Abstract: A system and method for acknowledging receipt of messages within a packet based communication network. A sending node generates a data packet within an upper layer, and transmits the data packet to a receiving node using a lower layer. The lower layer generates and transmits a pseudo reply packet to the upper layer in response to an acknowledgment received from the receiving node. The pseudo reply packet notifies the upper layer of the sending node that the receiving node successfully received the data packet and removes the burden of having an upper layer of the receiving node generate an actual reply packet.
Type:
Grant
Filed:
May 8, 1998
Date of Patent:
May 21, 2002
Assignee:
Fujitsu Limited
Inventors:
Takeshi Shimizu, Wolf-Dietrich Weber, Patrick J. Helland, Thomas M. Wicki, Winfried W. Wilcke
Abstract: A radio communication system having a base station and a plurality of radio terminals, wherein each radio terminal having a transmission request transmits a reservation packet at arbitrary timing through a reservation channel in accordance with a CDMA scheme, and the base station assigns a traffic channel and a time slot to be used to each radio terminal requesting a reservation through a reply packet outputted onto a reply channel. On the reservation channel, a short spreading code corresponding to a matched filter is applied.
Type:
Grant
Filed:
February 24, 2000
Date of Patent:
May 21, 2002
Assignee:
Hitachi, Ltd.
Inventors:
Hironari Masui, Yasuo Ohgoshi, Takashi Yano, Nobukazu Doi
Abstract: A receiving circuit of a mobile communication terminal which can prevent the deterioration of receiving sensitivity caused by an intermodulation product signal. The receiving circuit includes a front-end receiver, a controller, and a feed forward linearizer having an intermodulation product generator, a phase shifter and a variable attenuator. The feed forward linearizer generates an internodulation product signal in a feed forward path having the same magnitude as an intermodulation product signal in a main path, generated from the front-end receiver, but with a 180° phase difference. As a result, the intermodulation product signals are eliminated via vectorial addition of the signals in the main and feed forward paths.
Abstract: The present invention is a novel and improved method and apparatus for transmitting data in a multiple carrier CDMA communication system. In the first implementation of the present invention, the data is encoded and the resulting encoded symbols are divided up and transmitted on different frequencies. The encoded symbols are provided to a symbol repetition means which keeps the symbol rate of data to be transmitted fixed. In a second embodiment, no symbol repetition is provided and variable length Walsh sequences are used to handle data rate variations.
Abstract: The invention relates to a direct data access (DDA) from a digital mobile network to a data network in a centralized manner in a first mobile switching center (MSC2). Another switching center (MSCI) is arranged to route a mobile data call, addressed to the centralized DDA, to MSC2 as a digital call according to a bearer service (UDI) supported by the mobile network. The interworking function of the routed data call are divided between the MSCs. MSC2 comprises a first interworking function (IWF2) that provides the adaptation functions required by the centralized DDA and the digital bearer service. MSC1 comprises a second interworking function (IWFI) providing the adaptation functions required by the radio connection and the digital bearer service.
Abstract: A broadcast control system and its components capable of determining unique routes to deliver broadcast cells to every destination in an ATM network, which is designed to avoid network congestion and subsequent degradation in quality of service, as well as to reduce the workloads imposed on network equipment. The ATM network is organized by a plurality of network elements and at least one service provider terminal connected to a source network element. A broadcast routing controller disposed in the source network element distributes a broadcast routing control cell over the ATM network. Each network element on the network receives this broadcast routing control cell as well as its replicas delivered through different paths, and on the basis of information contained in those control cells, it establishes its own routing data in the local storage. This routing data indicates a particular link that is connected to the shortest path between the source network element and the present network element.
Abstract: A communication server maintains profile information on twisted pair lines in a profile table. This profile information may be generated in a training session and then retrieved to train a modem or transceiver unit to communicate data over the associated twisted pair line using XDSL communication techniques.
