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22 条记录 (耗时 0.012 秒)

    ACCESS PROBE ACKNOWLEDGEMENT WITH COLLISION DETECTION
    2.
    发明公开
    ACCESS PROBE ACKNOWLEDGEMENT WITH COLLISION DETECTION 审中-公开
    ZUGANGSSONDENBESTÄTIGUNGMIT KOLLISIONSERKENNUNG

    公开(公告)号：EP1316172A2

    公开(公告)日：2003-06-04

    申请号：EP01914496.3

    申请日：2001-02-23

    申请人： Tantivy Communications, Inc.

    发明人： NELSON, George, Rodney, Jr. ,  PROCTOR, James, A., Jr. ,  HOFFMANN, John, E. ,  ROUPHAEL, Antoine, J.

    IPC分类号： H04L12/00

    CPC分类号： H04W52/242 ,  H04L1/1607 ,  H04L12/5602 ,  H04L47/14 ,  H04L47/26 ,  H04L2001/0093 ,  H04W24/00 ,  H04W52/228 ,  H04W52/48 ,  H04W52/50 ,  H04W74/0825 ,  H04W74/0858

    摘要： 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.; If no collision is detected and the base station fails to transmit an acknowledgement message from the base station to the access requesting field unit, the power output level of the field unit is increased for successive message transmissions until the message is received.

    摘要翻译： 在本发明的说明性实施例中，分配第一信道用于将来自多个现场单元的偶发生成的消息发送到基站。 第一信道优选地被划分为时隙，其中，场单元向基站发送接入请求消息以建立通信链路。 响应于访问请求消息，反馈信息从基站提供给多个字段单元，指示在第一信道上是否检测到在先前时隙中发送的消息的冲突。 在检测到冲突的情况下，场单元将基于随机退避时间在先前功率电平设置下重新发送接入请求消息; 如果没有检测到冲突，并且基站不能从基站向接入请求字段单元发送确认消息，则对于连续的消息传输增加了现场单元的功率输出电平，直到接收到消息。

    ARBITRATION METHOD FOR HIGH POWER TRANSMISSIONS IN A CODE DIVISION MULTIPLE ACCESS SYSTEM
    3.
    发明公开
    ARBITRATION METHOD FOR HIGH POWER TRANSMISSIONS IN A CODE DIVISION MULTIPLE ACCESS SYSTEM 审中-公开
    码分多址系统中高功率传输的仲裁方法

    公开(公告)号：EP1145500A1

    公开(公告)日：2001-10-17

    申请号：EP00906922.0

    申请日：2000-01-14

    申请人： Tantivy Communications, Inc.

    发明人： PROCTOR, James, A., Jr.

    IPC分类号： H04L12/28 ,  H04B7/005

    CPC分类号： H04W52/283 ,  H04W52/50 ,  H04W72/082

    摘要： In an interference mitigation method, subscribers that will receive a high power transmission generate an alert message to surrouning base stations. A surrounding base station, before it generates new transmissions, determines the distance between it and a second subscriber that will receive the new transmission. If the distance is greater than an interference threshold, the base station delays the new transmission until the first high-power transmission concludes. The method prevents two high-power transmissions from occurring simultaneously.

    摘要翻译： 在干扰减轻方法中，将接收高功率传输的用户生成警报消息以外围基站。 周围的基站在产生新的传输之前确定它与将接收新传输的第二用户之间的距离。 如果距离大于干扰门限，则基站延迟新的传输直到第一个高功率传输结束。 该方法防止两个高功率传输同时发生。

    REVERSE LINK CORRELATION FILTER IN MULTI RATE CDMA WIRELESS COMMUNICATION SYSTEMS
    6.
    发明公开
    REVERSE LINK CORRELATION FILTER IN MULTI RATE CDMA WIRELESS COMMUNICATION SYSTEMS 有权
    相关性过滤器回传信道与多个比特率的无线CDMA系统

    公开(公告)号：EP1269646A2

    公开(公告)日：2003-01-02

    申请号：EP01911096.4

    申请日：2001-02-23

    申请人： Tantivy Communications, Inc.

    发明人： ROUPHAEL, Antoine, J. ,  HOFFMANN, John, E. ,  NELSON, George, Rodney, Jr. ,  PATEL, Samir, K. ,  PROCTOR, James, A., Jr. ,  RILEY, Daniel L.

