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    Method and apparatus for adaptive set management in a communication system
    92.
    发明授权
    Method and apparatus for adaptive set management in a communication system 有权

    公开(公告)号：US07054632B2

    公开(公告)日：2006-05-30

    申请号：US10007301

    申请日：2001-11-08

    申请人： Rashid Ahmed Attar ,  Rajiv Vijayan ,  Nagabhushana T. Sindhushayana

    发明人： Rashid Ahmed Attar ,  Rajiv Vijayan ,  Nagabhushana T. Sindhushayana

    IPC分类号： H04Q7/20

    CPC分类号： H04W36/18 ,  H04L1/20 ,  H04W36/30 ,  H04W52/24 ,  H04W52/26

    摘要： Methods and apparatus for an adaptive set management in a communication system are disclosed. Certain levels of an imbalance between a forward link and a reverse link are always present in a communication system. Although severe levels of an imbalance cause a detrimental effect on quality of communication and throughput, the imbalance is an issue only if it degrades throughput by one rate on the forward link. Consequently, an adaptive set management evaluates an imbalance among sectors in a subscriber station's list in accordance with the quality metric of the forward link and the reverse link, and removes from the subscriber station's list only a sector that causes severe imbalance. Although retaining a sector in the subscriber station's list may improve throughput, it may negatively affect other functions of the communication system, e.g., power control. Therefore, a method of power control is modified if a level of imbalance affecting the power control is detected.

    Frequency division multiplexing of multiple data streams in a wireless multi-carrier communication system
    93.
    发明申请
    Frequency division multiplexing of multiple data streams in a wireless multi-carrier communication system 有权
    无线多载波通信系统中多个数据流的频分复用

    公开(公告)号：US20050135308A1

    公开(公告)日：2005-06-23

    申请号：US10968614

    申请日：2004-10-18

    申请人： Rajiv Vijayan ,  Gordon Walker ,  Raghu Krishnamoorthi ,  Ramaswamy Murali

    发明人： Rajiv Vijayan ,  Gordon Walker ,  Raghu Krishnamoorthi ,  Ramaswamy Murali

    IPC分类号： H04L27/28

    CPC分类号： H04L27/0008 ,  H04L5/0007 ,  H04L5/0041 ,  H04L5/0044 ,  H04L5/0051 ,  H04L5/0064 ,  H04L25/022 ,  H04L25/0226 ,  H04L25/0228 ,  H04L27/2604 ,  H04L27/2605 ,  H04L27/2647 ,  Y02D70/10

    摘要： Techniques for multiplexing multiple data streams using frequency division multiplexing (FDM) in an OFDM system are described. M disjoint “interlaces” are formed with U usable subbands. Each interlace is a different set of S subbands, where U=M·S. The subbands for each interlace are interlaced with the subbands for each of the other M−1 interlaces. M slots may be defined for each symbol period and assigned slot indices 1 through M. The slot indices may be mapped to interlaces such that (1) frequency diversity is achieved for each slot index and (2) the interlaces used for pilot transmission have varying distances to the interlaces used for each slot index, which improves channel estimation performance. Each data stream may be processed as data packets of a fixed size, and different numbers of slots may be used for each data packet depending on the coding and modulation scheme used for the data packet.

    摘要翻译： 描述了在OFDM系统中使用频分复用（FDM）来复用多个数据流的技术。 M个不相交的“交错”与U个可用的子带形成。 每个交错是S个子带的不同集合，其中U = M.S。 用于每个交错的子带与用于其它M-1交错的每个子带进行隔行扫描。 可以为每个符号周期和分配的时隙索引1到M定义M个时隙。时隙索引可以被映射到交织，使得（1）针对每个时隙索引实现频率分集，以及（2）用于导频传输的交织具有不同的 到每个时隙索引用于交织的距离，这提高了信道估计性能。 每个数据流可以被处理为固定大小的数据分组，并且根据用于数据分组的编码和调制方案，每个数据分组可以使用不同数量的时隙。

