Abstract: Apparatuses, methods, and systems are disclosed for preparing channel state information (“CSI”). One apparatus includes a processor and a transceiver configured to communicate with a base unit over a radio access network using at least one transmission layer and determining a total number of non-zero coefficients over a set of layers. The processor encodes the total number of non-zero coefficients by selecting a codeword from a plurality of candidate codewords in which the selected single codeword identifies the total number of non-zero coefficients to the base unit. The processor prepares CSI, where the CSI comprises the selected single codeword encoding the total number of non-zero coefficients and the transceiver transmits the CSI to the base unit.

Abstract: A range extension method and apparatus for highly directional beams are disclosed. In one aspect, a first network node that is suitable for supporting mmWave transmissions to a wireless device such as a UE may extend the range of at least one transmit beam to a UE by selecting a suitable repetition configuration that transmits repetition versions of an original signal. The first network node sends information about the repetition configuration to a second network node which can transmit a portion of the repetition configuration information to the UE using sub-6 GHz transmissions. The UE can configure a receive beam to receive mmWave communications from the first network node by using the portion of the repetition configuration information received from the second network node.

Abstract: A wireless device may receive one or more messages comprising configuration parameters for a primary cell and a secondary cell. The configuration parameters may indicate a deactivation timer for the secondary cell and a bandwidth part (BWP) inactivity timer for the primary cell. The wireless device may start the deactivation timer in response to activating the secondary cell. The wireless device may start the BWP inactivity timer in response to switching an active BWP of the primary cell. The wireless device may stop the BWP inactivity timer of the primary cell based on initiating a random-access procedure for the secondary cell. In response to the deactivation timer of the secondary cell expiring during the random-access procedure, the wireless device may restart the BWP inactivity timer of the primary cell.

Abstract: A system for bidirectional transmission in a plastic waveguide of a plurality of signals, between a first transceiver device and a second transceiver device, the plurality of signals comprising a payload carrier signal and one or more reference signals generated by one or more local oscillators on different frequencies, the first transceiver device being a power radio transceiver device, the second transceiver device being a multisignal transceiver device with no energy consumption which comprises a passive transmitter and a passive receiver.

Abstract: A free-space optical communication method is provided. The method includes generating, at a transmitter of a satellite, an optical frequency comb and a pump signal, modulating the optical frequency comb to generate a data signal and an idler signal that is a phase conjugate of the data signal, attenuating the pump signal, transmitting over free-space, from the satellite, a communication signal having the data signal, the idler signal and the pump signal, receiving from the satellite, at a receiver, the transmitted communication signal having the data signal, the idler signal, and the attenuated pump signal, amplifying, at a phase-sensitive amplifier, the data signal and the idler signal, and demodulating the data signal and the idler signal to extract data.

Abstract: Embodiments provide for guided alignment of the orientation of two wireless devices. A first wireless device is at a known position and a known orientation. A signal from a second wireless device is received via a plurality of receive elements of the first wireless device. The first wireless device measures phase differences of the signal at the plurality of receive elements, and determines locations of each of the second wireless device's transmit elements based on the differences. Based on the transmit element locations, and a known antenna layout of the second wireless device, an orientation of the second wireless device is determined. Based on differences between the determined orientation and the known orientation of the first wireless device, instructions for aligning the devices are generated. Once the devices are aligned, location estimates of a third wireless device are made by both the first wireless device and the second wireless device.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a wireless communication device may transmit a set of reference signals to an assisting device; and receive, from the assisting device, a set of feedback signals corresponding to the set of reference signals, wherein the set of feedback signals is to facilitate calibration of at least one antenna element on at least one panel associated with the wireless communication device. Numerous other aspects are provided.

Abstract: Disclosed herein is an innovative multi-layer hybrid/digital MIMO architecture that comprises single-stream or fully-connected (FC) multi-stream beamforming tiles (with RF complex-weights) in the first layer, followed by a fully connected (analog/digital) baseband layer. This architecture overcomes the complexity versus spectral-efficiency tradeoffs of existing hybrid MIMO architectures and enables MIMO stream/user scalability, superior energy-efficiency, and spatial-processing flexibility.

