Patents by Inventor Qifan Chen
Qifan Chen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20240007241Abstract: This disclosure provides methods, devices and systems for increasing the transmit power of wireless communication devices operating on power spectral density (PSD)-limited wireless channels. Some implementations more specifically relate to LTF designs that support distributed transmissions. In some aspects, a transmitting device may obtain a sequence of values representing an LTF of a PPDU and may map the sequence of values to a number (N) of noncontiguous subcarrier indices of a plurality of subcarrier indices spanning a wireless channel according to a distributed tone plan. In some implementations, the transmitting device may modulate the sequence of values on N tones, representing a logical RU, and map the N tones to the N noncontiguous subcarrier indices, respectively. In some other implementations, the sequence of values may be obtained based on relative locations of the N noncontiguous subcarrier indices in the wireless channel.Type: ApplicationFiled: May 24, 2023Publication date: January 4, 2024Inventors: Lin YANG, Bin TIAN, Qifan CHEN, Youhan KIM
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Patent number: 11838227Abstract: This disclosure provides methods, devices and systems for increasing the transmit power of wireless communication devices operating on power spectral density (PSD)-limited wireless channels. Some implementations more specifically relate to pilot tone designs that support distributed transmission. A transmitting device may modulate a physical layer convergence protocol (PLCP) protocol data unit (PPDU) on a number (M) of tones representing a logical RU associated with the legacy tone plan and may further map the M tones to M noncontiguous subcarrier indices associated with a wireless channel. The transmitting device may transmit the PPDU, over the wireless channel, with a number (N) of pilot tones each having a respective location relative to the M tones as mapped to the M noncontiguous subcarrier indices. In some implementations, the relative locations of the N pilot tones may be different than relative locations of a number (K) of pilot tones associated with the logical RU.Type: GrantFiled: July 30, 2021Date of Patent: December 5, 2023Assignee: QUALCOMM IncorporatedInventors: Lin Yang, Bin Tian, Youhan Kim, Qifan Chen
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Patent number: 11711184Abstract: This disclosure provides methods, devices and systems for increasing the transmit power of wireless communication devices operating on power spectral density (PSD)-limited wireless channels. Some implementations more specifically relate to LTF designs that support distributed transmissions. In some aspects, a transmitting device may obtain a sequence of values representing an LTF of a PPDU and may map the sequence of values to a number (N) of noncontiguous subcarrier indices of a plurality of subcarrier indices spanning a wireless channel according to a distributed tone plan. In some implementations, the transmitting device may modulate the sequence of values on N tones, representing a logical RU, and map the N tones to the N noncontiguous subcarrier indices, respectively. In some other implementations, the sequence of values may be obtained based on relative locations of the N noncontiguous subcarrier indices in the wireless channel.Type: GrantFiled: October 4, 2021Date of Patent: July 25, 2023Assignee: QUALCOMM IncorporatedInventors: Lin Yang, Bin Tian, Qifan Chen, Youhan Kim
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Publication number: 20230124579Abstract: This disclosure provides methods, devices and systems for increasing the transmit power of wireless communication devices operating on power spectral density (PSD)-limited wireless channels. Some implementations more specifically relate to short training field (STF) designs and signaling that support distributed transmissions. A transmitting device that transmits data on a distributed resource unit (dRU) may transmit an STF sequence over a spreading bandwidth of the dRU according to an existing STF tone plan. Each STA allocated a dRU for transmission in a trigger-based (TB) physical layer convergence protocol (PLCP) protocol data unit (PPDU) maps its STF sequence to one or more spatial streams and may apply one or more global cyclic shift delays (CSDs) to the STF sequence mapped to the one or more spatial streams, respectively. As such, different global CSDs may be assigned to different STAs so that each STA transmits its STF sequence with different amounts of delay.Type: ApplicationFiled: October 15, 2021Publication date: April 20, 2023Inventors: Lin YANG, Bin Tian, Youhan Kim, Qifan Chen
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Publication number: 20230104295Abstract: This disclosure provides methods, devices and systems for increasing the transmit power of wireless communication devices operating on power spectral density (PSD)-limited wireless channels. Some implementations more specifically relate to LTF designs that support distributed transmissions. In some aspects, a transmitting device may obtain a sequence of values representing an LTF of a PPDU and may map the sequence of values to a number (N) of noncontiguous subcarrier indices of a plurality of subcarrier indices spanning a wireless channel according to a distributed tone plan. In some implementations, the transmitting device may modulate the sequence of values on N tones, representing a logical RU, and map the N tones to the N noncontiguous subcarrier indices, respectively. In some other implementations, the sequence of values may be obtained based on relative locations of the N noncontiguous subcarrier indices in the wireless channel.Type: ApplicationFiled: October 4, 2021Publication date: April 6, 2023Inventors: Lin YANG, Bin TIAN, Qifan CHEN, Youhan KIM
