Patents by Inventor Rajaram Ramesh

Rajaram Ramesh 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).

  • Patent number: 8779226
    Abstract: The present invention provides a process for preparing ethylene and/or propylene, comprising the steps of: a) providing an oxygenate-comprising feedstock; b) contacting the oxygenate-comprising feedstock with a molecular sieve-comprising catalyst at a temperature in the range of from 450 to 700° C. and converting at least part of the oxygenate into an olefinic product comprising ethylene and/or propylene; and c) retrieving the olefinic product, wherein the oxygenate-comprising feedstock comprises in the range of from 1 to 97 wt % of at least one tert-alkyl ether selected from the group MTBE, ETBE, TAME and TAEE, based on the weight of the oxygenates in the oxygenate-comprising feedstock, and further comprises methanol and/or DME.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: July 15, 2014
    Assignee: Shell Oil Company
    Inventors: Leslie Andrew Chewter, Rajaram Ramesh, Jeroen Van Westrenen
  • Publication number: 20140173371
    Abstract: A wireless telecommunications network supplies a semi-persistent resource that a wireless station can use for special purposes (such as a retransmission of packets for ARQ purposes or a control signal. The semi-persistent resource can be allocated by the system to other terminals if, e.g., a retransmission is not required. Since a retransmission is generally performed in response to a NACK received from a base station, the NACK may itself serve as a token that permits the wireless station to use the semi-persistent allocation. Thus, the technology includes, e.g., a method for resource allocation on a semi-persistent basis and efficient signaling for the usage of such allocation.
    Type: Application
    Filed: February 7, 2014
    Publication date: June 19, 2014
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Kumar BALACHANDRAN, Havish KOORAPATY, Rajaram Ramesh
  • Patent number: 8754280
    Abstract: The present invention provides a method for start-up of an Oxygenate-to-Olefins process, which process comprises the steps: a) providing an oxygenate-comprising feedstock to an Oxygenate-to-Olefins reaction zone and contacting the feedstock with a zeolite-comprising catalyst at a temperature in the range of from 450 to 700° C. ° C., to obtain an reaction product containing olefins; b) separating the reaction product obtained in step a) in at least a product fraction containing ethylene and/or propylene and a product fraction containing C4+ olefins; c) recycling at least part of the C4+ olefins in the product fraction containing C4+ olefins to the Oxygenate-to-Olefins reaction zone in step (a), characterized in that upon start-up the oxygenate-comprising feedstock initially comprises a first amount of externally supplied tert-alkyl ether and subsequently the amount of externally supplied tert-alkyl ether in the oxygenate-comprising feedstock is reduced.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: June 17, 2014
    Assignee: Shell Oil Company
    Inventors: Leslie Andrew Chewter, Rajaram Ramesh, Sivakumar Sadasivan Vijayakumari, Jeroen Van Westrenen
  • Patent number: 8742188
    Abstract: The present invention provides a process for preparing ethylene and/or propylene and an iso-olefin-depleted olefinic product, comprising the steps of: a) providing a C5 hydrocarbon-comprising stream, comprising C5 cyclopentene and C5 iso-olefins; b) subjecting the C5 hydrocarbon-comprising stream to an etherification process with methanol and/or ethanol wherein at least part of the C5 iso-olefins are converted with methanol and/or ethanol to an tert-alkyl ether, and retrieving an etherification product stream; c) separating at least part of the etherification product stream into at least an ether-enriched stream and a first iso-olefin-depleted olefinic product; d) converting at least part of the tert-alkyl ether in the ether-enriched stream to ethylene and/or propylene by contacting at least part of the ether-enriched stream with a molecular sieve-comprising catalyst at a temperature in the range of from 350 to 1000° C. and retrieving a second olefinic product comprising ethylene and/or propylene.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: June 3, 2014
    Assignee: Shell Oil Company
    Inventors: Leslie Andrew Chewter, Rajaram Ramesh, Sivakumar Sadasivan Vijayakumari, Jeroen Van Westrenen
  • Patent number: 8704027
    Abstract: The present invention provides a process for preparing ethylene and/or propylene, comprising the steps of contacting a stream comprising C4+ olefins with a zeolite-comprising catalyst to retrieve an olefinic product stream comprising ethylene and/or propylene, and a C4+ hydrocarbon fraction, comprising paraffins, normal olefins and iso-olefins. The C4+ hydrocarbon fraction is subjected to an etherification process with wherein at least part of the iso-olefins are converted with methanol and/or ethanol to an tert-alkyl ether and an etherification product stream is retrieved and separated into an ether-enriched stream and an iso-olefin-depleted C4+ hydrocarbon stream. Part of the iso-olefin-depleted C4+ hydrocarbon stream from the process to purge part of the paraffinic C4+ hydrocarbons while another part of the iso-olefin-depleted C4+ hydrocarbon stream is recycled.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: April 22, 2014
    Assignee: Shell Oil Company
    Inventors: Leslie Andrew Chewter, Rajaram Ramesh, Jeroen Van Westrenen
  • Publication number: 20130311858
    Abstract: The iterative decoding of blocks may be continued or terminated based on CRC checks. In an example embodiment, one iteration of an iterative decoding process is performed on a block whose information bits are covered by a CRC. The iterative decoding process is stopped if the CRC checks for a predetermined number of consecutive iterations. In another example embodiment, a decoding iteration is performed on a particular sub-block of multiple sub-blocks of a transport block, which includes a single CRC over an entirety of the transport block. The CRC is checked using decoded bits obtained from the decoding iteration on the particular sub-block and decoded bits obtained from previous decoding iterations on other sub-blocks of the multiple sub-blocks. The decoding iteration is then performed on a different sub-block if the CRC does not check. Also, the decoding iterations for the sub-blocks may be terminated if the CRC checks.
