Marvell International Limited

Marvellworld Trade Ltd.

Yungping Hsu

Guorong Hu

Weishi Feng

Lawrence Tse

Hsiao Tang

Kedar Shirali

Ricky Cheung

Poh Boon Leong

Robert Mack

Yui Lin

Tsunglun Yu

Hsiao-Cheng Tang

Nelson Xu

Sek Kin Neng

Minko Tsai

Sandesh Goel

Ravi Narasimhan

Timothy J Donovan

Atul Salhotra

Ken Kinwah Ho

Bhaskar Nallapureddy

Chia-Chun Chung

Tam Tran

Mao Yu

Thomas B Cho

Ming Lin

Naveen-Kumar Arani

Yonghua Song

King Chun Tsai

George Chien

Rahul Kopikare

Donghong Cui

Kevin Hsiao-Cheng Tang

Systems and techniques relating to wireless signal processing. A described technique includes receiving a signal, having subcarriers, over a wireless channel formed by a number-of-receive-antennas and a number-of-transmit-antennas; determining a signal quality measure of a received signal having subcarriers, the signal quality measure being based on channel gain matrices corresponding respectively to the subcarriers of the received signal, the channel gain matrices having dimensions of the number-of-receive-antennas by the number-of-transmit-antennas; determining a channel quality measure of the received signal that measures a frequency selectivity of the wireless channel; determining a data rate of information transmission over the wireless channel based on the signal quality measure and the channel quality measure, the signal quality measure serving as a primary determinant of the data rate and the channel quality measure serves as a secondary determinant of the data rate; and transmitting information over the wireless channel in accordance with the data rate.

Adaptively determining a data rate of packetized information transmission over a wireless channel

A method and apparatus for: receiving a radio frequency (RF) signal on a first channel; determining a radio signal strength of the RF signal; performing a correlation of the RF signal with a predetermined sequence of a wireless data packet to determine whether the RF signal contains the predetermined sequence; in response to the RF signal not containing the predetermined sequence, generating an indication that the RF signal is not a wireless data packet; and determining whether the radio signal strength of the RF signal exceeds a predetermined threshold. In response to i) the radio signal strength exceeding the predetermined threshold and ii) the indication being generated: measuring a parameter associated with the RF signal; determining whether the RF signal is a radar signal based on the parameter; and changing from the first channel in response to the RF signal being determined to be a radar signal.

Radar detection and dynamic frequency selection

A network device includes a receiver that receives a first signal on a channel. A demodulator outputs demodulated data based on the first signal. A gain device, based on a change in a gain of the first signal, generates a second signal. A validating device determines whether the first signal is a valid direct sequence spread spectrum signal and based on whether the first signal is a valid direct sequence spread spectrum signal, generates a third signal. An assessment device: determines whether the demodulated data includes a predetermined header, where the predetermined header includes a predetermined sequence; determines whether the channel is busy based on the second signal, the third signal, and whether the demodulated data includes the predetermined header with the predetermined sequence; and generates a channel signal indicating whether the channel is busy. A transmitter, based on the channel signal, transmits a fourth signal on the channel.

Method and apparatus for determining whether a channel is busy

A system including a physical layer module and a control module. The physical layer module is configured to generate a first clear channel assessment for a first sub-channel of a communication channel and generate a second clear channel assessment for a second sub-channel of the communication channel. The first clear channel assessment indicates whether the first sub-channel is free or busy. The second clear channel assessment indicates whether the second sub-channel is free or busy. The control module is configured to, in response to the second sub-channel being busy, extend a duration of the second clear channel assessment by a predetermined period of time, and transmit data via (i) only the first sub-channel or (ii) both the first sub-channel and the second sub-channel based on (a) the first clear channel assessment, (b) the second clear channel assessment, and (c) the extended duration of the first clear channel assessment.

Opportunistic 40 MHz mode of transmission in wireless transmitters

A circuit includes a multiplexer, a first measurement device, and a decision device. The multiplexer is configured to receive signals from antennas, where the signals include (i) a first signal received from a first antenna of the antennas, and (ii) a second signal received from a second antenna of the antennas. The first measurement device is configured to (i) determine a first peak-to-average ratio based on the first signal, and (ii) determine a second peak-to-average ratio based on the second signal. The decision device is configured to, based on the first peak-to-average ratio and the second peak-to-average ratio, signal the multiplexer to select one of the antennas.

