Patents Assigned to Tantivy Communications, Inc.
  • Patent number: 6369771
    Abstract: A dipole antenna for use with a mobile subscriber unit in a wireless network communications system. The antenna is fabricated with printed circuit board (PCB) photo-etching techniques for precise control of the printed structure. The dipole antenna includes a planar substrate made of dielectric material. A conductive planar element is layered on one side of the substrate in an upper region of the substrate, and a conductive planar ground patch is layered on the other side of the substrate in a lower region of the substrate. That is, the conductive planar element is stacked above the conductive planar ground patch. A feed strip is connected to the bottom of the conductive planar element, and extends from the element to a bottom edge of the substrate and terminates at a bottom feed point. Typically, the feed point is connected to a transmission line for transmitting signals to and receiving signals from the dipole antenna.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: April 9, 2002
    Assignee: Tantivy Communications, Inc.
    Inventors: Bing Chiang, Kenneth M. Gainey, Griffin K. Gothard, Christopher A. Snyder
  • Publication number: 20020036586
    Abstract: A directive antenna includes plural antenna elements in an antenna assemblage. A feed network connected to the antenna elements includes at least one switch to select a state of at least one of the antenna elements to be in an active state in response to a control signal. The other antenna elements are in a passive state, electrically coupled to an impedance to be in a reflective mode. The antenna elements in the passive state are electromagnetically coupled to the active antenna element, allowing the antenna assemblage to directionally transmit and receive signals. The directive antenna may further include an assisting switch associated with each antenna element to assist coupling the antenna elements, while in the passive state, to the respective impedances. The antenna assemblage may be circular for a 360° discrete scan in 2N directions, where N is the number of antenna elements.
    Type: Application
    Filed: May 1, 2001
    Publication date: March 28, 2002
    Applicant: Tantivy Communications, Inc.
    Inventors: Griffin K. Gothard, Bing Chiang, James A. Proctor, Kenneth M. Gainey, Joe T. Richeson
  • Publication number: 20020036595
    Abstract: A directive antenna includes plural antenna elements in an antenna assemblage. A feed network connected to the antenna elements includes at least one switch to select a state of one of the antenna elements to be in an active state in response to a control signal. The other antenna elements are in a passive state, electrically coupled to an impedance to be in a reflective mode. The antenna elements in the passive state are electromagnetically coupled to the active antenna element, allowing the antenna assemblage to directionally transmit and receive signals. The directive antenna may further include an assisting switch associated with each antenna element to assist coupling the antenna elements, while in the passive state, to the respective impedances. The antenna assemblage may be circular for a 360° discrete scan in N directions, where N is the number of antenna elements.
    Type: Application
    Filed: May 1, 2001
    Publication date: March 28, 2002
    Applicant: Tantivy Communications, Inc.
    Inventors: Bing Chiang, James A. Proctor, Griffin K. Gothard, Kenneth M. Gainey, Joe T. Richeson
  • Patent number: 6362790
    Abstract: A miniaturized directional antenna for use with system to provide data communication over wireless radio channels. The unit supports multiple antenna elements with a known orientation with respect to an earth ground plane reference. This greatly provides predictability in the steerability and other directional attributes of the antenna array using miniaturized chip multilayer or helical antenna elements, the unit may be constructed in a case or other form factor of approximately 3×3×1 inches for operation within the frequency bands around 1900 MHz.
    Type: Grant
    Filed: August 26, 1999
    Date of Patent: March 26, 2002
    Assignee: Tantivy Communications, Inc.
    Inventors: James A. Proctor, Jr., Kenneth M. Gainey
  • Publication number: 20020013135
    Abstract: An illustrative embodiment of the present invention supports the transmission of data to a user on an as-needed basis over multiple allocated data channels. Data packets are transmitted in time-slots of the allocated data channels to corresponding target receivers without the need for explicitly assigning particular time-slots to a target user well in advance of transmitting any data packets in the time-slots. Instead, each data packet transmitted in a time-slot includes a header label or preamble indicating to which of multiple possible receivers a data packet is directed. The preamble also preferably includes decoding information indicating how a corresponding data payload of the data packet is to be processed for recapturing transmitted raw data.
    Type: Application
    Filed: April 30, 2001
    Publication date: January 31, 2002
    Applicant: Tantivy Communications, Inc.
