Patents by Inventor Aamod Khandekar

Aamod Khandekar 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: 20120140838
    Abstract: Transmission schemes that can flexibly achieve the desired spatial multiplexing order, spatial diversity order, and channel estimation overhead order are described. For data transmission, the assigned subcarriers and spatial multiplexing order (M) for a receiver are determined, where M?1. For each assigned subcarrier, M virtual antennas are selected from among V virtual antennas formed with V columns of an orthonormal matrix, where V?M. V may be selected to achieve the desired spatial diversity order and channel estimation overhead order. Output symbols are mapped to the M virtual antennas selected for each assigned subcarrier by applying the orthonormal matrix. Pilot symbols are also mapped to the V virtual antennas. The mapped symbols are provided for transmission from T transmit antennas, where T?V. Transmission symbols are generated for the mapped symbols, e.g., based on OFDM or SC-FDMA. Different cyclic delays may be applied for the T transmit antennas to improve diversity.
    Type: Application
    Filed: October 11, 2011
    Publication date: June 7, 2012
    Applicant: QUALCOMM Incorporated
    Inventors: Tamer Kadous, Aamod Khandekar, Dhananjay Ashok Gore, Alexei Gorokhov
  • Publication number: 20120140798
    Abstract: Transmission schemes that can flexibly achieve the desired spatial multiplexing order, spatial diversity order, and channel estimation overhead order are described. For data transmission, the assigned subcarriers and spatial multiplexing order (M) for a receiver are determined, where M?1. For each assigned subcarrier, M virtual antennas are selected from among V virtual antennas formed with V columns of an orthonormal matrix, where V?M. V may be selected to achieve the desired spatial diversity order and channel estimation overhead order. Output symbols are mapped to the M virtual antennas selected for each assigned subcarrier by applying the orthonormal matrix. Pilot symbols are also mapped to the V virtual antennas. The mapped symbols are provided for transmission from T transmit antennas, where T?V. Transmission symbols are generated for the mapped symbols, e.g., based on OFDM or SC-FDMA. Different cyclic delays may be applied for the T transmit antennas to improve diversity.
    Type: Application
    Filed: October 11, 2011
    Publication date: June 7, 2012
    Applicant: QUALCOMM Incorporated
    Inventors: Tamer Kadous, Aamod Khandekar, Dhananjay Ashok Gore, Alexei Gorokhov
  • Publication number: 20120120925
    Abstract: Transmission schemes that can flexibly achieve the desired spatial multiplexing order, spatial diversity order, and channel estimation overhead order are described. For data transmission, the assigned subcarriers and spatial multiplexing order (M) for a receiver are determined, where M?1. For each assigned subcarrier, M virtual antennas are selected from among V virtual antennas formed with V columns of an orthonormal matrix, where V?M. V may be selected to achieve the desired spatial diversity order and channel estimation overhead order. Output symbols are mapped to the M virtual antennas selected for each assigned subcarrier by applying the orthonormal matrix. Pilot symbols are also mapped to the V virtual antennas. The mapped symbols are provided for transmission from T transmit antennas, where T?V. Transmission symbols are generated for the mapped symbols, e.g, based on OFDM or SC-FDMA. Different cyclic delays may be applied for the T transmit antennas to improve diversity.
    Type: Application
    Filed: October 11, 2011
    Publication date: May 17, 2012
    Applicant: QUALCOMM Incorporated
    Inventors: Tamer Kadous, Aamod Khandekar, Dhananjay Ashok Gore, Alexei Gorokhov
  • Publication number: 20120120861
    Abstract: Methods and apparatus for assigning, identifying and controlling broadcast transmissions are disclosed. A broadcast flow is assigned to a broadcast logical channel of the physical resources of a wireless communication channel. A broadcast channel control message indicative of parameters of the broadcast logical channel is generated. Upon receipt, the broadcast channel control message is processed and used to accordingly process the received broadcast transmission.