    IPC分类号： H04B1/707

    CPC分类号： H04B1/707 ,  H04B1/7105 ,  H04B1/712 ,  H04B2201/70703 ,  H04B2201/70705 ,  H04B2201/7071

    摘要： A single, common correlation filter (CF) core is provided in a wireless system using CDMA (code division multiple access). 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 (which is the basic despreading rate), tier 2 and tier 3 rates. The data rate for transmitting the information is programmable by an external programmable processor, e.g., a digital signal processor (DSP). A user-unique code, such as a PN (pseudo-random noise) code, is applied to the information being transmitted in the channels of the wireless system. Theinformation is modulated and transmitted in any one of the channels at any data rate. The transmitted information is correlated at the basic despreading 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 (or orthogonal code, Walsh code) to the correlation filter core. The correlated information is then demultiplexed and demodulated. The demodulated information is summed at the proper integer multiple of the tier 1 rate to achieve the tier 2 and tier 3 rates. One or more signal components are selected (in terms of the received power, signal-to-noise ratio or multipath width) in a window or time period for optimal information recovery. The selecting step can also be implemented according to a preprogrammed time alignment. Furthermore, outputs from the demodulated information can be provided and combined for temporal diversity. Spatial diversity is achieved by providing a plurality of antennas, and a plurality of receivers at a location and providing a single, common correlation filter at each of the plurality of antennas of the receivers in the wireless system.

    VARIABLE RATE ORTHOGONALLY CODED REVERSE LINK STRUCTURE
    7.
    发明公开
    VARIABLE RATE ORTHOGONALLY CODED REVERSE LINK STRUCTURE 审中-公开
    带可变速率正交编码式反向连接结构

    公开(公告)号：EP1155522A1

    公开(公告)日：2001-11-21

    申请号：EP00913441.2

    申请日：2000-02-11

    申请人： Tantivy Communications, Inc.

    发明人： PROCTOR, James, A., Jr. ,  HOFFMANN, John, E. ,  ROUPHAEL, Antoine, J.

    IPC分类号： H04J13/02

    CPC分类号： H04J13/004 ,  H04J13/0022 ,  H04J13/10 ,  H04J13/102

    摘要： A method and apparatus for creating non-interfering coded signals to be simultaneously transmitted over a common frequency in a wireless communication system, such as a CDMA system, at various data rates and without the use of orthogonal codes and/or orthogonal code generation techniques. The system provides cascaded arrangement of code modulations which each include a channel sequence combiner and selector. The channel sequence combiner receives an input signal and a repetitive maximum length channel sequence and combines these signals to produce a combined signal. The selector receives the input signal, the combined signal, and a repetitive strobe signal, and selects either the input signal or the combined signal to produce an encoded signal based upon a value of the repetitive strobe signal.

    ACCESS CHANNEL STRUCTURE FOR WIRELESS COMMUNICATION SYSTEM
    8.
    发明授权
    ACCESS CHANNEL STRUCTURE FOR WIRELESS COMMUNICATION SYSTEM 有权
    接入信道的结构适用于无线传输系统

    公开(公告)号：EP1256188B1

    公开(公告)日：2004-05-06

    申请号：EP01907007.7

    申请日：2001-02-05

    申请人： Tantivy Communications, Inc.

    发明人： HOFFMANN, John, E. ,  NELSON, George, Rodney, Jr. ,  PROCTOR, James, A., Jr. ,  ROUPHAEL, Antoine, J.

    IPC分类号： H04B1/707 ,  H04J3/06 ,  H04B7/26

    CPC分类号： H04L5/0046 ,  H04B1/707 ,  H04B2201/70701 ,  H04L7/041

    摘要： 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. The additional pilot symbols embedded in the payload portion are used in a cross product operation to further resolve the effects of multipath fading.

    MAINTENANCE LINK USING ACTIVE/STANDBY REQUEST CHANNELS
    9.
    发明公开
    MAINTENANCE LINK USING ACTIVE/STANDBY REQUEST CHANNELS 有权
    维护与积极和READINESS操作查询渠道

    公开(公告)号：EP1256192A2

    公开(公告)日：2002-11-13

    申请号：EP01910446.2

    申请日：2001-02-07

    申请人： Tantivy Communications, Inc.

    发明人： NELSON, G., Rodney, Jr. ,  HOFFMANN, John, E. ,  ROUPHAEL, Antoine, J. ,  PROCTOR, James, A., Jr.

    IPC分类号： H04B7/26

    CPC分类号： H04W56/0085 ,  H04B7/2637

    摘要： Multiple field units in a CDMA system are synchronized for communication with a base station using shared forward and reverse link channels. In an illustrative embodiment, 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 and power level control 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 as transmitted by each field unit. Thereafter, a message is transmitted from the base station in a corresponding time slot to a particular field unit for adjusting its timing or power level so that future messages transmitted from the field unit are received in the appropriate time slot at the base station at a desired power level. In this way, minimal resources are deployed to maintain communication and precise synchronization between a base station and each of multiple users, minimizing collisions between field units transmitting in adjacent time slots on the reverse link. This method reduces the frequency a field unit must rely on the use of a slotted aloha random access channel according to IS-95.