    Type: Application
    Filed: July 31, 2013
    Publication date: November 21, 2013
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Rajaram Ramesh, Havish Koorapaty, Jung-Fu Cheng, Kumar Balachandran
  • Publication number: 20130245292
    Abstract: The present invention provides a process for preparing ethylene and/or propylene and an iso-olefin-depleted olefinic product, comprising the steps of: a) providing a C5 hydrocarbon-comprising stream, comprising C5 cyclopentene and C5 iso-olefins; b) subjecting the C5 hydrocarbon-comprising stream to an etherification process with methanol and/or ethanol wherein at least part of the C5 iso-olefins are converted with methanol and/or ethanol to an tert-alkyl ether, and retrieving an etherification product stream; c) separating at least part of the etherification product stream into at least an ether-enriched stream and a first iso-olefin-depleted olefinic product; d) converting at least part of the tert-alkyl ether in the ether-enriched stream to ethylene and/or propylene by contacting at least part of the ether-enriched stream with a molecular sieve-comprising catalyst at a temperature in the range of from 350 to 1000° C. and retrieving a second olefinic product comprising ethylene and/or propylene.
    Type: Application
    Filed: September 7, 2012
    Publication date: September 19, 2013
    Applicant: SHELL OIL COMPANY
    Inventors: Leslie Andrew CHEWTER, Rajaram RAMESH, Sivakumar SADASIVAN VIJAYAKUMARI, Jeroen VAN WESTRENEN
  • Publication number: 20130245294
    Abstract: The present invention provides a method for start-up of an Oxygenate-to-Olefins process, which process comprises the steps: a) providing an oxygenate-comprising feedstock to an Oxygenate-to-Olefins reaction zone and contacting the feedstock with a zeolite-comprising catalyst at a temperature in the range of from 450 to 700° C. ° C., to obtain an reaction product containing olefins; b) separating the reaction product obtained in step a) in at least a product fraction containing ethylene and/or propylene and a product fraction containing C4+ olefins; c) recycling at least part of the C4+ olefins in the product fraction containing C4+ olefins to the Oxygenate-to-Olefins reaction zone in step (a), characterised in that upon start-up the oxygenate-comprising feedstock initially comprises a first amount of externally supplied tert-alkyl ether and subsequently the amount of externally supplied tert-alkyl ether in the oxygenate-comprising feedstock is reduced.
    Type: Application
    Filed: September 7, 2012
    Publication date: September 19, 2013
    Applicant: SHELL OIL COMPANY
    Inventors: Leslie Andrew CHEWTER, Rajaram RAMESH, Sivakumar SADASIVAN VIJAYAKUMARI, Jeroen VAN WESTRENEN
  • Patent number: 8538464
    Abstract: Code words are assigned to subscriber stations or groups of subscriber stations in a communication network for a quick paging mechanism in which the assigned code words are transmitted as quick paging signals over unused frequency resources to signal the subscriber stations. Subsets of multiple code words from a set of code words can be assigned to respective paging groups, and overlapping subsets can be assigned to multiple paging groups. This enables a single code word to be used to address either a single paging group or multiple paging groups.
