摘要:
Various methods and corresponding active interference cancellation units are described. These methods and units can perform active interference cancellation in a system including multiple radios. Notably, signals from a first radio can be received as interference at a second radio. The described methods and units can provide interference conditioning, which manipulates an interference reference of the interference at the first radio to approximate an interference observed at the second radio. After tuning of the interference conditioning, the interference can be removed.
摘要:
A method of performing dynamic sounding in a wireless communication device includes determining whether to perform sounding based on an age of current channel state information (CSI). An achievable throughput can be recorded as a reference throughput after performing the sounding. A current achievable throughput can be compared with the reference throughput. A CSI timestamp can be reset when the current throughput is above the reference throughput by a first predetermined amount, thereby prolonging a lifespan of the current CSI. The CSI timestamp can be reduced when the current throughput is below the reference throughput by a second predetermined amount, thereby reducing the lifespan of the current CSI.
摘要:
A wireless transmitter can include a plurality of bandwidth modules, each bandwidth module processing data based on a predetermined frequency band. In one embodiment, such a wireless transmitter can include encoding components for receiving transmit data and generating encoded data. A multiple-input multiple-output (MIMO) stream parser can receive the encoded data and generate a plurality of MIMO streams. A first module parser coupled to a first MIMO stream can generate a first plurality of partial MIMO streams. A first bandwidth module can include a first interleaver that interleaves bits of the first partial MIMO stream and generates first interleaved data. A second bandwidth module can include a second interleaver that interleaves bits of the second partial MIMO stream and generates second interleaved data. A first inverse fast Fourier transform (IFFT) unit can combine and process the first and second interleaved data and generate a first transmission MIMO stream.
摘要:
A process for determining when sounding packets are to be triggered and transmitted in a wireless beamforming system is disclosed. In one embodiment, a timer is programmably set to adapt to the operating environment. Whenever the timer elapses, a sounding packet is triggered and the timer resets. In another embodiment, the sounding packet is triggered by comparing measured correlations of channel characteristics against a programmable correlation threshold. If a measured correlation falls below the correlation threshold, this indicates that the channel has undergone a relatively large change. In response, a new sounding packet is triggered to update the beam steering matrix. Otherwise, the previous beam steering matrix is still used. Thereby, sounding packets are expeditiously triggered to keep the beam steering matrix updated with minimal impact to the over-the-air bandwidth.
摘要:
A fast diversity technique using either an EESM or a capacity computation can determine antenna selection in a wireless communication device. A fast Fourier transform (FFT) for the EESM/capacity computation can be performed with consecutive samples of a single symbol period of a short training field (STF) of a packet received by each antenna. The effective signal-to-noise ratio (SNR) for each antenna can be calculated using the results of the EESM or capacity computation. The antenna with the highest effective SNR is selected.
摘要:
In a multiple-input, multiple-output system, the frequency of transmitted signals can be partitioned into some number of frequency bins. During an exchange of sounding signals, a first station can monitor the quality of the signals to select a second station that is qualified to participate in a calibration procedure. The first station can generate a first set of channel characteristics for a particular frequency bin based on the sounding signal it receives from the second station. The first station also receives channel state information from the second station which can be used to generate a second set of channel characteristics for the particular frequency bin. Then, the selected subsets of the first and second sets can be manipulated in order to determine a set of correction values for that frequency bin as well as for other frequency bins.
摘要:
A wireless transmitter can include a plurality of bandwidth modules, each bandwidth module processing data based on a predetermined frequency band. In one embodiment, such a wireless transmitter can include encoding components for receiving transmit data and generating encoded data. A multiple-input multiple-output (MIMO) stream parser can receive the encoded data and generate a plurality of MIMO streams. A first module parser coupled to a first MIMO stream can generate a first plurality of partial MIMO streams. A first bandwidth module can include a first interleaver that interleaves bits of the first partial MIMO stream and generates first interleaved data. A second bandwidth module can include a second interleaver that interleaves bits of the second partial MIMO stream and generates second interleaved data. A first inverse fast Fourier transform (IFFT) unit can combine and process the first and second interleaved data and generate a first transmission MIMO stream.
摘要:
A fast diversity technique using either an EESM or a capacity computation can determine antenna selection in a wireless communication device. A fast Fourier transform (FFT) for the EESM/capacity computation can be performed with consecutive samples of a single symbol period of a short training field (STF) of a packet received by each antenna. The effective signal-to-noise ratio (SNR) for each antenna can be calculated using the results of the EESM or capacity computation. The antenna with the highest effective SNR is selected.
摘要:
The antenna configurations of a wireless communications system including a beamformer and beamformee may be changed. In an improved technique for triggering a sounding packet, notification of an antenna re-configuration, either at the beamformer or the beamformee can be quickly used by the beamformer to trigger the sounding packet. In one embodiment, the beamformee can perform its own computations to determine a changing channel. In this embodiment, once a changing channel is detected, the beamformee can notify the beamformer to trigger the sounding packet.
摘要:
Joint transmit error (i.e., carrier leak and I/Q mismatch) calibration can be implemented in a transmitter unit in a wireless device. DC signals can be superposed onto digital complex tone signals to generate calibration signals for joint transmit error calibration. The calibration signals may also be phase shifted and/or pre-distorted with digital I/Q phase to yield distinct calibration measurements that can be used for joint transmit error calibration. Digital scaling can be applied at the transmitter unit in accordance with a transmitter gain setting to maintain a constant receiver gain setting. At a receiver unit of the wireless device, the DC signals can be separated from the digital complex tone signals for transmit error calibration. Such a joint transmit error calibration can minimize calibration time, reduce the number of computations required for transmit error calibration, improve the accuracy of the transmit error calibration, and improve performance of the wireless device.