Type:
Grant
Filed:
January 8, 1998
Date of Patent:
May 7, 2002
Assignee:
Cisco Technology, Inc.
Inventors:
John F. McHale, Robert H. Locklear, Jr., James R. Sisk
Abstract: A data transmission apparatus of an orthogonal frequency multiplex modulation system wherein data is transmitted using a plurality of carriers which are in a mutually orthogonal relationship with one another. The apparatus includes a transmitter which previously inserts a group of predetermined synchronization symbols into an OFDM modulated transmission signal every fixed period and a receiver which demodulates a received OFDM modulated transmission signal to a baseband OFDM signal. In the receiver, an absolute value of an A/D converted digital signal is taken and the signal is bandwidth-limited to a predetermined band width. Then, it is decided whether an amplitude of the signal is larger than or smaller than a predetermined value and a decision result thereof is produced. A null section in the synchronization symbol group is detected on the basis of the decision result and a start point of another synchronization symbol subsequent to the null section is further detected.
Abstract: A system which determines whether to accept a wireless connection to a network device receives a request to initiate the wireless connection to the network device, and then determines, in response to the request, a nominal cell rate at which cells are exiting from a buffer in the network device for the requested wireless connection. Thereafter, the system determines an amount of buffer space in the network device required to accommodate the connection, and decides whether to accept the wireless connection based on the nominal cell rate and the amount of buffer space required to accommodate the connection.
Abstract: A system, device, and method for evaluating dynamic range in a communication system utilizes a narrow band multiple tone test signal for emulating a wide band composite signal equivalent to the symbol rate bandwidth of a digitally modulated carrier. The multiple tone test signal is constructed such that a significant portion of the third order intermodulation distortion products fall within the channels adjacent to the test channel so that the dynamic range can be evaluated with a commercially available industry standard CATV analyzer using a standard adjacent channel power measurement technique.
Type:
Grant
Filed:
August 29, 1997
Date of Patent:
April 23, 2002
Assignee:
Motorola, Inc.
Inventors:
John L. Moran, III, Bruce O. Cox, William Leslie Brown
Abstract: A transmitter is provided for simultaneously transmitting a plurality of signals in a plurality of directive beams to corresponding destination stations, each destination station located in a separate fan within a service area. The transmitter includes a plurality of beamformers, each beamformer receiving one of the signals to be transmitted to an associated fan, each of the beamformers having a plurality of outputs for each different signal to be transmitted. A plurality of Butler matrices each receive one of the plurality of outputs from the plurality of beamformers for each different signal to be transmitted, each Butler matrix having a plurality of outputs in phased relationship to one another, wherein each of the signals to be transmitted is simultaneously provided across the outputs of each Butler matrix in a phased relationship.
Abstract: An improved technique for connecting calls through a telephone network is disclosed wherein a data signal transmitted from a computer over- a separate network is used to instruct the telephone switch to make the desired connection.
Abstract: A wireless telephone system and related method are described, the system having a plurality of wireless handsets and a base unit, the base unit having a base transceiver, each handset having a handset transceiver for establishing a wireless link over a shared channel with the base unit via the base transceiver. The base unit transmits a signal comprising a current packet of a plurality of packets of an epoch. Each handset transceiver has a receiver having a parallel correlator for generating timing error signals and end-of-packet signals for the signal, and a timing loop for receiving the timing error signals and for establishing symbol-level timing synchronization. An enable resynch gate of the receiver receives the end-of-packet signals from the parallel correlator to establish packet-level synchronization, and a de-packetizer of the receiver reads epoch location information from the current packet which identifies the location of the current packet within the epoch.
Type:
Grant
Filed:
December 29, 1998
Date of Patent:
April 9, 2002
Assignee:
Thomson Licensing S. A.
Inventors:
Paul Gothard Knutson, Kumar Ramaswamy, Dong-Chang Shiue
Abstract: A method of interconnecting a CDMA cellsite having signal advancing capabilities with at least one remote microcell without re-synchronization capabilities. The method of the present invention sufficiently advances the signal to compensate for the time delay induced by communication signal travel over a fiber optic connection between a base station cellsite and a remote microcell.