    Type: Grant
    Filed: December 30, 2008
    Date of Patent: September 17, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Rajaram Ramesh, Havish Koorapaty, Kumar Balachandran
  • Publication number: 20130237713
    Abstract: The present invention provides a process for preparing ethylene and/or propylene, comprising the steps of contacting a stream comprising C4+ olefins with a zeolite-comprising catalyst to retrieve an olefinic product stream comprising ethylene and/or propylene, and a C4+ hydrocarbon fraction, comprising paraffins, normal olefins and iso-olefins. The C4+ hydrocarbon fraction is subjected to an etherification process with wherein at least part of the iso-olefins are converted with methanol and/or ethanol to an tert-alkyl ether and an etherification product stream is retrieved and separated into an ether-enriched stream and an iso-olefin-depleted C4+ hydrocarbon stream. Part of the iso-olefin-depleted C4+ hydrocarbon stream from the process to purge part of the paraffinic C4+ hydrocarbons while another part of the iso-olefin-depleted C4+ hydrocarbon stream is recycled.
    Type: Application
    Filed: September 7, 2012
    Publication date: September 12, 2013
    Applicant: SHELL OIL COMPANY
    Inventors: Leslie Andrew CHEWTER, Rajaram RAMESH, Jeroen VAN WESTRENEN
  • Publication number: 20130237715
    Abstract: The present invention provides a process for preparing ethylene and/or propylene, comprising the steps of: a) providing an oxygenate-comprising feedstock; b) contacting the oxygenate-comprising feedstock with a molecular sieve-comprising catalyst at a temperature in the range of from 450 to 700° C. and converting at least part of the oxygenate into an olefinic product comprising ethylene and/or propylene; and c) retrieving the olefinic product, wherein the oxygenate-comprising feedstock comprises in the range of from 1 to 97 wt % of at least one tert-alkyl ether selected from the group MTBE, ETBE, TAME and TAEE, based on the weight of the oxygenates in the oxygenate-comprising feedstock, and further comprises methanol and/or DME.
    Type: Application
    Filed: September 7, 2012
    Publication date: September 12, 2013
    Applicant: SHELL OIL COMPANY
    Inventors: Leslie Andrew CHEWTER, Rajaram RAMESH, Jeroen VAN WESTRENEN
  • Patent number: 8526305
    Abstract: The present invention provides systems and methods that enable a base station to consume less power. According to an embodiment of the invention, the base station reduces its power consumption by not continuously broadcasting control information. In such an embodiment, a mobile station that seeks access to a network to which the base station provides access does not search for broadcast control information prior to transmitting an access message to the base station, but rather simply transmits on a predetermined access channel an access request message. A base station that receives the access request message may unicast control information to the mobile station.
    Type: Grant
    Filed: August 26, 2009
    Date of Patent: September 3, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Rajaram Ramesh, Kumar Balachandran, Havish Koorapaty, Stephen Grant
  • Patent number: 8527843
    Abstract: The iterative decoding of blocks may be continued or terminated based on CRC checks. In an example embodiment, one iteration of an iterative decoding process is performed on a block whose information bits are covered by a CRC. The iterative decoding process is stopped if the CRC checks for a predetermined number of consecutive iterations. In another example embodiment, a decoding iteration is performed on a particular sub-block of multiple sub-blocks of a transport block, which includes a single CRC over an entirety of the transport block. The CRC is checked using decoded bits obtained from the decoding iteration on the particular sub-block and decoded bits obtained from previous decoding iterations on other sub-blocks of the multiple sub-blocks. The decoding iteration is then performed on a different sub-block if the CRC does not check. Also, the decoding iterations for the sub-blocks may be terminated if the CRC checks.
    Type: Grant
    Filed: October 25, 2011
    Date of Patent: September 3, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Rajaram Ramesh, Jung-Fu Thomas Cheng, Havish Koorapaty, Kumar Balachandran
  • Patent number: 8447321
    Abstract: A system and method for finding a wireless local area network, WLAN, when a mobile terminal is connected to a cellular network. A position associated with each WLAN operating within the coverage area of the cellular network is stored in a database. At predefined intervals or conditions, the system determines a current position of the mobile terminal, and determines whether the current position of the mobile terminal is close enough to a stored WLAN position for the mobile terminal to connect to the WLAN corresponding to the stored WLAN position. If so, a notification is sent to the mobile terminal indicating that the mobile terminal is within range of the identified WLAN. The mobile terminal then scans for the identified WLAN.