    Type: Application
    Filed: February 9, 2011
    Publication date: May 17, 2012
    Applicant: QUALCOMM Incorporated
    Inventors: Sandip Sarkar, Aamod Khandekar, Tamer Kadous
  • Patent number: 8179876
    Abstract: A method for receiving an indication to apply a first modulation scheme to modulate one or more segments of a first portion includes determining a first segment set, having at least one segment of the first portion for applying the first modulation scheme. The method further includes modulating the first segment set of the first portion using the first modulation scheme. In addition, the method includes modulating one or more segments of the second portion using a second scheme, different from first modulation scheme.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: May 15, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Avneesh Agrawal, Aamod Khandekar, Arak Sutivong, Alexei Gorokhov
  • Patent number: 8159928
    Abstract: Interference management is provided through use of a user-based interference control and/or a network-based interference control. For user-based interference control, the terminals are informed of the inter-sector interference observed by the neighbor sectors and can adjust their transmit powers accordingly so that the inter-sector interference is maintained within acceptable levels. For network-based interference control, each sector is informed of the inter-sector interference observed by the neighbor sectors and regulates data transmissions for its terminals such that the inter-sector interference is maintained within acceptable levels. Each system may utilize only user-based interference control, or only network-based interference control, or both.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: April 17, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Alexei Gorokhov, Aamod Khandekar, Ravi Palanki
  • Publication number: 20120089890
    Abstract: Techniques for encoding and decoding data are described. In an aspect, multiple code rates for a forward error correction (FEC) code may be supported, and a suitable code rate may be selected based on packet size. A transmitter may obtain at least one threshold to use for code rate selection, determine a packet size to use for data transmission, and select a code rate from among the multiple code rates based on the packet size and the at least one threshold. In another aspect, multiple FEC codes of different types (e.g., Turbo, LDPC, and convolutional codes) may be supported, and a suitable FEC code may be selected based on packet size. The transmitter may obtain at least one threshold to use for FEC code selection and may select an FEC code from among the multiple FEC codes based on the packet size and the at least one threshold.
    Type: Application
    Filed: December 20, 2011
    Publication date: April 12, 2012
    Applicant: QUALCOMM Incorporated
    Inventors: Ravi PALANKI, Jeremy H. LIN, Aamod KHANDEKAR, Alexei GOROKHOV, Avneesh AGRAWAL
  • Patent number: 8156389
    Abstract: A pruned bit-reversal interleaver supports different packet sizes and variable code rates and provides good spreading and puncturing properties. To interleave data, a packet of input data of a first size is received. The packet is extended to a second size that is a power of two, e.g., by appending padding or properly generating write addresses. The extended packet is interleaved in accordance with a bit-reversal interleaver of the second size, which reorders the bits in the extended packet based on their indices. A packet of interleaved data is formed by pruning the output of the bit-reversal interleaver e.g., by removing the padding or properly generating read addresses. The pruned bit-reversal interleaver may be used in combination with various types of FEC codes such as a Turbo code, a convolutional code, or a low density parity check (LDPC) code.
    Type: Grant
    Filed: February 14, 2009
    Date of Patent: April 10, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Ravi Palanki, Aamod Khandekar
  • Patent number: 8156390
    Abstract: A pruned bit-reversal interleaver supports different packet sizes and variable code rates and provides good spreading and puncturing properties. To interleave data, a packet of input data of a first size is received. The packet is extended to a second size that is a power of two, e.g., by appending padding or properly generating write addresses. The extended packet is interleaved in accordance with a bit-reversal interleaver of the second size, which reorders the bits in the extended packet based on their indices. A packet of interleaved data is formed by pruning the output of the bit-reversal interleaver, e.g., by removing the padding or properly generating read addresses. The pruned bit-reversal interleaver may be used in combination with various types of FEC codes such as a Turbo code, a convolutional code, or a low density parity check (LDPC) code.
    Type: Grant
    Filed: June 23, 2009
    Date of Patent: April 10, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Ravi Palanki, Aamod Khandekar
  • Publication number: 20120083302
    Abstract: Systems and methods that facilitate management of interference and communication resources are provided. A differential approach is devised in which other-sector interference (OSI) and communication resources are managed by adjusting an offset (delta) value associated with the resources in response to receiving an indication of other-sector interference. An OSI indication can be issued based on a short and a long time scale, and effective interference metrics over time-frequency resources. The adjusted delta value is communicated to a serving access point, which reassigns communication resources in order to mitigate other-sector interference.