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Publication number: 20230069075Abstract: This disclosure provides methods, devices and systems for distributed transmission of short training fields in a power spectral density limited frequency band. In one aspect, a device receives a distributed resource unit (dRU) assignment for transmission of a dRU portion of a physical layer protocol data unit (PPDU); determines a spatial stream global cyclic shift delay (CSD) index for an short training field (STF) of the dRU portion of the PPDU; and transmits, based on the spatial stream global CSD index, the EHT of the dRU portion of the PPDU across a dRU spreading bandwidth associated with the dRU assignment using a tone plan and sequence corresponding to a regular resource unit (rRU) transmission mode.Type: ApplicationFiled: August 13, 2021Publication date: March 2, 2023Inventors: Lin YANG, Bin TIAN, Youhan KIM, Qifan CHEN
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Publication number: 20230048884Abstract: This disclosure provides methods, devices and systems for increasing the transmit power of wireless communication devices operating on power spectral density (PSD)-limited wireless channels. Some implementations more specifically relate to pilot tone designs that support distributed transmission. A transmitting device may modulate a physical layer convergence protocol (PLCP) protocol data unit (PPDU) on a number (M) of tones representing a logical RU associated with the legacy tone plan and may further map the M tones to M noncontiguous subcarrier indices associated with a wireless channel. The transmitting device may transmit the PPDU, over the wireless channel, with a number (N) of pilot tones each having a respective location relative to the M tones as mapped to the M noncontiguous subcarrier indices. In some implementations, the relative locations of the N pilot tones may be different than relative locations of a number (K) of pilot tones associated with the logical RU.Type: ApplicationFiled: July 30, 2021Publication date: February 16, 2023Inventors: Lin YANG, Bin TIAN, Youhan KIM, Qifan CHEN
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Patent number: 10922314Abstract: A technique includes determining a statistic for values associated with at least one column of a database based at least in part on a first sample of the values; and determining a degree of change in a second sample of the values relative to the first sample; and estimating a count of unique values for the column(s). The estimation of the count of unique values includes selectively incrementally updating the statistic using the second sample based at least in part on the determined degree of change; and basing estimation of the count at least in part on the updated statistic. The technique further includes processing a query to the database based at least in part on the count.Type: GrantFiled: April 29, 2015Date of Patent: February 16, 2021Assignee: MICRO FOCUS LLCInventors: QiFan Chen, Choudur Lakshminarayan
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Patent number: 10452676Abstract: A method of managing a database including creating an initial counting bloom filter (CBF) instance having an array of counters and hash functions that map an inserted value to the array of counters, and designating the initial CBF instance as a current CBF instance, and sequentially inserting each value of a sample data set of a table column into the hash functions of the current CBF instance and incrementing counters of the array of counters to which the value is mapped. The method further includes, prior to inserting each value into the hash functions of the current CBF instance, when a number of counters of the array of counters having non-zero values is at least at a threshold level, designating the current CBF instance as an old CBF instance, creating a new CBF instance having an array of counters and hash functions that map an inserted value to the array counters, and designating the new CBF instance as the current CBF instance.Type: GrantFiled: January 31, 2014Date of Patent: October 22, 2019Assignee: Hewlett Packard Enterprise Development LPInventors: QiFan Chen, Ramakumar Kosuru, Choudur Lakshminarayan
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Patent number: 10430411Abstract: Incrementally updating statistics includes sampling rows from a database column in a database to generate a first sample, sampling a subset of modified rows from the database column after generating the first sample to generate a second sample, determining whether distribution changes occurred to the database column based on the first and second samples, and updating a database statistic about the database column in response to determining that a distribution change exists.Type: GrantFiled: April 30, 2013Date of Patent: October 1, 2019Assignee: MICRO FOCUS LLCInventors: Choudur Lakshminarayan, Ramakumar Kosuru, QiFan Chen, Hansjorg Zeller
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Publication number: 20180107715Abstract: A technique includes determining a statistic for values associated with at least one column of a database based at least in part on a first sample of the values; and determining a degree of change in a second sample of the values relative to the first sample; and estimating a count of unique values for the column(s). The estimation of the count of unique values includes selectively incrementally updating the statistic using the second sample based at least in part on the determined degree of change; and basing estimation of the count at least in part on the updated statistic. The technique further includes processing a query to the database based at least in part on the count.Type: ApplicationFiled: April 29, 2015Publication date: April 19, 2018Inventors: QiFan Chen, Choudur Lakshminarayan
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Patent number: 9922080Abstract: In one example in accordance with the present disclosure, a method for determining query plans includes obtaining a current query and generating a first literal and a first signature key from the current query. The method includes determining that the first signature key matches a second signature key stored in a parser cache and obtaining a literals data structure corresponding to the second signature key. The literals data structure comprises a group of literals, a list of high and low boundary intervals and a parameterization indicator. The method includes identifying, using the parameterization indicator, a parameterized literal in the group of literals. The method includes determining that a high and low boundary interval for the second parameterized literal contains the first literal and executing a stored query plan on the current query.Type: GrantFiled: June 11, 2015Date of Patent: March 20, 2018Assignee: Hewlett Packard Enterprise Development LPInventors: Qifan Chen, Hao Qin, Taoufik Ben Abdellatif