Abstract: Examples described herein include systems and methods which include wireless devices and systems with examples of full duplex compensation with a self-interference noise calculator that compensates for the self-interference noise generated by power amplifiers at harmonic frequencies of a respective wireless receiver. The self-interference noise calculator may be coupled to antennas of a wireless device and configured to generate the adjusted signals that compensate self-interference. The self-interference noise calculator may include a network of processing elements configured to combine transmission signals into sets of intermediate results. Each set of intermediate results may be summed in the self-interference noise calculator to generate a corresponding adjusted signal.

Abstract: A multi antenna system, comprising a plurality of transceivers for an antenna array operable for communication with wireless terminals, wherein the multi antenna system comprises a radio controller, adapted to operate a first transceiver for radio communication within a first bandwidth, wherein the first transceiver is limited by hardware to radio communication within the first bandwidth, a second transceiver adapted for radio communication within a second bandwidth selectable from a plurality of bandwidths, a radio controller adapted to operate, depending on a data rate demand, either the first transceiver or the second transceiver or both for radio communication.

Abstract: There is disclosed a method of operating a user equipment in a radio access network. The method includes transmitting acknowledgement information reporting on subject transmissions based on a HARQ codebook. The HARQ codebook indicates a bit pattern of the acknowledgement information. The bit pattern has a plurality of subpatterns, each subpattern being associated to a different subdivision of a reception time interval to which the acknowledgement information pertains. Each subpattern includes a predetermined number of bits of acknowledgement information associated to subject transmissions of the subdivision. There are also disclosed related methods and devices.

Abstract: A gate driver communication system includes a cored transformer including a primary coil and a secondary coil configured to receive power signals and uplink data signals from the primary coil; a primary side power signal generator coupled to the primary coil and configured to generate the power signals having a first frequency; a primary side data transmitter coupled to the primary coil and configured to generate the uplink data signals having a second frequency different from the first frequency; and a primary side controller configured to allocate the power signals and the uplink data signals to the primary coil according to a plurality of time slots, wherein the power signals are allocated to first time slots of the plurality of time slots and the uplink data signals are allocated to second times slots of the plurality of time slots.

Abstract: An arithmetic processing apparatus includes: a first determiner that determines, when a given learning model is repeatedly learned, an offset amount for correcting a decimal point position of fixed-point number data used in the learning in accordance with a degree of progress of the learning; and a second determiner that determines, based on the offset amount, the decimal point position of the fixed-point number data to be used in the learning. This configuration avoids lowering of the accuracy of a learning result of a learning model.

Abstract: Determining a location of a user equipment includes transmitting, by one or more processors from a network node, a first beam having a first frequency range in a first area and a second beam having a second frequency range in a second area. The first area is larger than and encompasses the second area. A request for determining the location of the user equipment is received. The one or more processors may then cause the second beam to sweep within the first area, receive a second signal from the user equipment indicating when the second beam is swept over the location of the user equipment and data related to signal measurements of the second beam at the user equipment, and determine the location of the user equipment based on a pointing direction of the second beam relative to a position of the node of the network and the received data.

Abstract: A method performed by a network node for locating a User Equipment (UE) is provided. The network node, the at least one portable network node and UE operate in a wireless communication network. The network node configures (204) the at least one portable network node to broadcast reference signals. The broadcasted reference signals trigger the UE to subsequently measure and report the quality of the respective reference signals to the network node. The network node then receives (205) subsequent measurement reports from the UE. Each measurement report comprises a current quality value of the reference signals sent by the respective at least one portable network node.

Abstract: A method for vehicular self-positioning is executed by a positioning device in a vehicle. The positioning device computes a current estimated position of the vehicle as a function of local motion data obtained from a motion sensor in the vehicle, and operates an RF module in the vehicle to receive a reference signal from one or more base stations in an environment of the vehicle, the respective base station being configured for telecommunication and being part of a 3GPP infrastructure. The positioning device further processes the reference signal to determine measured values of at least one path parameter for a selected set of multipath components, and operates a positioning algorithm, e.g. SLAM, on at least the current estimated position and the measured values to calculate a current output position of the vehicle and position information for an origin of each of the multipath components.

Abstract: Certain aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive an indication of whether to use uplink reference signals or downlink reference signals for uplink precoder determination. The UE may selectively transmit a plurality of uplink reference signals or one or more measurement reports based at least in part on the indication, wherein the one or more measurement reports are determined based at least in part on measuring a plurality of downlink reference signals. The UE may receive an indication of a precoder, of a plurality of precoders, to be used to precode an uplink communication, wherein the precoder is identified based at least in part on the plurality of uplink reference signals or the one or more measurement reports. The UE may precode the uplink communication using the precoder. Numerous other aspects are provided.