    Local and wide-area transmissions in a wireless broadcast network
    94.
    发明申请
    Local and wide-area transmissions in a wireless broadcast network 有权
    无线广播网络中的本地和广域传输

    公开(公告)号：US20050122928A1

    公开(公告)日：2005-06-09

    申请号：US10968787

    申请日：2004-10-18

    申请人： Rajiv Vijayan ,  Fuyun Ling ,  Gordon Walker ,  Ramaswamy Murali ,  Ashok Mantravadi ,  Anand Subramaniam ,  Krishnamurthy Viswanathan

    发明人： Rajiv Vijayan ,  Fuyun Ling ,  Gordon Walker ,  Ramaswamy Murali ,  Ashok Mantravadi ,  Anand Subramaniam ,  Krishnamurthy Viswanathan

    IPC分类号： H04L12/18 ,  H04L12/56 ,  H04W74/04 ,  H04W88/08 ,  H04J3/24

    CPC分类号： H04L5/0041 ,  H04L5/0007 ,  H04L5/0044 ,  H04L5/0048 ,  H04L12/189 ,  H04W72/005

    摘要： To broadcast different types of transmission having different tiers of coverage in a wireless broadcast network, each base station processes data for a wide-area transmission in accordance with a first mode (or coding and modulation scheme) to generate data symbols for the wide-area transmission and processes data for a local transmission in accordance with a second mode to generate data symbols for the local transmission. The first and second modes are selected based on the desired coverage for wide-area and local transmissions, respectively. The base station also generates pilots and overhead information for local and wide-area transmissions. The data, pilots, and overhead information for local and wide-area transmissions are multiplexed onto their transmission spans, which may be different sets of frequency subbands, different time segments, or different groups of subbands in different time segments. More than two different types of transmission may also be multiplexed and broadcast.

    摘要翻译： 为了在无线广播网络中广播具有不同层次的不同类型的传输，每个基站根据第一模式（或编码和调制方案）处理广域传输的数据，以产生广域的数据符号 根据第二模式传输和处理用于本地传输的数据，以产生用于本地传输的数据符号。 分别基于广域和本地传输的期望覆盖来选择第一和第二模式。 基站还为本地和广域传输生成导频和开销信息。 用于本地和广域传输的数据，导频和开销信息被复用到它们的传输跨度，其可以是不同组的频率子带，不同时间段或不同时间段中的不同子带组。 多于两种不同类型的传输也可以被复用和广播。

    Access channel slot sharing
    96.
    发明授权
    Access channel slot sharing 有权
    访问通道槽共享

    公开(公告)号：US6167056A

    公开(公告)日：2000-12-26

    申请号：US189357

    申请日：1998-11-09

    申请人： David S. Miller ,  Rajiv Vijayan ,  Ephraim Zehavi ,  Jeffrey A. Levin

    发明人： David S. Miller ,  Rajiv Vijayan ,  Ephraim Zehavi ,  Jeffrey A. Levin

    IPC分类号： H04B1/707 ,  H04B7/185 ,  H04B7/216 ,  H04B7/26 ,  H04J3/06 ,  H04L7/00 ,  H04L27/30

    CPC分类号： H04B7/18532 ,  H04B1/7077 ,  H04B1/708 ,  H04B7/216 ,  H04B7/2637

    摘要： 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.

    摘要翻译： 本发明是一种通过使用多部分接入探针来增加扩频通信系统中的时隙随机接入信道上的用户容量的系统和方法。 使用短PN码序列对接入探测器的第一和第二部分进行调制，并且使用长PN码序列调制整个接入探测器。 由接入探针发送的信息在接入探针的第二部分被调制，并且发送接入探针，使得探测器的第一部分落在接入信道时隙的边界内。 在一个实施例中，用于访问信号接收的接入信道中的时隙被做成第一部分的长度。 在另一个实施例中，用于访问信号接收的多个相邻访问信道中的时隙可以比所述第一部分更长，但是在时间上彼此偏移了第一部分的长度或周期。