    Type: Application
    Filed: December 14, 2011
    Publication date: April 5, 2012
    Applicant: QUALCOMM INCORPORATED
    Inventors: Mohammad Jaber Borran, Alexei Gorokhov, Aamod Khandekar, Tingfang Ji, Arumugam Chendamarai Kannan
  • Publication number: 20120063293
    Abstract: A method includes scrambling a Walsh sequence with a random sequence to produce a scrambled Walsh sequence. The method also includes transmitting the scrambled Walsh sequence as an access-based handoff probe.
    Type: Application
    Filed: August 17, 2011
    Publication date: March 15, 2012
    Applicant: QUALCOMM Incorporated
    Inventors: Aamod Khandekar, Alexei Gorokhov, Naga Bhushan
  • Patent number: 8135088
    Abstract: A transmitter generates a pilot having a constant time-domain envelope and a flat frequency spectrum based on a polyphase sequence. To generate a pilot IFDMA symbol, a first sequence of pilot symbols is formed based on the polyphase sequence and replicated multiple times to obtain a second sequence of pilot symbols. A phase ramp is applied to the second pilot symbol sequence to obtain a third sequence of output symbols. A cyclic prefix is appended to the third sequence of output symbols to obtain an IFDMA symbol, which is transmitted in the time domain via a communication channel. The pilot symbols may be multiplexed with data symbols using TDM and/or CDM. A pilot LFDMA symbol may also be generated with a polyphase sequence and multiplexed using TDM or CDM. A receiver derives a channel estimate based on received pilot symbols and using minimum mean-square error, least-squares, or some other channel estimation technique.
    Type: Grant
    Filed: July 5, 2005
    Date of Patent: March 13, 2012
    Assignee: Q1UALCOMM Incorporated
    Inventors: Ravi Palanki, Aamod Khandekar
  • Patent number: 8135026
    Abstract: Techniques for supporting communication with disjoint links and common links are described. A sector may broadcast an overhead message and/or send unicast messages to indicate whether the sector supports disjoint links. A terminal may receive at least one message indicating whether disjoint links are supported by at least one sector. When disjoint links are supported, a forward link (FL) serving sector and a reverse link (RL) serving sector may be independently selected for the terminal. When disjoint links are not supported, a single sector may be selected as both the FL and RL serving sectors for the terminal. Handoff of the terminal may be performed independently for the forward and reverse links if disjoint links are supported and may be performed jointly if disjoint links are not supported.
    Type: Grant
    Filed: January 4, 2007
    Date of Patent: March 13, 2012
    Assignee: QUALCOMM, Incorporated
    Inventor: Aamod Khandekar
  • Patent number: 8098710
    Abstract: Techniques for efficiently designing random hopping patterns in a communications system are disclosed. The disclosed embodiments provide for methods and systems for generating random hopping patterns, updating the patterns frequently, generating different patterns for different cells/sectors, and generating patterns of nearby sub-carriers for block hopping.
    Type: Grant
    Filed: November 16, 2010
    Date of Patent: January 17, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Ravi Palanki, Aamod Khandekar
  • Patent number: 8098711
    Abstract: Techniques for efficiently designing random hopping patterns in a communications system are disclosed. The disclosed embodiments provide for methods and systems for generating random hopping patterns, updating the patterns frequently, generating different patterns for different cells/sectors, and generating patterns of nearby sub-carriers for block hopping.
    Type: Grant
    Filed: November 16, 2010
    Date of Patent: January 17, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Ravi Palanki, Aamod Khandekar
  • Publication number: 20120002623
    Abstract: To support mobile stations that are not capable of demodulating the entire bandwidth or that can be made to demodulate less than the entire bandwidth, a system, apparatus and method are provided to schedule users on less than all of the bandwidth. Further, certain users can be scheduled on more of the bandwidth than others.