Abstract: A method includes receiving (402) a plurality of reference signals (301-303) at an antenna port of a communication device (101). Each reference signal (301-303) is sent using a corresponding precoder. The precoder is selected from a first set of precoders. The method further includes determining (403) a channel estimate based on the received plurality of reference signals (301-303), and selecting (404) a precoder from a second set of precoders based on the determined channel estimate. The second set of precoders comprises at least one precoder in addition to the precoders of the first set of precoders. The method includes sending (405) an indication (304) relating to the selected precoder.

Abstract: A method and transmission system for amplifying and providing navigation signals. The system comprises a splitter circuit configured to receive a plurality of radio frequency (RF) signals oscillating at at least two different frequencies f1 and f2. The splitter circuit is further configured to split and forward the RF signals having the f1 frequency to a first bandpass filter and the RF signals having the f2 frequency to a second bandpass filter. The system further comprises a first tunable amplifier configured to receive the RF signals from the first bandpass filter. The system further comprises a second tunable amplifier configured to receive the RF signals from the second bandpass filter at substantially the same time as the first tunable amplifier's receipt of the RF signals from the first bandpass filter. The first tunable amplifier is further configured to amplify its RF signals across a first band centered around the frequency f1.

Abstract: Disclosed are some examples of retimer circuitry, systems and methods. In some implementations, clock data recovery circuitry is coupled between a receiver and a transmitter. The clock data recovery circuitry is configured to: extract a data component from an input data signal associated with the receiver, provide the data component to the transmitter, and generate a phase control signal. Phase interpolator circuitry is coupled with the clock data recovery circuitry. The phase interpolator circuitry includes a phase interpolator configured to: receive the phase control signal, generate, based on the phase control signal, an output clock signal, and provide the output clock signal to the transmitter to track data packets of the data component.

Abstract: Embodiments provide for guided alignment of the orientation of two wireless devices. A first wireless device is at a known position and a known orientation. A signal from a second wireless device is received via a plurality of receive elements of the first wireless device. The first wireless device measures phase differences of the signal at the plurality of receive elements, and determines locations of each of the second wireless device's transmit elements based on the differences. Based on the transmit element locations, and a known antenna layout of the second wireless device, an orientation of the second wireless device is determined. Based on differences between the determined orientation and the known orientation of the first wireless device, instructions for aligning the devices are generated. Once the devices are aligned, location estimates of a third wireless device are made by both the first wireless device and the second wireless device.

Abstract: Provided is a method, performed by a user equipment (UE), of processing data in a wireless communication system, the method including: determining a format for buffer status report based on a buffer status of each of logical channel groups when the UE receiving an uplink transmission resource from a base station determines to report the buffer status to the base station; allocating, to each of the logical channel groups, a transmission resource remaining after excluding, from the uplink transmission resource, a transmission resource used for reporting the buffer status of the determined format; and re-determining the format for the buffer status report based on the buffer status of each of the logical channel groups after the allocating.

Abstract: Certain aspects of the present disclosure provide techniques for wireless communication. An exemplary method generally includes receiving an indication of a modulation and coding scheme (MCS) to use for transmitting information, wherein the indication of the MCS indicates an MCS index value corresponding to an entry in an MCS lookup table, determining, based on the MCS index value, a transport block size (TBS) to use for transmitting the information, wherein determining the TBS comprises receiving an explicit indication of the TBS to use for transmitting the information, and transmitting the information using the MCS and TBS.

Abstract: A bandgap circuit generates a substantially constant output voltage. The bandgap circuit can be integrated with other circuits of an integrated circuit and its absolute output voltage value can be calibrated to a desired voltage level. As such, the variation in absolute voltage levels which may be caused by variation in devices' parameters subject to different fabrication processes is minimized or substantially eliminated. The bandgap circuit includes a bandgap core that generates a temperature independent voltage. The bandgap circuit also includes a resistor ladder that is coupled in parallel to the bandgap core and scales the temperature independent voltage into voltage levels proportional to the temperature independent voltage. An output switch of the bandgap circuit selects the voltage level on the resistor ladder that is substantially equal to a desired voltage level. The bandgap circuit also includes a current mirror that outputs a proportional to absolute temperature current.

