Patents by Inventor Subburajan Ponnuswamy

Subburajan Ponnuswamy 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).

  • Publication number: 20160064808
    Abstract: According to one embodiment of the invention, a network device comprises a plurality of antennas comprising a first antenna, wherein the first antenna comprises: a first set of one or more elements that form an Alford loop and that is configured for electrical excitation via a current transmitted over a conductive medium from a signal source and a second set of one or more elements that is configured for electromagnetic induction without contact with the conductive medium from the signal source.
    Type: Application
    Filed: August 28, 2014
    Publication date: March 3, 2016
    Inventors: Ahmed Khidre, James W. Jervis, Subburajan Ponnuswamy
  • Publication number: 20160033613
    Abstract: Disclosed herein, one embodiment of the disclosure is directed to a system, apparatus, and method for location estimation in the presence of multipath/non-line-of-sight (NLOS) conditions. Various methods have been contemplated to detect the level of multipath/NLOS propagation between two devices. A SNR variation method determines how the SNR of each chain/stream is varying over a time window in order to detect the chain/stream with least local scattering or multipath. A measure of coherence SNR is defined to measure the level of multipath/N LOS per-chain/stream. Moreover, since per-subcarrier SNR information is available at the one or both nodes, the coherence methods can be used on a per-subcarrier basis to detect multipath/NLOS for the entire channel, for the specific spatial stream or for the specific frequencies occupied by the subcarriers. Furthermore, a coherence bandwidth estimation method uses the SNR variation over subcarriers to detect the coherence bandwidth of the spatial stream.
    Type: Application
    Filed: July 30, 2014
    Publication date: February 4, 2016
    Inventors: Dongwoon Hahn, Subburajan Ponnuswamy
  • Publication number: 20160033617
    Abstract: Disclosed herein, one embodiment of the disclosure is directed to a system, apparatus, and method for location estimation in the presence of multipath/non-line-of-sight (NLOS) conditions. Various methods have been contemplated to detect the level of multipath/NLOS propagation between two devices. A SNR variation method determines how the SNR of each chain/stream is varying over a time window in order to detect the chain/stream with least local scattering or multipath. A measure of coherence SNR is defined to measure the level of multipath/N LOS per-chain/stream. Moreover, since per-subcarrier SNR information is available at the one or both nodes, the coherence methods can be used on a per-subcarrier basis to detect multipath/NLOS for the entire channel, for the specific spatial stream or for the specific frequencies occupied by the subcarriers. Furthermore, a coherence bandwidth estimation method uses the SNR variation over subcarriers to detect the coherence bandwidth of the spatial stream.
    Type: Application
    Filed: July 30, 2014
    Publication date: February 4, 2016
    Inventors: Dongwoon Hahn, Subburajan Ponnuswamy
  • Publication number: 20160037458
    Abstract: The present disclosure discloses a method and system for adaptive cell size management. The system can determine a minimum SNR value and one or more current environmental factors for a particular environment. Also, the system dynamically determines a minimum signal strength value for receiving wireless signals based on the minimum SNR value and the one or more current environmental factors, and configures a network device to receive signals with the minimum signal strength value. Alternatively, the system can estimate a particular coverage area such that a first set of wireless signals transmitted by devices located within the particular coverage area reach a network device at a minimum signal strength. The system then computes a transmission power such that a second set of wireless signals transmitted by the network device at the transmission power reaches an edge of the particular coverage area at a particular signal strength value.
    Type: Application
    Filed: July 29, 2014
    Publication date: February 4, 2016
    Applicant: Aruba Networks, Inc.
    Inventors: Subburajan Ponnuswamy, Neal Castagnoli
  • Publication number: 20160037330
    Abstract: Disclosed herein, one embodiment of the disclosure is directed to a system, apparatus, and method for grouping client devices for simultaneous MU-MIMO transmissions. When client devices are being grouped for simultaneous MU-MIMO transmissions, a first wireless network device may obtain information corresponding to a plurality of client devices that are associated with the first wireless network device. This information may correspond to signals received from one or more of the client devices by each of the wireless network devices other than the first wireless network device. Then, a subset of the client devices may be selected for concurrent communications based, at least in part, on the information corresponding to the plurality of client devices for concurrent communication. Thereafter, the subset of client devices, referred to as the first group, may be concurrently communicated with.
    Type: Application
    Filed: July 29, 2014
    Publication date: February 4, 2016
    Inventor: Subburajan Ponnuswamy
  • Patent number: 9179495
    Abstract: A technique is disclosed to schedule frame transmissions in a wireless network utilizing scheduled TDMA by synchronizing clocks in repeater and backhaul access points.
    Type: Grant
    Filed: July 8, 2003
    Date of Patent: November 3, 2015
    Assignee: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.