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Publication number: 20170024433Abstract: Query plan post optimization analysis and reoptimization can include analyzing query plans input from a query plan optimizer, identifying a suboptimal query plan among the input query plans, and applying corrective actions to reoptimize the identified suboptimal query plan before execution.Type: ApplicationFiled: April 29, 2014Publication date: January 26, 2017Inventors: Ravisha Neelakanthappa, Qifan Chen
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Publication number: 20160364447Abstract: In one example in accordance with the present disclosure, a method for determining query plans includes obtaining a current query and generating a first literal and a first signature key from the current query. The method includes determining that the first signature key matches a second signature key stored in a parser cache and obtaining a literals data structure corresponding to the second signature key. The literals data structure comprises a group of literals, a list of high and low boundary intervals and a parameterization indicator. The method includes identifying, using the parameterization indicator, a parameterized literal in the group of literals. The method includes determining that a high and low boundary interval for the second parameterized literal contains the first literal and executing a stored query plan on the current query.Type: ApplicationFiled: June 11, 2015Publication date: December 15, 2016Inventors: Qifan Chen, Hao Qin, Taoufik Ben Abdellatif
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Publication number: 20160342667Abstract: A method of managing a database including creating an initial counting bloom filter (CBF) instance having an array of counters and hash functions that map an inserted value to the array of counters, and designating the initial CBF instance as a current CBF instance, and sequentially inserting each value of a sample data set of a table column into the hash functions of the current CBF instance and incrementing counters of the array of counters to which the value is mapped. The method further includes, prior to inserting each value into the hash functions of the current CBF instance, when a number of counters of the array of counters having non-zero values is at least at a threshold level, designating the current CBF instance as an old CBF instance, creating a new CBF instance having an array of counters and hash functions that map an inserted value to the array counters, and designating the new CBF instance as the current CBF instance.Type: ApplicationFiled: January 31, 2014Publication date: November 24, 2016Applicant: HEWLETT PACKARD ENTERPRISE DEVELOPMENT LPInventors: QiFan Chen, Ramakumar Kosuru, Choudur Lakshminarayan
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Patent number: 9465826Abstract: A method of estimating a number of unique entry counts of an attribute in a database comprises, with a processor: identifying a sample of entries from an attribute database, determining frequencies of a number of input observations of the sample of entries, determining a number of high frequency values of the sample of entries, and estimating a number of unique entry counts of an attribute within the attribute database using a counting Bloom filter and based on the frequencies of the input observations and the high frequency values.Type: GrantFiled: November 27, 2012Date of Patent: October 11, 2016Assignee: Hewlett Packard Enterprise Development LPInventors: Choudur Lakshminarayan, Hansjorg Zeller, QiFan Chen, Ramakumar Kosuru
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Patent number: 9429642Abstract: A method and apparatus are disclosed for searching for a radar signal within signals received by a wireless device. The wireless device may receive signals within a first frequency segment and a second frequency segment, which is adjacent to the first frequency segment. The wireless device may search for the radar signal within the first frequency segment or the second frequency segment based, at least in part, on Fast Fourier Transform bins associated with the received signals.Type: GrantFiled: August 21, 2015Date of Patent: August 30, 2016Assignee: QUALCOMM IncorporatedInventors: Meriam Khufu Ragheb Rezk, Qifan Chen, Kapil Rai
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Patent number: 9348869Abstract: A method for creating a joined data set from a join input data set is disclosed. The method starts by categorizing the join input data set into a high-skew data set and a low-skew data set. The low-skew data set is distributed to the plurality of CPUs using a first distribution method. The high-skew data set is distributed to the plurality of CPUs using a second distribution method. The plurality of CPUs process the high-skew data set and the low-skew data set to create the joined data set.Type: GrantFiled: January 23, 2012Date of Patent: May 24, 2016Assignee: Hewlett Packard Enterprise Development LPInventors: Awny K. Al-Omari, QiFan Chen, Gregory S. Battas, Kashif A. Siddiqui, Michael J. Hanlon
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Publication number: 20160110417Abstract: Incrementally updating statistics includes sampling rows from a database column in a database to generate a first sample, sampling a subset of modified rows from the database column after generating the first sample to generate a second sample, determining whether distribution changes occurred to the database column based on the first and second samples, and updating a database statistic about the database column in response to determining that a distribution change exists.Type: ApplicationFiled: April 30, 2013Publication date: April 21, 2016Inventors: Choudur Lakshminarayan, Ramakumar Kosuru, QiFan Chen, Hansjorg Zeller
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Patent number: D966009Type: GrantFiled: June 23, 2021Date of Patent: October 11, 2022Inventor: Qifan Chen