Abstract: A system and method for network channel selection is provided. A device includes WIFI, ZIGBEE, and BLUETOOTH communication controllers. The device's processor is configured to determine, using the communication controllers, a WIFI channel designated for communications and a first set of ZIGBEE channels designated for communications. The processor is configured to determine that a number of available BLUETOOTH channels that do not overlap the WIFI channel or any in-use ZIGBEE channels is less than a threshold number of BLUETOOTH channels required for communication using a BLUETOOTH protocol. The processor then determines the WIFI channel has a minimum duty cycle from among duty cycles of the WIFI channel and each ZIGBEE channel, determines a first BLUETOOTH channel that at least partially overlaps the WIFI channel, and causes the BLUETOOTH communication controller to transmit data using the first BLUETOOTH channel.

Abstract: Embodiments of an enhanced directional multi-gigabit (EDMG) station (STA), access point (AP), and method of communication are generally described herein. The EDMG STA may receive, from the AP, a Link Measurement Request Frame that includes a request for information for time division duplexing (TDD) rate adaptation. The EDMG STA may transmit a Link Measurement Response Frame that includes a Directional Multi Gigabit (DMG) Link Margin element that includes a Rate Adaptation Control parameter. The DMG Link Margin element may be configurable to include one or more optional fields for the TDD rate adaptation and transmit power control. The Rate Adaptation Control parameter may indicate: a number of space time streams (STSs) for which information is included in the DMG Link Margin element; and whether the DMG Link Margin element includes the one or more optional fields.

Abstract: The present disclosure relates to an electronic device, a wireless communication method, and a computer-readable medium. According to one embodiment, provided is an electronic device comprising a processing circuit and used for a user equipment side; the processing circuit is configured to control to transmit a non-precoded first uplink reference signal, receive feedback by a base station regarding the first uplink reference signal, and sending, on the basis of said feedback, a pre-coded second uplink reference signal.

Abstract: A midamble indication method includes sending, by a first device, midamble indication information to a second device. A duration of a midamble indicated by the midamble indication information is greater than or equal to a threshold. The threshold is related to a processing capability of the second device. In a midamble receiving method, the second device receives the midamble according to the indication information.

Abstract: A radio communications method includes carrying out, by a transmitter, transmission operations that include generating digital transmission signals carrying symbols to be transmitted and having a predefined time length; and transmitting a radio frequency signal carrying, in successive, non-overlapped time frames or slots having the predefined time length, the digital transmission signals generated.

Abstract: A SW used in the time transmission system in which a master node and a slave node perform transmission and reception of a precision time protocol (PTP) packet via the SW and the time of the master node is synchronized based on time information of the transmission and reception includes a delay calculator that measures an intra-device delay between input and output of the PTP packet to and from the SW, and a delay information writing unit that appends the intra-device delay measured by the delay calculator to a packet subsequent to the PTP packet, and outputs the appended packet to an output destination of the PTP packet.

Abstract: An electronic device includes: a UI; a wireless communication circuit configured to wirelessly communicate with an external electronic device by using a short-range wireless communication protocol; a processor; and a memory. The memory stores instructions, which when executed, cause the processor to receive first data from the external electronic device at a first time through a wireless communication channel by using the wireless communication circuit, receive second data from the external electronic device at a second time after the first time through the wireless communication channel by using the wireless communication circuit, compare a first reception state related to the first data and a second reception state related to the second data, and transmit, to the external electronic device, a request for change from a first mode to a second mode by using the wireless communication circuit, based on a result of the comparing.

Abstract: In one embodiment, a local control system for a rotor assembly of an apparatus includes a first actuator disposed in the rotor assembly and configured to control motion of a first controllable element in the rotor assembly. The rotor assembly is mounted to the apparatus and is rotated responsive to torque and rotational energy provided thereto. The local control system also includes a first sensor disposed in the rotor assembly and configured to provide position feedback in relation to the first controllable element. The local control system also includes a first local control computer disposed in the rotor assembly and communicably coupled to a first central control computer disposed in the apparatus external to the rotor assembly, where the first local control computer is configured to transmit a control signal to the first actuator and receive a feedback signal from the first sensor.

