Patents by Inventor Ephraim Zehavi

Ephraim Zehavi 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: 20050053030
    Abstract: A method and apparatus for transmitting digital data in a cellular environment. Adjacent cells of the cellular system are prevented from simultaneously transmitting data. Because the noise from transmissions of adjacent cells is a primary source of interference, the transmission rate of power limited base stations can be dramatically increased when the noise from adjacent cells is eliminated. The transmissions to each subscriber station are made at a fixed transmission power level. However, the data rate of transmitted signals differs from one subscriber station to another depending the path loss differences. In a first exemplary embodiment, the data rate of transmissions to a subscriber station is determined by selecting an encoding rate for the transmitted signal while holding the symbol rate constant.
    Type: Application
    Filed: September 14, 2004
    Publication date: March 10, 2005
    Inventor: Ephraim Zehavi
  • Patent number: 6745018
    Abstract: An active cancellation device receives a model of a first signal from a local wireless transmitter. The first signal causes a coupled signal that interferes in a second signal received by a local wireless receiver from a remote wireless transmitter. The active cancellation device generates a cancellation signal based on the model of the first signal, and provides the cancellation signal to the local wireless receiver. At the local wireless receiver, the cancellation signal combines with the coupled signal and the second signal. The cancellation signal reduces the interference in the second signal caused by the coupled signal.
    Type: Grant
    Filed: September 29, 2000
    Date of Patent: June 1, 2004
    Assignee: Intel Corporation
    Inventors: Ephraim Zehavi, Robert P. Gilmore, Robert Wentworth, James Gilb
  • Patent number: 6717908
    Abstract: In an orthogonal frequency division multiplexing (OFDM) system which uses an outer Reed-Solomon encoder and interleaver an inner convolutional encoder, after the inner convolutional encoding the data bits are interleaved, and then grouped into symbols, each symbol having “m” bits. After grouping, the symbols are mapped to a complex plane using quadrature amplitude modulation (QAM). Thus, bits, not symbols, are interleaved by the inner interleaver. A receiver performs a soft decision regarding the value of each bit in each complex QAM symbol received.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: April 6, 2004
    Assignee: Qualcomm, Incorporated
    Inventors: Rajiv Vijayan, Joseph P. Odenwalder, Jack K. Wolf, Chong U. Lee, Ephraim Zehavi
  • Publication number: 20030214961
    Abstract: A wireless device is provided with a first wireless transceiver and a second wireless transceiver operative in a coordinated manner and coupled to at least one controller manager. The first wireless transceiver transmits and receives signals in accordance with a first protocol to and from a first network device of a first wireless network communicatively coupled to the apparatus, and the second wireless transceiver transmits and receives signals in accordance with a second protocol to and from a second network device of a second wireless network communicatively coupled to the apparatus. The wireless device is further provided with a network manager to coordinate the transmit and receive operations of the first wireless transceiver and said the second wireless transceiver in order to enable the wireless device to communicate contemporaneously with the first and second wireless networks.
    Type: Application
    Filed: June 17, 2003
    Publication date: November 20, 2003
    Inventors: Ron Nevo, Ephraim Zehavi, Brett A. Monello, Ran Ginosar
  • Patent number: 6600726
    Abstract: A wireless device is provided with at least one wireless transceiver and at least one controller manager to transmit and receive signals wirelessly to and from network devices of a first and second wireless network, in a coordinated manner, in accordance with a first and a second protocol respectively. The wireless device is further provided with a network manager to coordinate the network devices of the first and second wireless networks to reduce interference between the network devices of the two wireless networks. In various embodiments, the reduction is effectuated through proactive avoidance of interference with dominant devices by dominated devices, whenever an interference is predicted to occur. In other embodiments, the reduction is effectuated through corresponding application of appropriate filtering to correspondingly cancel the respective interfering signals, whenever an interference is predicted to occur.