    Inventors: Shimon B. Scherzer, Patrick A. Worfolk, Armin D. Haken, Subburajan Ponnuswamy, Ronen Vainish
  • Publication number: 20150304011
    Abstract: Disclosed herein is a system, apparatus, and method for using an antenna system comprising individually configurable antenna circuitries in a wireless network device to simulate the standard MU-MIMO transmissions as specified in the IEEE 802.11ac standard with antenna beamforming. The individually configurable antenna circuitries can be configured to transmit radio frequency (RF) signals with specific radiation patterns including directional beam patterns. Client devices may be grouped and antenna circuitries may be configured in such a way as to minimize inter-user interference. Frequent sounding-channel state feedback cycles and associated overhead are obviated with antenna beamforming, and no change to standard-compliant client devices is necessary. A better overall performance compared to MU-MIMO based on DSP-based beamforming as specified in the IEEE 802.11ac standard is expected.
    Type: Application
    Filed: April 18, 2014
    Publication date: October 22, 2015
    Applicant: ARUBA NETWORKS, INC.
    Inventor: Subburajan Ponnuswamy
  • Patent number: 9167457
    Abstract: Methods of calculating and displaying quality metrics on a wireless digital network such as a network using IEEE 802.11 Wi-Fi standards. The quality metric calculation assigns weights only to factors which are observed above a threshold, combining multiple factors into a scalar result. The quality metric is derived from the weighted sum of two or more parameters such as: noise floor offset, channel busy indication, adjacent and overlapping channel interference, interferer duty-cycle, frame retry-rate, PHY error rate and CRC error rate. Quality spectrograms may be used to display calculated quality metrics across a channel, channel range, or frequency band, plotting calculated quality metric versus frequency or channel range over a configurable time frame. Using known locations of radios, quality ranges are mapped onto visual representations such as contour lines, shading density, or color codes, and overlayed for example over floor plans or other site representations.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: October 20, 2015
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Subburajan Ponnuswamy
  • Patent number: 9130871
    Abstract: Interference classification with minimal or incomplete information. Receivers in access points and in other network devices on a wireless digital network may be switched to a spectrum monitor mode in which they provide amplitude-versus-frequency information for a chosen part of the spectrum. This may be performed by performing a FFT or similar transform on the signals from the receiver. Receivers are calibrated with known interference sources in controlled environments to determine peaks, pulse frequency, bandwidth, and other identifying parameters of the interference source in best and worst case conditions. These calibrated values are used for matching interference signatures. Calibration is also performed using partial signatures collected over a short period in the order of microseconds. These partial signals may be used to detect interferers while scanning.
    Type: Grant
    Filed: February 20, 2014
    Date of Patent: September 8, 2015
    Assignee: ARUBA NETWORKS, INC.
    Inventor: Subburajan Ponnuswamy
  • Patent number: 9113335
    Abstract: Distributed load balancing in wireless digital networks. In a network having a plurality of access nodes with at least one wireless client connected to a first access node, the client is encouraged to move to a different access node by reducing the apparent signal strength of transmissions from the access node to the client. Apparent signal strength can be reduced by reducing transmit power, by using beam forming, antenna switching, or a combination. Other access nodes may send unsolicited frames, such as probe response frames to the client, encouraging the client to move.
    Type: Grant
    Filed: April 30, 2008
    Date of Patent: August 18, 2015
    Assignee: Aruba Networks Inc.
    Inventor: Subburajan Ponnuswamy
  • Publication number: 20150230110
    Abstract: A combination and correlation of data from multiple sensors in a wireless digital network is described. Sensors such as spectrum monitors, access points, and wireless client devices provide spectrum data to one or more central stations connected to the network. Spectrum data from multiple sensors is combined and correlated to provide insight into network operation such as spectrum maps, detection-range maps, and for network diagnostics. Sensors providing spectrum data may be synchronized. Correlating spectrum data from synchronized sensors allows more accurate location of sources such as interferers. The known EIRP of certain wireless devices may be used to improve location estimates, and these devices may be used as calibrations sources for sensors in the wireless network.
    Type: Application
    Filed: April 20, 2015
    Publication date: August 13, 2015
    Inventor: Subburajan Ponnuswamy
  • Patent number: 9107219
    Abstract: A method includes detecting a first value for a first parameter associated with a first access point of a plurality of access points and based at least on the first value for the first parameter associated with the first access point, configuring a second value for a second parameter associated with a second access point of the plurality of access points.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: August 11, 2015
    Assignee: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.
    Inventors: Pradeep Iyer, Subburajan Ponnuswamy
  • Publication number: 20150215025
    Abstract: Disclosed herein is a system, apparatus, and method for adaptive per-user multipath control for spatial multiplexing gain in MIMO systems. Transmission parameters relating to Cyclic Shifts and/or Radio Frequency (RF) antenna beams are modified and tested to find optimal transmission parameters that enable better exploitation of multipath RF propagation and therefore better spatial multiplexing gain.