Abstract: In a radar system, a cancellation circuit is described for compensating for the effects of spillover between each transmitter and a receiver. The cancellation circuit is configured for applying cancellation signals to the receiver which are generated in a cancellation filter utilizing a primary impulse response characteristic corresponding to the spillover, a signal to be transmitted from each transmitter in the radar system, and a range profile output from the receiver. The cancellation circuit may also include a secondary impulse response characteristic module and a dithering module to improve the sensitivity of the receiver.

Abstract: A method for determining a carrier center frequency in a wireless communications system and apparatus are provided. The method includes: determining, a carrier center frequency used by a base station and UE to communicate, according to a frequency band starting frequency, and absolute radio frequency channel number, a frequency band offset, and a relative radio frequency channel number. According to this application, a time for searching for a cell by a terminal can be reduced, power consumption of the terminal can be reduced, and a battery life can be extended.

Abstract: This application relates to methods and apparatus for transfer of multiple digital data streams, especially of digital audio data over a single communications link such as a single wire. The application describes audio interface circuitry comprising a pulse-length-modulation (PLM) modulator. The PLM is responsive to a plurality of data streams (PDM-R, PDM-L), to generate a series of data pulses (PLM) with a single data pulse having a rising and falling edge in each of a plurality of transfer periods defined by a first clock signal (TCLK). The timing of the rising and falling edge of each data pulse is dependent upon a combination of the then current data samples from the plurality of data streams. The duration and position of the data pulse in the transfer window in effect defines a data symbol encoding the data. Circuitry for receiving and extracting the data is also disclosed.

Abstract: The systems and methods discussed herein utilized a wireless or wired transceiver having a transmitter and a receiver. The transceiver is configured to reduce distortion contributions associated with echo cancelling. The transmitter provides a replica signal and a transmit signal. The replica signal and the transmit signal can be provided using a common switch.

Abstract: An apparatus for processing a received radio signal includes at least one processor and at least one memory. The at least one memory storing computer program code. The at least one memory and the computer program code being configured to, with the at least one processor, cause the apparatus to at least in part perform processing (received radio signal data with first and second signal processing chains, which respectively include first and second processing modules configured to respectively determine first output and an estimation of the first output data, and determine second output data using a neural network based on the estimation; updating parameters of the neural network based on the first output data and the second output data; and after the updating, processing the received radio signal data with the second signal processing chain, without applying the first processing module.

Abstract: Methods, apparatus, systems and articles of manufacture to compensate radar system calibration are disclosed. A radio-frequency (RF) subsystem having a transmit channel, a receive channel, and a loopback path comprising at least a portion of the transmit channel and at least a portion of the receive channel, a loopback measurer to measure a first loopback response of the RF subsystem for a first calibration configuration of the RF subsystem, and to measure a second loopback response of the RF subsystem for a second calibration configuration of the RF subsystem, and a compensator to adjust at least one of a transmit programmable shifter or a digital front end based on a difference between the first loopback response and the second loopback response to compensate for a loopback response change when the RF subsystem is changed from the first calibration configuration to the second calibration configuration.

Abstract: An apparatus for generating a data signal comprises a processing circuit configured to generate the data signal, the data signal comprising a sequence of a first signal edge of a first type, a second signal edge of a second type, and a third signal edge of the first type, the first signal edge and the second signal edge being separated by a first time period corresponding to first data to be transmitted, and the second signal edge and the third signal edge being separated by a second time period corresponding to second data to be transmitted. An output interface circuit is configured to output the data signal.

Abstract: Embodiments of the present disclosure provide a method, apparatus and computer program products for DC offset degradation. A method implemented in a massive multi-input multi-output (MIMO) system, which comprises a plurality of receiver branches, includes receiving a radio frequency (RF) signal in the plurality of receive branches. The method further includes configuring different local frequencies of a plurality of local oscillators respectively in the plurality of receiver branches according to a carrier frequency of the RF signal, to enable direct current (DC) offsets in the plurality of receiver branches to be distinguishable from each other in frequency.

Abstract: Aspects of the present disclosure provide techniques and apparatus for wireless communication. In one aspect, a method is provided which may be performed by a wireless device such as a user equipment (UE). The method generally includes: receiving signaling on a plurality of carriers, and dynamically assigning non-linear interference cancellation (NLIC) to a subset of the plurality of carriers based on at least one criteria, wherein the NLIC is available to a number of carriers that is less than a total number of carriers in the plurality of carriers.