    Inventor: James A. Proctor
  • Publication number: 20020008672
    Abstract: An antenna apparatus which can increase capacity in a cellular communication system. The antenna operates in conjunction with a mobile subscriber unit and provides a plurality of antenna elements. At least one active antenna element is active and essentially centrally located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components. Through proper control of the passive antenna elements, the cellular communication system directs an antenna beam pattern toward an antenna tower of a base station to maximize gain, and, consequently, signal-to-noise ratio. Thus, optimum reception is achieved during, for example, an idle mode which receives a pilot signal. The antenna array creates a beamformer for signals to be transmitted from the mobile subscriber unit, and a directional receiving array to more optimally detect and receive signals transmitted from the base station.
    Type: Application
    Filed: May 16, 2001
    Publication date: January 24, 2002
    Applicant: Tantivy Communications, Inc.
    Inventors: Griffin K. Gothard, Alton S. Keel, Christopher A. Snyder, Bing Chiang, Joe T. Richeson, Douglas H. Wood, James A. Proctor, Kenneth M. Gainey
  • Publication number: 20020009062
    Abstract: Codes are applied to signals to reduce the number of transceivers and associated RF cabling extending from base electronics to antenna array electronics in a base station providing beam forming. The transceivers can be reduced to as few as one, and the RF cabling can be reduced to none. The codes may be orthogonal codes, such as Walsh codes. The codes are applied: to weights used to produce the beam forming, signal being transmitted or received, or both. The codes are applied a second time to decompose the coded weights/signal to associate the weights and signal with the beam forming. The coded weights/signal can be summed, including with other coded weights/signals, to produce a composite code division multiplexed signal for transmission between transceiver(s) and antenna array electronics over a single RF or non-RF cable spanning between the base electronics and array electronics.
    Type: Application
    Filed: February 23, 2001
    Publication date: January 24, 2002
    Applicant: Tantivy Communications, Inc.
    Inventors: James A. Proctor, Lawrence Wayne LaMont, George Rodney Nelson, Antoine J. Rouphael, John E. Hoffman
  • Publication number: 20010048709
    Abstract: The present invention provides for making code rate adjustments and modulation type adjustments in a pseudonoise (PN) encoded CDMA system. Coding rate adjustments may be made by changing the number of information bits per symbol, or Forward Error Code (FEC) coding rate. A forward error correction (FEC) block size is maintained at a constant amount. Therefore, as the number of information bits per symbol are increased, an integer multiple of bits per epoch is always maintained. The scheme permits for a greater flexibility and selection of effective data rates providing information bit rates ranging from, for example, approximately 50 kilobits per second to over 5 mega bits per second (Mbps) in one preferred embodiment.
    Type: Application
    Filed: January 31, 2001
    Publication date: December 6, 2001
    Applicant: Tantivy Communications, Inc.
    Inventors: John E. Hoffmann, George Rodney Nelson, Daniel I. Riley, Antoine J. Rouphael, James A. Proctor
  • Publication number: 20010036200
    Abstract: Multiple field units in a CDMA system are synchronized for communication with a base station using a shared forward and reverse link channel. Each field unit is assigned a time slot in a forward link channel to receive messages from the base station. Likewise, each field unit is assigned a time slot on a common reverse link channel for transmitting messages to the base station. Timing alignment among each of many field units and the base station is achieved by analyzing messages received at the base station in a corresponding time slot from each field unit. Thereafter, a message is transmitted in a corresponding time slot to a particular field unit from the base station for adjusting its timing so that future messages transmitted from the field unit are received in the appropriate time slot at the base station.
    Type: Application
    Filed: February 7, 2001
    Publication date: November 1, 2001
    Applicant: Tantivy Communications, Inc.
    Inventors: G. Rodney Nelson, John E. Hoffmann, Antoine J. Rouphael, James A. Proctor
  • Publication number: 20010033579
    Abstract: In an illustrative embodiment of the present invention, a first channel is allocated for transmitting sporadically generated messages from multiple field units to a base station. The first channel is preferably divided into time slots in which a field unit transmits an access request message to the base station for establishing a communication link. In response to an access request message, feedback information is provided from the base station to multiple field units indicating whether a collision was detected on the first channel for a message transmitted in a previous time slot. In an instance when a collision is detected, the field unit will re-transmit an access request message at a previous power level setting based on a random back off time.
    Type: Application
    Filed: February 23, 2001
    Publication date: October 25, 2001
    Applicant: Tantivy Communications, Inc.