    Type: Grant
    Filed: November 12, 1999
    Date of Patent: July 29, 2003
    Assignee: Mobilian Corporation
    Inventors: Ron Nevo, Ephraim Zehavi, Brett A. Monello, Ran Ginosar
  • Patent number: 6553538
    Abstract: In a communication system which conforms to the IS-99 standard, a concatenated code is used to provide for error free file transfer over the air. The concatenated code comprises Reed-Solomon coding, CRC block coding, and convolutional coding. The file is partitioned into data frames and Reed-Solomon encoding is performed on the data frames. CRC block encoding is then performed on the Reed-Solomon encoded data. The CRC encoded data is convolutionally encoded. The CRC block encoding and convolutional encoding are performed in accordance with the IS-99 standard. The additional Reed-Solomon encoding step provides improved error correction capability while maintaining compatibility with the IS-99 standard. At the receiver, Reed-Solomon decoding is performed if the number of erasures in a code word is less than or equal to (n−k) or the symbol errors in a code word is less than or equal to (n−k)/2. Otherwise, a request for retransmission is sent.
    Type: Grant
    Filed: February 14, 2001
    Date of Patent: April 22, 2003
    Assignee: Qualcomm Incorporated
    Inventor: Ephraim Zehavi
  • Publication number: 20030053432
    Abstract: A method and apparatus for transmitting digital data in a cellular environment. Adjacent cells of the cellular system are prevented from simultaneously transmitting data. Because the noise from transmissions of adjacent cells is a primary source of interference, the transmission rate of power limited base stations can be dramatically increased when the noise from adjacent cells is eliminated. The transmissions to each subscriber station are made at a fixed transmission power level. However, the data rate of transmitted signals differs from one subscriber station to another depending the path loss differences. In a first exemplary embodiment, the data rate of transmissions to a subscriber station is determined by selecting an encoding rate for the transmitted signal while holding the symbol rate constant.
    Type: Application
    Filed: October 11, 2002
    Publication date: March 20, 2003
    Applicant: QUALCOMM Incorporated
    Inventor: Ephraim Zehavi
  • Publication number: 20030054755
    Abstract: A method and apparatus for processing a received signal carrying data via multiple subcarriers at respective subcarrier frequencies is disclosed herein. The method includes assessing jamming interference on the subcarrier frequencies. In response to the assessed interference, respective reliability metrics are assigned to the subcarriers. The signal is then demodulated using the reliability metrics so as to recover the data.
    Type: Application
    Filed: March 8, 2002
    Publication date: March 20, 2003
    Inventors: Ephraim Zehavi, Ido Bettesh
  • Patent number: 6496543
    Abstract: A method and apparatus for transmitting digital data in a cellular environment. Adjacent cells of the cellular system are prevented from simultaneously transmitting data. Because the noise from transmissions of adjacent cells is a primary source of interference, the transmission rate of power limited base stations can be dramatically increased when the noise from adjacent cells is eliminated. The transmissions to each subscriber station are made at a fixed transmission power level. However, the data rate of transmitted signals differs from one subscriber station to another depending the path loss differences. In a first exemplary embodiment, the data rate of transmissions to a subscriber station is determined by selecting an encoding rate for the transmitted signal while holding the symbol rate constant.
    Type: Grant
    Filed: October 29, 1996
    Date of Patent: December 17, 2002
    Assignee: Qualcomm Incorporated
    Inventor: Ephraim Zehavi
  • Publication number: 20020106015
    Abstract: A method and apparatus for transmitting digital data in a cellular environment. Adjacent cells of the cellular system are prevented from simultaneously transmitting data. Because the noise from transmissions of adjacent cells is a primary source of interference, the transmission rate of power limited base stations can be dramatically increased when the noise from adjacent cells is eliminated. The transmissions to each subscriber station are made at a fixed transmission power level. However, the data rate of transmitted signals differs from one subscriber station to another depending the path loss differences. In a first exemplary embodiment, the data rate of transmissions to a subscriber station is determined by selecting an encoding rate for the transmitted signal while holding the symbol rate constant.