    Type: Application
    Filed: January 30, 2014
    Publication date: July 30, 2015
    Applicant: ARUBA NETWORKS, INC.
    Inventor: Subburajan Ponnuswamy
  • Publication number: 20150188620
    Abstract: According to one embodiment of the disclosure, a non-transitory computer-readable medium comprising instructions which, when executed by one or more hardware processors, causes performance of operations. One of these operations comprises transmitting, from a first device to a second device, a first plurality of frames using a first polarization configuration for a first antenna corresponding to the first device. Based on feedback information associated with the first plurality of frames, a second polarization configuration, which is different than the first polarization configuration, is selected for transmitting a second plurality of frames. Thereafter, the second plurality of frames is transmitted from the first device to the second device using the second polarization configuration for the first antenna.
    Type: Application
    Filed: December 26, 2013
    Publication date: July 2, 2015
    Applicant: ARUBA NETWORKS, INC.
    Inventor: Subburajan Ponnuswamy
  • Patent number: 9041604
    Abstract: Multi-pattern transmission of frames. The method of operations comprises transmitting a first portion of a frame using a first radiation pattern. The frame comprises one or more preambles and a single data portion associated with the one or more preambles. Thereafter, an operation is conducted to switch the radiation pattern from the first radiation pattern, used to produce the first portion of the frame, to a second radiation pattern. A second portion of the same frame is produced using the second radiation pattern.
    Type: Grant
    Filed: July 10, 2012
    Date of Patent: May 26, 2015
    Assignee: ARUBA NETWORKS, INC.
    Inventor: Subburajan Ponnuswamy
  • Publication number: 20150133063
    Abstract: A method includes computing a minimum sensitivity threshold value for a particular wireless device, configuring the particular wireless device to receive wireless signals with a signal strength higher than the minimum sensitivity threshold value, distributing the minimum sensitivity threshold value to other wireless devices, and configuring the other wireless devices based on the minimum sensitivity threshold value for the particular wireless device.
    Type: Application
    Filed: November 10, 2014
    Publication date: May 14, 2015
    Applicant: ARUBA NETWORKS, INC.
    Inventor: Subburajan Ponnuswamy
  • Publication number: 20150131467
    Abstract: Methods of operating devices on a wireless network as access points (AP) or spectrum monitors (SM). An adaptive radio management (ARM) process operating on the digital network senses network conditions based on data from APs and SMs on the network, and in response to conditions changes devices from AP operation to SM operation, and from SM operation back to AP operation. A method for providing wideband spectrum analysis functions on a radio operating as an AP on a channel proving client connectivity services. A method for scanning off-channel for shorter durations between transmissions to collect spectral data and a method for explicitly quieting IEEE 802.11 transmissions on a channel to collect spectral data.
    Type: Application
    Filed: November 10, 2014
    Publication date: May 14, 2015
    Applicant: ARUBA NETWORKS, INC.
    Inventor: Subburajan Ponnuswamy
  • Publication number: 20150117324
    Abstract: Disclosed is a system, apparatus, and method for RF management using network-device-to-network-device channel estimation and standard beamforming techniques. The exemplary method comprises: obtaining a first information corresponding to a first device that is a target device for transmitting at least one of a plurality of wireless signals by a network device; obtaining a second information corresponding to a second device that is to be avoided by propagation of any wireless signals transmitted by the network device; computing a radiation pattern for transmitting the plurality of wireless signals based at least on the first information associated with the first device and the second information associated with the second device; and transmitting the plurality of wireless signals based on the radiation pattern.
    Type: Application
    Filed: October 31, 2013
    Publication date: April 30, 2015
    Applicant: Aruba Networks, Inc.
    Inventor: Subburajan PONNUSWAMY
  • Publication number: 20150117325
    Abstract: Disclosed herein is a system, apparatus, and method for optimizing sounding and feedback overhead in a wireless digital network utilizing a beamforming technique by adaptively changing the frequency of sounding transmissions.
    Type: Application
    Filed: October 31, 2013
    Publication date: April 30, 2015
    Applicant: Aruba Networks, Inc.
    Inventor: Subburajan PONNUSWAMY
  • Patent number: 9014021
    Abstract: A combination and correlation of data from multiple sensors in a wireless digital network is described. Sensors such as spectrum monitors, access points, and wireless client devices provide spectrum data to one or more central stations connected to the network. Spectrum data from multiple sensors is combined and correlated to provide insight into network operation such as spectrum maps, detection-range maps, and for network diagnostics. Sensors providing spectrum data may be synchronized. Correlating spectrum data from synchronized sensors allows more accurate location of sources such as interferers. The known EIRP of certain wireless devices may be used to improve location estimates, and these devices may be used as calibrations sources for sensors in the wireless network.
    Type: Grant
    Filed: July 8, 2011
    Date of Patent: April 21, 2015
    Assignee: Aruba Networks, Inc.
    Inventor: Subburajan Ponnuswamy