Apparatus and method for selecting antennas based on peak-to-average ratios of received signals

Different scan modes are provided for Bluetooth devices. In at least some embodiments, a narrowband scanning mode looks for signal energy on individual transmission frequencies at a time. By looking for signal energy rather than decoding transmitted packets, at least some of the components in a Bluetooth device can remain in an idle or rest state. A midband scanning mode looks for signal energy across multiple different frequencies at a time. Again, by looking for signal energy across multiple different frequencies rather than decoding transmitted packets, at least some of the components in a Bluetooth device can remain in an idle or rest state. A wideband scanning mode looks for signal energies across all relevant frequencies at a time. At least some embodiments enable a Bluetooth device to switch between scanning modes.

Bluetooth wideband scan mode

Systems and techniques relating to processing a signal received over a wireless channel. A technique includes adaptively determining a data rate of packetized information transmission based on both a signal quality measure of a received signal and a channel quality measure derived from the received signal, the channel quality measure being indicative of frequency selectivity in the wireless channel. An apparatus includes a channel estimator configured to be responsive to a received OFDM signal corresponding to multiple frequency tones of the channel, and configured to evaluate channel response characteristics of the frequency tones; and a channel state indicator configured to generate a channel quality measure usable along with a signal quality measure in adaptively determining a data rate of packetized information transmission, wherein the channel quality measure is generated from the channel response characteristics of the frequency tones and is indicative of frequency selectivity in the wireless channel.

Bluetooth scan modes

A transceiver including: an antenna configured to a receive a first signal transmitted on a radio frequency channel; and a peak-to-sidelobe ratio determination unit configured to generate a second signal based on a ratio, in which the ratio is based on a peak value and a sidelobe value, and the peak value and the sidelobe value are determined based on a non-correlated version of the first signal. The transceiver further includes a carrier sense unit configured to, based on the second signal, generate a third signal indicating (i) whether the radio frequency channel is busy or (ii) whether the first signal is valid.

Clear channel assessment in wireless communications

A baseband processor including an analog to digital converter configured to convert a baseband signal from an analog format into a corresponding digital format, wherein the baseband signal comprises a data packet having i) a preamble portion, ii) a header portion, and iii) a payload portion, wherein the payload portion of the data packet is in accordance with either i) a first format or ii) a second format. The baseband processor further includes a first demodulation pathway configured to recover i) the preamble portion of the data packet, ii) the header portion of the data packet, and iii) the payload portion of the data packet in response to the payload portion of the data packet being of the first format; and a second demodulation pathway configured to recover the payload portion of the data packet in response to the payload portion of the data packet being of the second format.

Phase shift keying wireless communication apparatus and method

A system includes a receiver, a processor and a decision device. The receiver receives a first signal via a first antenna, and one of the first signal and a second signal via a second antenna. The processor determines: based on the first signal as received at the first antenna, a first signal-to-noise ratio (SNR) and a first signal quality value; and based on the one of the first and second signals as received at the second antenna, a second SNR and a second signal quality value. The decision device selects one of the first and second antennas based on (i) a difference between the first SNR and the second SNR if the first SNR is greater than the second SNR, or (ii) the first signal quality value and the second signal quality value if the difference between the first SNR and the second SNR is less than a predetermined threshold.

System and method of selecting antennas based on signal-to-noise ratios and signal quality values

A system includes a signal processing module and a control module. The signal processing module receives a first clear channel assessment (CCA) signal for a first sub-channel of a communication channel, increases a pulse width of the first CCA signal by a predetermined period of time, and generates a second CCA signal. The control module receives the second CCA signal and a third CCA signal for a second sub-channel of the communication channel. The control module transmits data via one of the second sub-channel and the communication channel based on the second and third CCA signals.

A receiver is provided and includes a first amplifier configured to amplify, based on a first gain, a radio frequency signal to generate a first amplified signal. The radio frequency signal is received by the receiver on a first channel. A second amplifier generates, based on the first amplified signal and a second gain, a second amplified signal. An output circuit generates a baseband signal based on the second amplified signal. A first detection circuit compares the baseband signal to (i) a first threshold in response to the first gain being at a first level, and (ii) a second threshold in response to the first gain being at a second level. The first detection circuit generates a first detection signal in response to the comparison. A controller, in response to the first detection signal, (i) adjusts the second gain, or (ii) changes the receiver from the first channel.

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Saratoga, CA, United States of America

Yungping Hsu