    Type: Application
    Filed: March 29, 2002
    Publication date: August 8, 2002
    Inventor: Ephraim Zehavi
  • Publication number: 20020040383
    Abstract: Apparatus for customer service includes at least one wireless communication terminal, adapted to be deployed at a first location in a facility that is visited by customers, so as to receive digital data over a wireless link from a portable device carried by at least one of the customers in a vicinity of the terminal. A service center, at a second location, which is not in the vicinity of the at least one wireless communication terminal, is in communication with the terminal so as to receive the digital data therefrom and to generate a permanent record of the data for delivery to the at least one of the customers.
    Type: Application
    Filed: April 12, 2001
    Publication date: April 4, 2002
    Inventor: Ephraim Zehavi
  • Publication number: 20010030939
    Abstract: In an orthogonal frequency division multiplexing (OFDM) system which uses an outer Reed-Solomon encoder and interleaver an inner convolutional encoder, after the inner convolutional encoding the data bits are interleaved, and then grouped into symbols, each symbol having “m” bits. After grouping, the symbols are mapped to a complex plane using quadrature amplitude modulation (QAM). Thus, bits, not symbols, are interleaved by the inner interleaver. A receiver performs a soft decision regarding the value of each bit in each complex QAM symbol received.
    Type: Application
    Filed: May 10, 2001
    Publication date: October 18, 2001
    Applicant: Qualcomm, Incorporated
    Inventors: Rajiv Vijayan, Joseph P. Odenwalder, Jack K. Wolf, Chong U. Lee, Ephraim Zehavi
  • Publication number: 20010024432
    Abstract: A variable rate transmission system where a packet of variable rate data is transmitted on a traffic channel if the capacity of the traffic channel is greater than or equal to the data rate of the packet. When the rate of the packet of variable rate data exceeds the capacity of the traffic channel, the packet is transmitted on a traffic channel and at least one overflow channel. Also described is a receiving system for receiving and reassembling the data transmitted on the traffic channel and at least one additional overflow channel.
    Type: Application
    Filed: May 8, 2001
    Publication date: September 27, 2001
    Applicant: Qualcomm, Incorporated
    Inventors: Ephraim Zehavi, David S. Miller, Judith LaRocca
  • Patent number: 6292476
    Abstract: A variable rate receiving system where a packet of variable rate data is reassembled on a traffic channel if the capacity of the traffic channel is greater than or equal to the data rate of the packet. When the rate of the packet of variable rate data exceeds the capacity of the traffic channel, the packet is received on a traffic channel and at least one overflow channel. Also described is a transmission system for transmitting the data on the traffic channel and at least one additional overflow channel.
    Type: Grant
    Filed: September 24, 1997
    Date of Patent: September 18, 2001
    Assignee: Qualcomm Inc.
    Inventors: Ephraim Zehavi, David S. Miller, Judith LaRocca
  • Publication number: 20010021195
    Abstract: The present invention is a system and method for increasing user capacity on a slotted random access channel in a spread spectrum communications system by using a multi-part access probe. First and second parts of the access probe are modulated using a short PN code sequence, and the entire access probe is modulated using a long PN code sequence. Information to be transmitted by the access probe is modulated on the second part of the access probe, and the access probe is transmitted so that the first part of the probe falls within the boundaries of an access channel slot. In one embodiment, time slots in access channels used for access signal reception are made the length of the first part. In a further embodiment, time slots in a plurality of adjacent access channels used for access signal reception may be longer than said first part but are offset in time from each other by the length or period of the first part.
    Type: Application
    Filed: December 26, 2000
    Publication date: September 13, 2001
    Inventors: David S. Miller, Rajiv Vijayan, Jeffrey A. Levin, Ephraim Zehavi
  • Patent number: 6282168
    Abstract: In an orthogonal frequency division multiplexing (OFDM) system which uses an outer Reed-Solomon encoder and interleaver an inner convolutional encoder, after the inner convolutional encoding the data bits are interleaved, and then grouped into symbols, each symbol having “m” bits. After grouping, the symbols are mapped to a complex plane using quadrature amplitude modulation (QAM). Thus, bits, not symbols, are interleaved by the inner interleaver. A receiver performs a soft decision regarding the value of each bit in each complex QAM symbol received.
    Type: Grant
    Filed: November 2, 1999
    Date of Patent: August 28, 2001
    Assignee: Qualcomm Inc.