    Type: Grant
    Filed: September 16, 2008
    Date of Patent: May 21, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Kumar Balachandran, Havish Koorapaty, Rajaram Ramesh
  • Publication number: 20130066032
    Abstract: The present invention provides a process for preparing ethylene and/or propylene, comprising providing a hydrocarbon stream, comprising C4+ normal and C4+ iso-olefins; subjecting the hydrocarbon stream to an etherification process wherein the iso-olefins are converted with alcohol to an tert-alkyl ether, and retrieving a first etherification product stream; separating the first etherification product stream into a first ether-enriched stream and an iso-olefin-depleted hydrocarbon stream; converting the normal olefins in the iso-olefin-depleted hydrocarbon stream to ethylene and/or propylene with a molecular sieve-comprising catalyst and retrieving an olefinic product; decomposing the tert-alkyl ether in the ether-enriched stream into alcohol and an iso-olefin; isomerising the obtained iso-olefins to normal-olefins and retrieving an normal-olefin-enriched hydrocarbon stream; and converting the normal olefins in the normal-olefin-enriched hydrocarbon stream to ethylene and/or propylene by contacting the normal-
    Type: Application
    Filed: September 7, 2012
    Publication date: March 14, 2013
    Applicant: SHELL OIL COMPANY
    Inventors: Leslie Andrew CHEWTER, Rajaram RAMESH, Sivakumar SADASIVAN VIJAYAKUMARI, Jeroen VAN WESTRENEN
  • Patent number: 8331272
    Abstract: According to embodiments of the present invention, multiple frames or sub-frames on an uplink channel may be aggregated into one logical unit for demodulation and decoding to allow one data packet to span over multiple frames. Multi-frame aggregation is enabled by modifying the uplink resource allocation messages transmitted to the user terminals. The multi-frame resource allocation message includes a BEGIN FLAG field indicating whether a corresponding frame is the first frame in a multi-frame allocation and a REMAINING RESOURCES field to indicate the number of units (e.g., slots or frames) remaining in the multi-frame allocation.
    Type: Grant
    Filed: April 27, 2009
    Date of Patent: December 11, 2012
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Rajaram Ramesh, Havish Koorapaty, Kumar Balachandran
  • Patent number: 8259827
    Abstract: Methods and apparatus by which receiving stations or other communication network nodes can receive quick paging code words assigned by transmitting stations to the receiving stations. A receiving station can estimate the characteristics of the channel to the transmitting station based on a downlink-frame's preamble and use correlation to detect the presence of an assigned code word. The receiving station can suppress interference from other transmitting stations in the correlation operation based on the nature of the interference signal. When the receiving station knows an interfering signal from another transmitting station, the receiving station can subtract the interfering signal before carrying out the correlation operation.
    Type: Grant
    Filed: January 16, 2009
    Date of Patent: September 4, 2012
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Rajaram Ramesh, Havish Koorapaty, Kumar Balachandran
  • Patent number: 8244305
    Abstract: Secure, digital, packet-switched, voice telephony calls are wirelessly transmitted in an efficient manner that reduces air interface bandwidth consumption by encrypting only vocoder data frames containing encoded speech, and not encrypting vocoder data frames that do not contain speech, such as those containing silence parameters. The collective reduced bandwidth consumption across a large number of voice telephony calls may allow for the admission of one or more new calls during times of voice telephony congestion. Not encrypting the silence parameters does not compromise call privacy or security, since the silence data frames do not carry any speech. The classification of encoded data frames as containing speech or not may be performed in a variety of ways.
    Type: Grant
    Filed: June 4, 2007
    Date of Patent: August 14, 2012
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Rajaram Ramesh, Kumar Balachandran, Havish Koorapaty
  • Patent number: 8233428
    Abstract: In an orthogonal frequency division multiple access communication system, a base station transmits a quick paging signal simultaneously with a synchronization signal during the same transmission symbol time period. Even though these different signals are transmitted during the same transmission symbol time period, a periodicity of the synchronization signal is maintained to facilitate rapid and cost-effective synchronization by subscriber stations with the base station. The quick paging signal alerts subscriber stations about whether to stay awake for a subsequent page or to go into a power saving sleep mode.
    Type: Grant
    Filed: February 3, 2009
    Date of Patent: July 31, 2012
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Per Ernström, Kumar Balachandran, Havish Koorapaty, Rajaram Ramesh
  • Patent number: 8223896
    Abstract: Teachings presented herein offer reduced computational complexity for symbol sequence estimation, and also provide for the generation of soft bit values representing the reliability of that estimation. A demodulator is configured to generate these soft bit values by identifying a candidate value for each symbol in the sequence which is more likely than at least one other in a defined set of candidate values. Based on the candidate value identified for each symbol, the demodulator forms a reduced set of candidate values for the symbol by selecting as many additional candidate values from the defined set as are needed to have complementary bit values for each bit value in that identified candidate value. The demodulator calculates soft bit values for the symbol sequence based on a sequence estimation process whose state space for each symbol is constrained to the corresponding reduced set.
    Type: Grant
    Filed: July 28, 2009
    Date of Patent: July 17, 2012
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Kambiz Zangi, Rajaram Ramesh