    Type: Application
    Filed: July 7, 2011
    Publication date: January 5, 2012
    Applicant: QUALCOMM Incorporated
    Inventors: Aamod Khandekar, Alexei Gorokhov, Avneesh Agrawal, Rajiv Vijayan, Edward Harrison Teague, Fatih Ulupinar
  • Patent number: 8085875
    Abstract: Dynamic resource allocation systems, apparatus, and methods are disclosed for selectively improving the ability of a receiver to determine a channel estimate in an Orthogonal Frequency Division Multiple Access (OFDMA) system. A wireless communication system can use a common pilot channel configuration to aid channel estimation in one or more receivers in communication with the system. A receiver in communication with the system may be unable to demodulate received data due to an inaccurate channel estimate. The receiver can communicate to a transmitter in the system a request for additional channel estimation resources. The wireless communication system can provide additional channel estimation resources by inserting dedicated pilot channels into one or more of the frequencies allocated to symbols for the receiver. If the receiver is still unable to demodulate received data, the wireless communication system can incrementally insert additional pilot channels in the symbol associated with the receiver.
    Type: Grant
    Filed: May 13, 2005
    Date of Patent: December 27, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Dhananjay Ashok Gore, Avneesh Agrawal, Aamod Khandekar
  • Patent number: 8078135
    Abstract: A method and apparatus for transmitting and processing a QuickChannelInfo block is described. A plurality of superframe indices are determined, and a QuickChannelInfo block is transmitted to an access terminal in the superframe with an odd superframe index. The contents of the QuickChannelInfo block are changed in accordance with a QuickChannelInfo Validity field of the QuickChannelInfo block. It is determined if a multi-carrier mode of a protocol is MultiCarrierOn. The QuickChannelInfo block is transmitted on each carrier of the protocol. The QuickChannelInfo block is transmitted to the access terminal over a communication link. The QuickChannelInfo block is processed after the QuickChannelInfo block is received at the access terminal over the communication link.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: December 13, 2011
    Assignee: Qualcomm Incorporated
    Inventors: Rajat Prakash, Fatih Ulupinar, Edward Harrison Teague, Arak Sutivong, Aamod Khandekar, Alexei Gorokhov
  • Patent number: 8077692
    Abstract: Enhanced frequency division multiple access (EFDMA) is a multiplexing scheme that sends modulation symbols in the time domain and achieves a lower PAPR than OFDM. An EFDMA symbol occupies multiple subband groups that are spaced apart in a frequency band, with each subband group containing multiple adjacent subbands. To generate an EFDMA symbol, multiple modulation symbols are mapped onto a first sequence of symbols. A transform (e.g., a DFT) is performed on the first sequence to obtain a second sequence of values. The values in the second sequence corresponding to the subbands used for the EFDMA symbol are retained, and the remaining values are zeroed out to obtain a third sequence of values. An inverse transform (e.g., an IDFT) is performed on the third sequence to obtain a fourth sequence of samples. A phase ramp may be applied on the fourth sequence, and a cyclic prefix is appended to form the EFDMA symbol.
    Type: Grant
    Filed: May 10, 2006
    Date of Patent: December 13, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Aamod Khandekar, Ravi Palanki
  • Patent number: 8068530
    Abstract: Each base station transmits a TDM pilot 1 having multiple instances of a pilot-1 sequence generated with a PN1 sequence and a TDM pilot 2 having at least one instance of a pilot-2 sequence generated with a PN2 sequence. Each base station is assigned a specific PN2 sequence that uniquely identifies that base station. A terminal uses TDM pilot 1 to detect for the presence of a signal and uses TDM pilot 2 to identify base stations and obtain accurate timing. For signal detection, the terminal performs delayed correlation on received samples and determines whether a signal is present. If a signal is detected, the terminal performs direct correlation on the received samples with PN1 sequences for K1 different time offsets and identifies K2 strongest TDM pilot 1 instances. For time synchronization, the terminal performs direct correlation on the received samples with PN2 sequences to detect for TDM pilot 2.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: November 29, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Aamod Khandekar, Avneesh Agrawal