Physical layer processing methods for network acquisition by remote nodes in wireless communication systems are described herein. New methods for wireless network discovery and synchronization by remote nodes are described herein that utilize spatial (e.g., antenna array) processing algorithms which may achieve enhanced functioning in challenging radio frequency environments, such as those containing interference and multipath distortion effects. These methods may include advantageous use of spatial whiteners and associated pluralities of adaptive beamformers to detect network reference and synchronization signals and estimate their parameters.

According to one aspect of the present disclosure, a baseband chip may be configured to receive a data stream associated with a channel The baseband chip may be configured to select a first anchor point from the first constellation points of the first transmission layer. The baseband chip may be configured to select a first subset of constellation points from the first constellation points and the second constellation points. The baseband chip may be configured to perform a first iteration of a recursive tree search. The baseband chip may be configured to determine a first path metric based at least in part on the first iteration of the recursive tree search operation. The baseband chip may be configured to select a second anchor point from the second constellation points of the second transmission layer. The second anchor point may be associated with a second iteration of the recursive tree search.

A wireless communication device is provided. The wireless communication device includes: a communication circuit configured to transceive a signal using a plurality of antennas; a processor configured to: detect a first interference for N resource blocks (RB) of the signal; based on the first interference being detected, perform a first whitening validation on the first interference; detect a second interference based on a result of the first whitening validation; and based on the second interference being detected, perform a second whitening validation on the second interference; and a whitening filter circuit configured to perform whitening filtering on results of the first whitening validation and the second whitening validation.

The present invention relates to a circuit structure for realizing real-time pre-distortion calibration of broadband IQ modulation, comprises a baseband generation module, for the calibration signal generator to generate two orthogonal sine cosine calibration signals respectively according to the calibration bandwidth and the order of the pre-distortion filter, and the data switch is switched to the relevant data channel; a digital-to-analog conversion module, for converting the signals into analog I and Q baseband signals; a frequency synthesis module, for generating signals in a certain frequency range; a IQ modulation module, for mixing the analog baseband signal with the local oscillator signal; an amplitude control module, for continuous adjustment of the RF signal power. The present invention also relates to a method for realizing real-time pre-distortion calibration processing of broadband IQ modulation. With the circuit structure and method of the present invention for realizing real-time pre-distortion calibration of broadband IQ modulation, the calibration process is completed locally in real time, solving the problem of frequency response error correction caused by hardware circuit performance change, so that automatic pre-distortion calibration of frequency response can be completed on site in real time.

The embodiments described herein are directed at techniques to de-correlate Bluetooth interference seen across WLAN receive antennas/space in a Bluetooth transceiver/WLAN transceiver combination device. A Bluetooth interference whitening technique may be utilized, wherein a whitening matrix is computed based on a leakage signal resulting from a training signal transmitted by the Bluetooth transceiver. The leakage signal may leak in to the WLAN transceiver and a set of attributes is calculated for each frequency the leakage signal is received on. One or more whitening matrixes are calculated based on the set of attributes for each frequency the leakage signal is received on. In response to the WLAN transceiver receiving a signal of interest, an appropriate whitening matrix from the one or more whitening matrixes is selected and is then applied to the received signal of interest to de-correlate any interference generated as a result of the Bluetooth transmission.

A wideband transmission circuit is provided. The wideband transmission circuit includes a transceiver circuit and a power amplifier circuit(s). The transceiver circuit generates a radio frequency (RF) signal(s) from a time-variant input vector and provides the RF signal(s) to the power amplifier circuit(s). The power amplifier circuit(s) amplifies the RF signal(s) based on a modulated voltage and provides the amplified RF signal(s) to a coupled RF front-end circuit (e.g., filter/multiplexer circuit). In embodiments disclosed herein, the transceiver circuit is configured to apply an equalization filter to the time-variant input vector to thereby compensate for a voltage distortion filter caused by a coupling of the power amplifier circuit(s) and the RF front-end circuit. As a result, it is possible to reduce undesired instantaneous excessive compression and/or spectrum regrowth resulting from the voltage distortion filter to thereby improve efficiency and linearity of the power amplifier circuit(s).

Methods, systems, and devices for wireless communication are described. A wireless communication device may receive multiple data streams from one or more users, associate the multiple data streams with different user groups, and identify modulation symbols for the users after reducing signal contribution from modulation symbols associated with different user groups. For example, the device may receive a signal including multiple spatial streams, partition the data streams into different user groups, and determine a set of sequences from channel characteristics associated with the respective user groups. The wireless communication device may then apply the sequences to the received signal and to values associated with the channel characteristics. Subsets of values may be selected following the application of the sequences, and from the subsets of values, the wireless communication device may identify the sets of modulation symbols associated with one or more of the user groups.

The embodiments described herein are directed at techniques to de-correlate Bluetooth interference seen across WLAN receive antennas/space in a Bluetooth transceiver/WLAN transceiver combination device. A Bluetooth interference whitening technique may be utilized, wherein a whitening matrix is computed based on a leakage signal resulting from a training signal transmitted by the Bluetooth transceiver. The leakage signal may leak in to the WLAN transceiver and a set of attributes is calculated for each frequency the leakage signal is received on. One or more whitening matrixes are calculated based on the set of attributes for each frequency the leakage signal is received on. In response to the WLAN transceiver receiving a signal of interest, an appropriate whitening matrix from the one or more whitening matrixes is selected and is then applied to the received signal of interest to de-correlate any interference generated as a result of the Bluetooth transmission.

To process received wireless signals received in a receiver, a noise and interference estimate is generated by subtracting the serving cell component from the received OFDM signal, a normalized noise signal is produced by whitening the noise and interference estimate, interference information is detected from the normalized noise signal associated with corresponding reliability information indicating reliability of the interference information, interference cancellation is performed based on the interference information, and a performance indicator indicative of an accuracy of the interference cancellation is adaptively adjusted using the reliability information.

A method and device for detecting a signal of an LTE uplink system in an interference condition. The method comprises: receiving baseband signals of M receiving antennas, and after fast Fourier transform, conducting demapping to obtain frequency-domain baseband signals; extracting a DMRS inserted in a received signal of each antenna, and then, calculating a channel gain h.sub.l,k of each receiving antenna; combining the baseband signals and the channel gains of the M receiving antennas to obtain a signal matrix Y.sub.k and a gain matrix H.sub.k; calculating an interference noise covariance matrix R.sub.k on each subcarrier; conducting interference pre-processing on a received signal on each combined subcarrier to obtain the received signal (1) and the channel gain (2) after the interference pre-processing, where D=R.sub.k.sup.−1/2; and according to (3), conducting frequency-domain balancing on the received signal after the interference pre-processing.