Patents by Inventor Herman A. Bustamante
Herman A. Bustamante 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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Patent number: 5809431Abstract: A local multipoint distribution system having a head end coupled to a plurality of base stations with each base station constituting a cell. Each base station has a plurality of sector beam antennas, each sector beam antenna illuminating a predetermined sector of the cell with RF communication signals. A plurality of RF subscriber stations for each sector of a cell, with each subscriber station having a high gain antenna with a narrow beam width oriented toward the sector beam antenna oriented toward its assigned sector. Time division multiple access control is provided at each subscriber station operated such that each subscriber transmits at a time different from the other subscribers in its sector so that the subscribers in a given sector do not interfere with each others' transmissions, respectively. The power level transmitted by the subscribers are adjusted or controlled so that the subscriber signals arrive at the respective base stations at about the same power level.Type: GrantFiled: December 6, 1995Date of Patent: September 15, 1998Assignee: Stanford Telecommunications, Inc.Inventors: Herman Bustamante, Horen Chen
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Patent number: 5748610Abstract: A wireless OCDMA communication system in which there is a cluster of base stations (BS), or radio fixed parts (RFP), which may in turn be controlled by a wireless cluster controller (WCC). The system uses frames of a time division duplex spread spectrum signal for two-way voice and/or data transmission, and a plurality of handsets, portable parts (PPs), or more complex subscribers, each adapted to communicate with the BS, or RFP, using the communication system, can be used to implement a variety of system configurations and provide a variety of at least two levels of service selected from a wide variety of services.Type: GrantFiled: May 8, 1995Date of Patent: May 5, 1998Assignee: Stanford Telecommunications, Inc.Inventors: Herman A. Bustamante, Horen Chen
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Patent number: 5734639Abstract: An exceptionally efficient operation is achieved through the use of orthogonal code divisional multiple access radio communication between a base station and a plurality of user handsets. Each user handset is provided with a local oscillator. The base station transmits a reference pilot/sounding signal which is received at the user handsets and the local oscillators at the user handsets are phase locked to the reference pilot/sounding signal.Type: GrantFiled: May 8, 1996Date of Patent: March 31, 1998Assignee: Stanford Telecommunications, Inc.Inventors: Herman Bustamante, Francis Natali, David T. Magill
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Patent number: 5687166Abstract: The OCDMA waveform of the present invention uses hi-phase PN modulation (BPSK PN chip modulation) in conjunction with MPSK or MQASK data modulation (QPSK data modulation is one preferred embodiment) to increase bandwidth efficiency. The number of orthogonal users that can be placed on a single carrier is equal to, at most, the length of the orthogonal binary sequence. The Radamacher-Walsh (RW) sequence chip rate must be 4" times the symbol rate (where n is a positive integer) since the symbol transitions must be synchronized to the RW period to guarantee orthogonality of the multiple users when data transitions are present. The symbol rate for QPSK modulation is one-half that for BPSK modulation. As a result, twice as many orthogonal functions are available for a given clock rate for QPSK as for BPSK modulation. That is, an OCDMA system with QPSK data can support twice as many users in a given bandwidth as an OCDMA system with BPSK data.Type: GrantFiled: May 31, 1995Date of Patent: November 11, 1997Assignee: Stanford Telecommunications, Inc.Inventors: Francis D. Natali, David T. Magill, Herman A. Bustamante
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Patent number: 5668795Abstract: The OCDMA waveform of the present invention uses bi-phase PN modulation (BPSK PN chip modulation) in conjunction with MPSK or MQASK data modulation (QPSK data modulation is one preferred embodiment) to increase bandwidth efficiency. The number of orthogonal users that can be placed on a single carrier is equal to, at most, the length of the orthogonal binary sequence. The Radamacher-Walsh (RW) sequence chip rate must be 4.sup.n times the symbol rate (where n is a positive integer) since the symbol transitions must be synchronized to the RW period to guarantee orthogonality of the multiple users when data transitions are present. The symbol rate for QPSK modulation is one-half that for BPSK modulation. As a result, twice as many orthogonal functions are available for a given clock rate for QPSK as for BPSK modulation. That is, an OCDMA system with QPSK data can support twice as many users in a given bandwidth as an OCDMA system with BPSK data.Type: GrantFiled: June 6, 1995Date of Patent: September 16, 1997Assignee: Stanford Telecommunications, Inc.Inventors: David T. Magill, Herman A. Bustamante, Francis D. Natali