    Wide area and local network ID transmission for communication systems
    99.
    发明授权
    Wide area and local network ID transmission for communication systems 有权
    通信系统的广域和本地网络ID传输

    公开(公告)号：US07852822B2

    公开(公告)日：2010-12-14

    申请号：US11021310

    申请日：2004-12-22

    申请人： Michael Mao Wang ,  Bojan Vrcelj ,  Krishna Kiran Mukkavilli ,  Raghuraman Krishnamoorthi ,  Rajiv Vijayan

    发明人： Michael Mao Wang ,  Bojan Vrcelj ,  Krishna Kiran Mukkavilli ,  Raghuraman Krishnamoorthi ,  Rajiv Vijayan

    IPC分类号： H04J1/00

    CPC分类号： H04L5/0048 ,  H04L5/0007 ,  H04L5/0083 ,  H04L27/261

    摘要： The embodiments utilize OFDM symbols to communicate network IDs. The IDs are encoded into symbols utilizing the network IDs as seeds to scramble respective pilots that are then transmitted by utilizing the symbols. The pilots can be structured into a single OFDM symbol and/or multiple OFDM symbols. The single symbol structure for transmitting the network IDs is independent of the number of network ID bits and minimizes frequency offset and Doppler effects. The multiple symbol structure allows a much coarser timing accuracy to be employed at the expense of transmitting additional symbols. Several embodiments employ a search function to find possible network ID candidates from a transmitted symbol and a selection function to find an optimum candidate from a network ID candidate list.

    摘要翻译： 这些实施例利用OFDM符号来传送网络ID。 ID被编码成使用网络ID作为种子的符号，以对通过利用符号进行发送的各个导频进行加扰。 导频可以被构造成单个OFDM符号和/或多个OFDM符号。 用于发送网络ID的单个符号结构与网络ID比特数无关，并且使频偏和多普勒效应最小化。 多符号结构允许以牺牲传输附加符号为代价采用更粗糙的定时精度。 几个实施例采用搜索功能来从发送的符号和选择功能中找到可能的网络ID候选，以从网络ID候选列表中找到最佳候选。

    Method and system for selecting a best serving sector in a CDMA data communication system
    100.
    发明授权
    Method and system for selecting a best serving sector in a CDMA data communication system 有权
    用于在CDMA数据通信系统中选择最佳服务扇区的方法和系统

    公开(公告)号：US07796563B2

    公开(公告)日：2010-09-14

    申请号：US10712630

    申请日：2003-11-12

    申请人： Qiang Wu ,  Nagabhushana Sindhushayana ,  Peter J. Black ,  Rajiv Vijayan ,  Rashid Attar

    发明人： Qiang Wu ,  Nagabhushana Sindhushayana ,  Peter J. Black ,  Rajiv Vijayan ,  Rashid Attar

    IPC分类号： H04B7/216

    CPC分类号： H04W36/06 ,  H04B7/0491 ,  H04W16/24

    摘要： An apparatus for selecting a best serving sector in a code division multiple access (CDMA) communication system. A comparator compares a plurality of signal levels received from a plurality of active sectors with a signal level of a current serving sector to produce a difference. A delta generator is coupled to the comparator that generates a delta credit for each of the plurality of active sectors based on the difference. An accumulator is coupled to the delta generator and accumulates a plurality of delta credits to produce an accumulated total credit. A best sector identifier that is coupled to the accumulator identifies the best serving sector from the accumulated total credit.

    摘要翻译： 一种用于在码分多址（CDMA）通信系统中选择最佳服务扇区的装置。 比较器将从多个有效扇区接收的多个信号电平与当前服务扇区的信号电平进行比较以产生差。 增量发生器耦合到比较器，该比较器基于差异为多个活动扇区中的每一个产生增量信用。 累加器耦合到增量发生器并累积多个增量信用以产生累积的总信用。 耦合到累加器的最佳扇区标识符从累积的总信用中识别最佳服务扇区。