Type:
Grant
Filed:
June 1, 1998
Date of Patent:
April 2, 2002
Assignee:
Ameritech Corporation
Inventors:
Brian Douglas Fiut, Timothy Jason Joyce
Abstract: A multiplexed data producing apparatus which multiplexes N (integer) pieces of object data in which one of video data, audio data, and digital data is multiplexed to produce one piece of multiplexed data comprises a temporal storage means for temporarily storing the N pieces of object data; a control means for controlling synchronization of time information of each object data for each temporarily stored object data; and a multiplexing means for multiplexing the processed object data to produce multiplexed data.
Type:
Grant
Filed:
July 7, 1997
Date of Patent:
March 19, 2002
Assignee:
Matsushita Electric Industrial Co., Ltd.
Abstract: The present invention provides a method for reliable stale packet recognition in a network. The method includes: rewriting a packet's transaction identifier (TID) such that the rewritten TID is not a same TID as a previous transaction if the packet could be erroneously seen as a duplicate packet by the receiving router; sending the packet to the receiving router; and blocking the sent packet from transmission to the receiving node if a transaction timer has expired and if the sent packet's TID is the same TID as the previous transaction. The method blocks duplicate packets which arrive at the receiving router after the expiration of the transaction timer. When a packet for a new transaction to be sent to the receiving node is assigned the same TID as the previous transaction, the sending router rewrites the packet's TID to avoid the erroneous recognition of this packet as a duplicate by the receiving router.
Abstract: A localized wireless gateway system provides wireless telephone communication, and for at least interexchange communication, provides voice telephone access to a public packet data network, such as the Internet. The wireless gateway system includes base station transceivers and a packet service gateway coupling the transceivers to the public packet data network. The packet service gateway compresses and decompresses voice frequency communication signals, and it sends and receives the compressed signals in packet form via the network. The packet service gateway also provides for signaling through the network to establish two-way voice communication sessions. In the preferred implementation, the localized wireless gateway system includes at least one radio port control unit coupled to the base station transceivers for controlling calls through the transceivers.
Abstract: A modified UTOPIA interface for inter-board applications is provided where the address timing generated by a polling master is extended to be two clock cycles long with no NULL address being driven onto the address line in between addresses. Output and input circuitry is provided in conjunction with the polling master and user ATM boards to accommodate hot insertion and to help drive the circuit. The master preferably includes an outgoing address latch and address latch control associated with the address bus, and a register associated with the enable signal. The master also includes a hot insertion buffer on the incoming cell available signal. The user device(s) include hot insertion buffers on the address bus, the data bus, and the enable signal. A remapping function is also preferably provided in associated with the user board which permits the user board to map received addresses into desired addresses.
Abstract: A method and system are disclosed whereby a mobile phone user can select one or more service preferences for the mobile phone from a simulated mobile phone display on an Internet web page. The user can access the web page from a personal or business computer. Once the selection has been made, the user can save the preferences to a server in the mobile phone network. The server contains (or provides links to) the full complement of services that are available for selection. The selected services' applications are downloaded from the server to the mobile phone (via the network) either immediately (if a network connection is already made) or the next time the phone is turned on. Consequently, the user can readily obtain the services desired, and also customize the display and “look and feel” of the mobile phone.
Abstract: A probing device for resolving the limitations of fabric registration by providing a fabric with a system and method for concurrently probing multiple end-devices, which would otherwise be unusable to register with the fabric, to registration information. In addition, by relying upon the probing device, a fabric can avoid requiring any end-devices from having to initiate registration with the fabric.
Type:
Grant
Filed:
June 19, 1998
Date of Patent:
March 5, 2002
Assignee:
Brocade Communications Systems, Inc.
Inventors:
Jieming Zhu, Paul Ramsay, Vince Guan, Kha Sin Teow