unit (510) is provided. The radio unit (510) may comprise: a plurality of transmit/receive (TX/RX) paths; a plurality of radio frequency (RF) ports (512) connected with the plurality of TX/RX paths; and a coupling unit (516), coupled with the plurality of TX/RX paths and configured to inject an uplink (UL) calibration signal (550) into at least one of the plurality of TX/RX paths and extract a downlink (DL) calibration signal (540) from at least one of the plurality of TX/RX paths. A normal TX/RX path may be reused both for antenna calibration and antenna supervision. Thus, a low cost hardware solution for antenna calibration is provided. An AIR base station (500) comprising such radio unit (510) is also provided.

Method and apparatus for antenna calibration have been disclosed. A radio unit (510) is provided. The radio unit (510) may comprise: a plurality of transmit/receive (TX/RX) paths; a plurality of radio frequency (RF) ports (512) connected with the plurality of TX/RX paths; and a coupling unit (516), coupled with the plurality of TX/RX paths and configured to inject an uplink (UL) calibration signal (550) into at least one of the plurality of TX/RX paths and extract a downlink (DL) calibration signal (540) from at least one of the plurality of TX/RX paths. A normal TX/RX path may be reused both for antenna calibration and antenna supervision. Thus, a low cost hardware solution for antenna calibration is provided. An AIR base station (500) comprising such radio unit (510) is also provided.

A system for enhanced linearity mixing includes an input-source signal coupler; a local oscillator (LO) signal coupler; a primary mixer that combines, via heterodyning, the primary-mixer-input signal and the primary-mixer-LO signal to generate a primary-mixer-output signal; a distortion-source mixer that combines, via heterodyning, the distortion-mixer-input signal and the distortion-mixer-LO signal to generate a distortion-mixer-output signal; and an output signal coupler that combines the primary-mixer-output signal and the distortion-mixer-output signal to generate an output signal with reduced non-linearity.

A system for enhanced linearity mixing includes an input-source signal coupler; a local oscillator (LO) signal coupler; a primary mixer that combines, via heterodyning, the primary-mixer-input signal and the primary-mixer-LO signal to generate a primary-mixer-output signal; a distortion-source mixer that combines, via heterodyning, the distortion-mixer-input signal and the distortion-mixer-LO signal to generate a distortion-mixer-output signal; and an output signal coupler that combines the primary-mixer-output signal and the distortion-mixer-output signal to generate an output signal with reduced non-linearity.

A radio frequency module includes: a module board that includes a first principal surface and a second principal surface on opposite sides of the module board; a power amplifier; and a first circuit component. The power amplifier includes: a first amplifying element; a second amplifying element; and an output transformer that includes a primary coil and a secondary coil. An end of the primary coil is connected to an output terminal of the first amplifying element, another end of the primary coil is connected to an output terminal of the second amplifying element, an end of the secondary coil is connected to an output terminal of the power amplifier, the first amplifying element and the second amplifying element are disposed on the first principal surface, and the first circuit component is disposed on the second principal surface.

A filter circuit includes a first switch circuit that exclusively connects a first common terminal to either of a first selection terminal and a second selection terminal; a first signal terminal that is connected to the first selection terminal and that is for communicating a first communication signal belonging to a first frequency range, which is a frequency range of a first communication band; a second signal terminal that is connected to the second selection terminal and that is for communicating a second communication signal belonging to a second frequency range, which is the frequency range of a second communication band and which is at least partially overlapped with the first frequency range; and a first band pass filter one end of which is connected to the first common terminal and which uses both the first frequency range and the second frequency range as pass bands.

A filter circuit includes a first switch circuit that exclusively connects a first common terminal to either of a first selection terminal and a second selection terminal; a first signal terminal that is connected to the first selection terminal and that is for communicating a first communication signal belonging to a first frequency range, which is a frequency range of a first communication band; a second signal terminal that is connected to the second selection terminal and that is for communicating a second communication signal belonging to a second frequency range, which is the frequency range of a second communication band and which is at least partially overlapped with the first frequency range; and a first band pass filter one end of which is connected to the first common terminal and which uses both the first frequency range and the second frequency range as pass bands.