    Inventors: Rajiv Vijayan, Joseph P. Odenwalder, Jack K. Wolf, Chong U. Lee, Ephraim Zehavi
  • Publication number: 20010004761
    Abstract: In a communication system which conforms to the IS-99 standard, a concatenated code is used to provide for error free file transfer over the air. The concatenated code comprises Reed-Solomon coding, CRC block coding, and convolutional coding. The file is partitioned into data frames and Reed-Solomon encoding is performed on the data frames. CRC block encoding is then performed on the Reed-Solomon encoded data. The CRC encoded data is convolutionally encoded. The CRC block encoding and convolutional encoding are performed in accordance with the IS-99 standard. The additional Reed-Solomon encoding step provides improved error correction capability while maintaining compatibility with the IS-99 standard. At the receiver, Reed-Solomon decoding is performed if the number of erasures in a code word is less than or equal to (n−k) or the symbol errors in a code word is less than or equal to (n−k)/2. Otherwise, a request for retransmission is sent.
    Type: Application
    Filed: February 14, 2001
    Publication date: June 21, 2001
    Inventor: Ephraim Zehavi
  • Patent number: 6212659
    Abstract: In a communication system which conforms to the IS-99 standard, a concatenated code is used to provide for error free file transfer over the air. The concatenated code comprises Reed-Solomon coding, CRC block coding, and convolutional coding. The file is partitioned into data frames and Reed-Solomon encoding is performed on the data frames. CRC block encoding is then performed on the Reed-Solomon encoded data. The CRC encoded data is convolutionally encoded. The CRC block encoding and convolutional encoding are performed in accordance with the IS-99 standard. The additional Reed-Solomon encoding step provides improved error correction capability while maintaining compatibility with the IS-99 standard. At the receiver, Reed-Solomon decoding is performed if the number of erasures in a code word is less than or equal to (n−k) or the symbol errors in a code word is less than or equal to (n−k)/2. Otherwise, a request for retransmission is sent.
    Type: Grant
    Filed: April 7, 1999
    Date of Patent: April 3, 2001
    Assignee: Qualcomm Inc.
    Inventor: Ephraim Zehavi
  • Patent number: 6185199
    Abstract: In a time gated frequency division duplexing (FDD) data communication system, the base station transmits two data frames on the forward link to the first remote station and receives two data frames on the reverse link from the second remote station at the first time frame. At the second time frame, the base station transmits two data frames to the second remote station and receives two data frames from the first remote station. Data transmission and reception alternate over consecutive time frames. On the forward link, each data frame is covered with a unique Walsh code. The data is also spread with the short PNI and PNQ codes in accordance with the IS-95A standard. The data can be scrambled by the long PN code. The base station delays the long PN code and short PN codes and properly loads the Walsh codes so that the processed data can be properly demodulated and descrambled by the destination remote station.
    Type: Grant
    Filed: July 23, 1997
    Date of Patent: February 6, 2001
    Assignee: Qualcomm Inc.
    Inventor: Ephraim Zehavi
  • Patent number: RE38010
    Abstract: An encoder for encoding data as trellis coded data and a decoder for decoding the trellis coded data. The encoder uses a rate ½ convolutional encoder punctured to a rate k/n to produce n symbols from k input bits. The symbols are converted by a converter to sets of p symbols and provided to an interleaver. In the interleaver certain ones of the symbols are delayed. Symbol sets are output from the interleaver to a 2P-ary modem for modulation and transmission. The decoder uses a modem for providing from the modulated data sets of p symbols. A deinterleaver delays certain ones of the symbols to achieve time alignment of the originally interleaved symbols. The sets of time aligned symbols are provided to metric calculators for computing signal metrics which are provided to a converter for providing n sets of metrics to a metric decoder. The metric decoder computes from the n sets of metrics an estimate of the encoded k data bits.
    Type: Grant
    Filed: May 4, 1999
    Date of Patent: February 25, 2003
    Assignee: Qualcomm, Incorporated
    Inventors: Ephraim Zehavi, Jack K. Wolf