    Inventors: George R. Nelson, James A. Proctor, John E. Hoffmann, Antoine J. Rouphael
  • Publication number: 20010033557
    Abstract: A scheme for assigning priority levels to users based upon a history of their request for access to the resources. If a user has, over a historical period of time, made fewer demands than a stated amount, that user is given a higher priority than a user who has made greater use of the resources than their stated amount. Thus, users making the heaviest demand on the available resources are allocated fewer resources despite their demand, whereas users that make less demands for the resources are granted more of the resources they request. An additional feature of an access allocation scheme according to the present invention is to reserve at least some resources for the users at the lowest priority levels. Thus, even users being assigned to a lowest priority queue will be granted at least some access once in a while. A third feature in connection with the present invention is to use the time of continuous transfer as a threshold to drop a presently assigned priority.
    Type: Application
    Filed: February 7, 2001
    Publication date: October 25, 2001
    Applicant: Tantivy Communications, Inc
    Inventor: Carlo Amalfitano
  • Publication number: 20010030990
    Abstract: A single, common correlation filter (CF) core is provided in a wireless system using CDMA. A plurality of channels with different data rates are provided in the wireless system. The channels provided in the wireless system include the access channel, the maintenance channel, and the traffic channel in which information (e.g., pilot or data symbols or both) is transmitted at the tier 1, tier 2 and tier 3 rates. The data rate for transmitting the information is programmable by digital signal processor (DSP). A user-unique code, such as a PN code, is applied to the information being transmitted in the channels of the wireless system. The information is QPSK modulated and transmitted in any one of the channels at any data rate. The transmitted information is correlated at the smallest data rate (i.e., the tier 1 rate) in the correlation filter (CF) of the wireless system by time multiplexing delayed versions of the PN code to the correlation filter core.
    Type: Application
    Filed: December 15, 2000
    Publication date: October 18, 2001
    Applicant: TANTIVY Communications Inc.
    Inventors: Antoine J. Rouphael, John E. Hoffmann, George Rodney Nelson, Samir K. Patel, James A. Proctor, Daniel I. Riley
  • Patent number: 6304215
    Abstract: A method for setting optimal phase settings for a plurality of antenna elements of a subscriber unit in a CDMA cellular telephone system includes the steps of detecting a received pilot signal at each of the plurality of antenna elements, combining the received pilot signal detected at each of the plurality of antenna elements with a summation circuit to produce a combined received pilot signal, determining a quality metric for the combined received pilot signal and adjusting phase settings of at least one of the plurality of antenna elements on the subscriber unit in response to the quality metric of the received pilot signal. These steps are repeated until the determined quality metric of the combined received pilot signal reaches a maximum.
    Type: Grant
    Filed: May 25, 2000
    Date of Patent: October 16, 2001
    Assignee: Tantivy Communications, Inc.
    Inventors: James A. Proctor, Jr., Kenneth M. Gainey
  • Patent number: 6301291
    Abstract: A transmitter which includes a quadrature phase shift keying (QPSK) modulator, and a receiver which includes a pilot correlation filter (PCF), a data matching filter (DMF), a timing recovery mechanism, a sampler, and a QPSK demodulator are provided in a wireless communication system. The transmitter transmits a frame of data symbols and pilot symbols to a receiver in a wireless system. The pilot symbols are inserted in the frame at known time intervals. The QPSK modulator modulates the frame of data and pilot symbols. As the receiver receives the frame of data and pilot symbols from the transmitter, the PCF recovers the pilot symbols sent by the transmitter, whereas the timing recovery mechanism tracks the timing of the pilot symbols in the frame. The DMF enhances the multipath response of the frame of data and pilot symbols at the known time intervals of the pilot symbols, and outputs a plurality of enhanced peaks.
    Type: Grant
    Filed: February 3, 2000
    Date of Patent: October 9, 2001
    Assignee: Tantivy Communications, Inc.
    Inventors: Antoine J. Rouphael, John E. Hoffmann, James A. Proctor, Jr., George Rodney Nelson, Jr.
  • Publication number: 20010026599
    Abstract: A technique for efficient implementation of pilot signals on a reverse link in a wireless communication system. An access channel is defined for the reverse link such that within each frame, or epoch, a portion is dedicated to sending only pilot symbols. Another portion of the frame is reserved for sending mostly data symbols; however, within this second portion of the frame, additional pilot symbols are interleaved among the data symbols. The pilot symbol or preamble portion of the access channel frame allows for efficient acquisition of the access signal at the base station, while providing a timing reference for determining the effects of multipath fading. In particular, a pilot correlation filter provides a phase estimate from the pilot symbols in the preamble portion, which is then used to decode the data symbols in the payload portion. An access acquisition portion of the receiver uses the phase estimates provided by the pilot correlation filter to process the output of a data symbol correlation filter.
    Type: Application
    Filed: January 19, 2001
    Publication date: October 4, 2001
    Applicant: Tantivy Communications, Inc.