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Patent number: 5570349Abstract: The present invention is based on novel implementation techniques which makes orthogonal CDMA practical in a short range mobile telephone environment where significant multipath fading exists. Specifically, this invention provides novel techniques for establishing the time base, frequency, and power control necessary to achieve orthogonality. Use of a high power sounding burst on the outbound link permits: 1) antenna diversity selection to minimize the probability of a faded condition, 2) local frequency locking at the subscriber terminal which avoids the requirement for a costly precision frequency standard, and 3) essentially instantaneous inbound power control based on the outbound receive signal level. This is effective since time division duplexing is used and both transmission and reception take place on the same frequency. With the short frame structure and unique placement of the sounding burst the correlation between the outbound and inbound path losses is very high.Type: GrantFiled: June 7, 1994Date of Patent: October 29, 1996Assignee: Stanford Telecommunications, Inc.Inventors: Herman Bustamante, Francis Natali, David T. Magill
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Patent number: 5548583Abstract: Base stations of a wireless telephone user location or position system are arranged in cell clusters and are mutually synchronized to provide very stable signal timing. A center cell or central base station (BSN) in a cluster of N cells acts as a cluster control center for purposes of user location or position finding and is provided with the capability to process information and derive user position. The other cells in a given cluster transmit received 911 data to the cluster control center. The handsets communicate with the respective cells in the normal fashion. However, when the handset dials "911", the enhanced 911 (ENH911) operation is initiated and the handset automatically changes its mode of operation: once per master frame there is included a 100 ms burst of a sequence of transmissions of unmodulated overlay PN sequence and Radamacher Walsh (RW) OCDMA code emanating from the handset only. However, other signalling formats may be used.Type: GrantFiled: February 15, 1995Date of Patent: August 20, 1996Assignee: Stanford Telecommuncations, Inc.Inventor: Herman A. Bustamante
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Patent number: 5375140Abstract: The present invention is directed to novel implementation techniques which makes orthogonal CDMA practical in an a short range mobile telephone environment where significant multipath fading exists. Specifically, novel techniques for establishing the time base, frequency, and power control necessary to achieve orthogonality. Use of a high power sounding burst on the outbound link permits: 1) antenna diversity selection to minimize the probability of a faded condition, 2) local frequency locking at the subscriber terminal which avoids the requirement for a costly precision frequency standard, and 3) essentially instantaneous inbound power control based on the outbound receive signal level. This is effective since time division duplexing is used and both transmission and reception take place on the same frequency. With the short frame structure and unique placement of the sounding burst the correlation between the outbound and inbound path losses is very high.Type: GrantFiled: November 24, 1992Date of Patent: December 20, 1994Assignee: Stanford Telecommunications, Inc.Inventors: Herman Bustamante, Francis Natali, David T. Magill
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Patent number: 4752967Abstract: A system for compensating for varying attenuation of an uplink signal from a local node to a satellite. The system monitors two beacon signals and the local downlink signal to determine fade. An error signal, indicating the uplink fade, is generated and utilized to adjust the gain of the uplink transmitter to compensate for the fade.Type: GrantFiled: November 29, 1985Date of Patent: June 21, 1988Assignees: Tandem Computers Incorporated, Harris CorporationInventors: Herman A. Bustamante, John A. Lemon, Harry J. Stapor
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Patent number: RE39677Abstract: A local multipoint distribution system having a head end coupled to a plurality of base stations with each base station constituting a cell. Each base station has a plurality of sector beam antennas, each sector beam antenna illuminating a predetermined sector of the cell with RF communication signals. A plurality of RF subscriber stations for each sector of a cell, with each subscriber station having a high gain antenna with a narrow beam width oriented toward the sector beam antenna oriented toward its assigned sector. Time division multiple access control is provided at each subscriber station operated such that each subscriber transmits at a time different from the other subscribers in its sector so that the subscribers in a given sector do not interfere with each others' transmissions, respectively. The power level transmitted by the subscribers are adjusted or controlled so that the subscriber signals arrive at the respective base stations at about the same power level.Type: GrantFiled: September 14, 2000Date of Patent: June 5, 2007Assignee: Alcatel USA Sourcing, L.P.Inventors: Herman Bustamante, Horen Chen