Abstract: A system includes a Zero IF transmitter having a mixer and a programmable gain stage. The Zero IF transmitter also includes an intermediate stage between the mixer and the programmable gain stage, wherein the intermediate stage is configured to decouple the mixer and the programmable gain stage.

Abstract: Sharing of frequency generator settings in a network are disclosed. In a particular implementation, a method of wireless communication includes determining, by a user equipment (UE), a first frequency setting for a frequency generator of a UE. The first frequency setting is associated with a first frequency. The method includes modifying the first frequency setting to generate a second frequency setting for the frequency generator. The second frequency setting is associated with a second frequency that is different from the first frequency. The method also includes generating a message that indicates the second frequency setting. The method further includes transmitting the message from the UE to a base station.

Abstract: Devices and methods related to wideband multiplexer for radio-frequency (RF) applications. In some embodiments, a method for multiplexing radio-frequency (RF) signals can include providing a common path to receive a plurality of RF signals. The method can also include processing a first RF signal through a first path such that the processed first RF signal is routed to the common path, the processing of the first RF signal including band-passing the first RF signal for a frequency band BX. The method can further include processing a second RF signal through a second path such that the processed second signal is routed to the common path, the processing of the second RF signal including band-stopping the second RF signal for the frequency band BX such that the common path includes a wideband response that includes the frequency band BX and one or more other frequency bands.

Abstract: Described examples provide for digital communication circuits and systems that implement digital pre-distortion (DPD). In an example, a system includes a DPD circuit configured to compensate an input signal for distortions resulting from an amplifier. The DPD circuit includes an infinite impulse response (IIR) filter configured to implement a transfer function. The IIR filter includes a selection circuit configured to selectively output a selected parameter. The transfer function is based on the selected parameter.

Abstract: Consistent with the present disclosure a network is provided that includes a primary node and a plurality of secondary nodes. The primary node, as well as each of the secondary nodes, includes a laser that is “shared” between the transmit and receive sections. That is, light output from the laser is used for transmission as well as for coherent detection. In the coherent receiver, the frequency of the primary node laser is detected and, based on such detected frequency, the frequency of the secondary node laser is adjusted to detect the received information or data. Such frequency detection also serves to adjust the transmitted signal frequency, because the laser is shared between the transmit and receive portions in each secondary receiver. Light output from the primary node laser, which is also shared between transmit and receive portions in the primary node, is thus also set to a frequency that permits detection of each of the incoming optical signals by way of coherent detection.

Abstract: Embodiments of the present disclosure provide a method, a device and a computer readable medium for communication based on a multi-TRP codebook. According to a method for communication, a terminal device measures downlink channel conditions related to a plurality of network devices in communication with the terminal device. The terminal device selects a precoding matrix from a codebook based on the downlink channel conditions, elements in a column of the codebook represent respective beam sets for the plurality of network devices, and the precoding matrix indicates respective beams for the plurality of network devices. The terminal device transmits an index of the precoding matrix to at least one of the plurality of network devices. The embodiments of the present disclosure enable multi-TRP PMI feedback based on the proposed multi-TRP codebook.

Abstract: This application provides antenna panel training methods and apparatuses. One method includes: determining, by a network device, configuration information that comprises information about a reference signal resource set for training an antenna panel of a terminal device; and sending, by the network device, the configuration information to the terminal device.

Abstract: A method, providing an oscillator output signal to reference inputs of a PLL and an output clock circuit; providing a first divisor value to a control input of the PLL to regulate a closed loop that includes a physics cell, a receiver, and the PLL; providing a second divisor value to a control input of the output clock circuit to control an output frequency of an output clock signal; shifting the first divisor value in a first direction to cause a perturbation in the closed loop; shifting the second divisor value in an opposite second direction to counteract a response of the closed loop to the perturbation and to regulate the output frequency of the output clock signal; and based on the receiver output signal, analyzing the response of the closed loop to the perturbation.

Abstract: An operating method of a wireless communication apparatus including a plurality of antennas and receiving a data signal through a downlink channel from a base station includes: calculating a plurality of estimated energy efficiencies under a plurality of reception conditions of the wireless communication apparatus in accordance with prior information regarding a number of transmission ranks and a number of receiving antennas to be used for receiving the data signal; and generating channel state information by using the calculated estimated energy efficiencies and determining the number of receiving antennas.