Qualcomm Incorporated

Qualcomm Atheros Inc.

Bemini Hennadige Janath Peiris

Ning Zhang

Sundar G Sankaran

Chi-Lin Su

A mechanism for controlling transmit power associated with a plurality of transmit chains of a beamforming transceiver system. A plurality of beamforming steering matrices associated with a plurality of subcarriers of an RF signal received at the transceiver system are generated. A maximum transmit power associated with each of the plurality of transmit chains of the transceiver system is calculated. A power scaling factor for each of the plurality of transmit chains is determined based, at least in part, on the beamforming steering matrices and the maximum transmit power associated with each transmit chain. At least one of the power scaling factors is applied to the plurality of transmit chains to control the transmit power associated with each transmit chain.

Transmitter beamforming power control

A mechanism for processing beamforming steering matrices in a transceiver system. A plurality of beamforming steering matrices associated with a plurality of subcarriers of an RF signal received at the transceiver system are generated. The beamforming steering matrices are compressed and stored. The beamforming steering matrices may also be grouped or sub-sampled prior to being stored. The beamforming steering matrices are decompressed and ungrouped before being applied to data to be transmitted. Prior to ungrouping the beamforming steering matrices, a phase difference between corresponding beamforming steering vectors of consecutive beamforming steering matrices is determined. Phase rotation is performed on the corresponding beamforming steering vectors based on the determined phase difference associated with the corresponding beamforming steering vectors to improve phase continuity between consecutive beamforming steering matrices.

Transmitter beamforming steering matrix processing and storage

A method and device for concurrently transmitting a Wi-Fi signal and a Bluetooth signal via a common power amplifier and antenna. A first set of values indicative of transmission power levels of a Wi-Fi signal and a corresponding set of values indicative of transmission power levels of a BT signal are stored in a table. Information about activities pertaining to the BT signal including a value of a transmission power level of the BT signal is received. Based on the received value of the transmission power level of the BT signal, a corresponding value of a transmission power level of the Wi-Fi signal may be looked up from the table. Transmission of one or more of the Wi-Fi or BT signals may be controlled, based on at least one of the received information or the looked-up value of the transmission power level of the Wi-Fi signal.

Concurrent transmission of Wi-Fi and Bluetooth signals

Provided is a radio-frequency (RF) power amplifier system that includes a look-up table (LUT), populated with values indicative of predistortion information that is stored in a memory location, and a transmit path that includes a predistorter to receive a transmission signal (TX) and output a predistorted transmission (TX) signal, wherein the predistorted transmission signal is compensated for distortion of the transmit path, and wherein the predistorter outputs the predistorted TX signal based on the values indicative of predistortion information populated in the look-up table. The transmit path also includes a digital to analog converter (DAC) configured to receive the predistorted TX signal from the predistorter and output an analog predistorted transmission (TX) signal, and a power amplifier configured to amplify the analog predistorted TX signal.

Power amplifier linearization system and method

Predistortion may be employed to avoid distortion in the output of a power amplifier (PA) in a transmitter, while maintaining transmit power. An active transmission signal, instead of test tones, may be used for training a predistorter for the PA, and for the entire analog transmit path of the transmitter, via a loopback path from the output of the PA to the input of a receiver path. The transmitter may include an upconverter, and the receive path may include a downconverter, which may therefore both be included in the loopback path, helping eliminate phase noise. The predistortion training may incorporate fractional timing correction, to properly align the amplified version of the original TX signal received via the loopback path with the original TX signal. The transfer function of the PA may be estimated as a polynomial function, obtaining the coefficients of the polynomial function using adaptation techniques according to one of a number of possible different methods, e.g. through curve fitting using a least mean square (LMS) algorithm.

Power amplifier linearization using digital predistortion

A calibration mechanism is disclosed for performing I/Q mismatch calibration operations in a wireless communication device comprising a receiver unit and a transmitter unit. During an I/Q mismatch calibration mode, a first signal and a second signal are provided from the transmitter unit to the receiver unit via a loopback path coupled between the transmitter and receiver units. A phase shift is added to the second signal that is provided to the receiver unit. A first set of I/Q measurements is determined from the first signal and a second set of I/Q measurements is determined from the second signal with the added phase shift. Transmitter and receiver I/Q mismatch parameters are calculated based on the first and second sets of I/Q measurements. The receiver and transceiver I/Q mismatch parameters are used to compensate for I/Q mismatch at the receiver and transmitter units, respectively.

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Sunnyvale, CA, United States of America

Bemini Hennadige Janath Peiris