    Inventors: John E. Hoffmann, George Rodney Nelson, James A. Proctor, Antoine J. Rouphael
  • Publication number: 20010021197
    Abstract: A technique for providing high speed data service over standard wireless connections via an unique integration of protocols and existing cellular signaling, such as is available with Code Division Multiple Access (CDMA) type systems through more efficient allocation of access to CDMA channels. For example, when more users exist than channels, the invention determines a set of probabilities for which users will require channel access at which times, and dynamically assigns channel resources accordingly. Channel resources are allocated according to a buffer monitoring scheme provided on forward and reverse links between a base station and multiple subscriber units. Each buffer is monitored over time for threshold levels of data to be transmitted in that buffer. For each buffer, a probability is calculated that indicates how often the specific buffer will need to transmit data and how much data will be transmitted.
    Type: Application
    Filed: January 31, 2001
    Publication date: September 13, 2001
    Applicant: Tantivy Communications, Inc.
    Inventors: Lawrence R. Foore, James A. Proctor
  • Publication number: 20010002904
    Abstract: A service option overlay for a CDMA wireless communication in which multiple allocatable subchannels are defined on a reverse link by assigning different code phases of a given long pseudonoise (PN) code to each subchannel. The instantaneous bandwidth needs of each on-line subscriber unit are then met by dynamically allocating none, one, or multiple subchannels on an as needed basis for each network layer connection. The system efficiently provides a relatively large number of virtual physical connections between the subscriber units and the base stations on the reverse link for extended idle periods such as when computers connected to the subscriber units are powered on, but not presently actively sending or receiving data. These maintenance subchannels permit the base station and the subscriber units to remain in phase and time synchronism. This in turn allows fast acquisition of additional subchannels as needed by allocating new code phase subchannels.
    Type: Application
    Filed: December 5, 2000
    Publication date: June 7, 2001
    Applicant: Tantivy Communications, Inc.
    Inventor: James A. Proctor
  • Patent number: 6236647
    Abstract: A technique for implementing a sublayer of a protocol suitable for data transfer in a multichannel environment where each channel is assumed to be prone to a significant bit error rate such as in a wireless communication system. The invention may be used to provide a high speed data transfer such as at 128 kilobits per second or higher with a bit error rate of 10−6 or better using multiple channels. By keeping track of the number of frames received in error, the sender dynamically adjusts the subframe size for each channel to optimize the effective overall throughput. The subframes each carry preferably two types of sequence numbers including a position number related to an index into a larger frame to be transmitted as a single data entity. The second sequence number is related to the subchannel used so that the receiver can detect missing subframes.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: May 22, 2001
    Assignee: Tantivy Communications, Inc.
    Inventor: Carlo Amalfitano
  • Patent number: 6222832
    Abstract: A service option overlay for a CDMA wireless communication in which multiple allocatable subchannels are defined on a reverse link by assigning different code phases of a given long pseudonoise (PN) code to each subchannel. The instantaneous bandwidth needs of each on-line subscriber unit are then met by dynamically allocating none, one, or multiple subchannels on an as needed basis for each network layer connection. The system efficiently provides a relatively large number of virtual physical connections between the subscriber units and the base stations on the reverse link for extended idle periods such as when computers connected to the subscriber units are powered on, but not presently actively sending or receiving data. These maintenance subchannels permit the base station and the subscriber units to remain in phase and time synchronism. This in turn allows fast acquisition of additional subchannels as needed by allocating new code phase subchannels.
    Type: Grant
    Filed: June 1, 1998
    Date of Patent: April 24, 2001
    Assignee: Tantivy Communications, Inc.
    Inventor: James A. Proctor
  • Patent number: 6212220
    Abstract: A method and apparatus for creating non-interfering signals to be simultaneously transmitted over a common frequency in a wireless communication systems, such as a CDMA system, without the use of orthogonal codes and/or orthogonal code generation techniques. The system provides a pseudorandom combiner that receives the information signal and a pseudorandom code sequence and combines the information signal with the pseudorandom code sequence to produce the first combined signal. A channel sequence combiner receives the first combined signal and a repetitive maximum length channel sequence and combines these signals to produce a second combined signal. A selector receives the first combined signal, the second combined signal and a repetitive strobe signal, and selects either the first combined signal or the second combined signal to produce a modulated signal based upon a value of the repetitive strobe signal.
    Type: Grant
    Filed: February 23, 1999
    Date of Patent: April 3, 2001
    Assignee: Tantivy Communications, Inc.
    Inventors: James A. Proctor, Jr., John Hoffmann, Antoine Rouphael