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    PILOT DESIGN FOR OFDM SYSTEMS WITH FOUR TRANSMIT ANTENNAS
    1.
    发明公开
    PILOT DESIGN FOR OFDM SYSTEMS WITH FOUR TRANSMIT ANTENNAS 审中-公开

    公开(公告)号：EP3709554A1

    公开(公告)日：2020-09-16

    申请号：EP20170720.5

    申请日：2006-08-22

    Applicant: Apple Inc.

    Inventor： MA, Jianglei ,  JIA, Ming ,  TONG, Wen ,  ZHU, Peiying ,  YU, Dong-Sheng ,  ZHANG, Hang ,  XU, Hua

    IPC: H04L5/00 ,  H04L25/02 ,  H04L27/26 ,  H04W74/08 ,  H04L1/06

    Abstract: A method and apparatus for improving channel estimation within an OFDM communication system. Channel estimation in OFDM is usually performed with the aid of pilot symbols. The pilot symbols are typically spaced in time and frequency. The set of frequencies and times at which pilot symbols are inserted is referred to as a pilot pattern. In some cases, the pilot pattern is a diagonal-shaped lattice, either regular or irregular. The method first interpolates in the direction of larger coherence (time or frequency). Using these measurements, the density of pilot symbols in the direction of faster change will be increased thereby improving channel estimation without increasing overhead. As such, the results of the first interpolating step can then be used to assist the interpolation in the dimension of smaller coherence (time or frequency).

    MIMO COMMUNICATION SYSTEM
    2.
    发明公开
    MIMO COMMUNICATION SYSTEM 审中-公开

    公开(公告)号：EP3641158A1

    公开(公告)日：2020-04-22

    申请号：EP19216503.3

    申请日：2006-09-29

    Applicant: Apple Inc.

    Inventor： MA, Jianglei ,  JIA, Ming ,  XU, Hua ,  TONG, Wen ,  ZHU, Peiying ,  ABDI, Moussa

    IPC: H04B7/208 ,  H04B7/005 ,  H04B7/04 ,  H04L5/00 ,  H04L1/06 ,  H04W72/04 ,  H04L27/26 ,  H04L25/02 ,  H04W88/08

    Abstract: The present invention employs a pilot scheme for frequency division multiple access (FDM) communication systems, such as single carrier FDM communication systems. A given transmit time interval will include numerous traffic symbols and two or more short pilot symbols, which are spaced apart from one another by at least one traffic symbol and will have a Fourier transform length that is less than the Fourier transform length of any given traffic symbol. Multiple transmitters will generate pilot information and modulate the pilot information onto sub-carriers of the short pilot symbols in an orthogonal manner. Each transmitter may use different sub-carriers within the time and frequency domain, which is encompassed by the short pilot symbols within the transmit time interval.; Alternatively, each transmitter may uniquely encode the pilot information using a unique code division multiplexed code and modulate the encoded pilot information onto common sub-carriers of the short pilot symbols.

    PREAMBLES IN OFDMA SYSTEM
    3.
    发明公开
    PREAMBLES IN OFDMA SYSTEM 审中-公开

    公开(公告)号：EP3537681A1

    公开(公告)日：2019-09-11

    申请号：EP19170541.7

    申请日：2005-06-23

    Applicant: Apple Inc.

    Inventor： MA, Jianglei ,  TONG, Wen ,  JIA, Ming ,  ZHU, Peiying ,  FONG, Mo-Han ,  ZHANG, Hang

    IPC: H04L27/26 ,  H04J11/00 ,  H04L7/00 ,  H04L5/00

    Abstract: The present invention provides a preamble that is inserted into an OFDMA frame and has a common sequence for all the base stations participating in a transmission. The subscriber station performs fine synchronization using the common sequence on the common preamble, and the resulting peaks will provide the locations of candidate base stations. The base station specific search is then performed in the vicinities of those peaks by using base station specific pseudo-noise sequences. With this two stage cell search, the searching window is drastically reduced. The preamble is matched to known values by a respective receiver to decode the signals and permit multiple signals to be transferred from the transmitter to the receiver. The preamble may comprise two parts, Preamble-1 and Preamble-2, which may be used in different systems, including multi-output, multi-input (MIMO) systems.

    METHOD AND SYSTEM FOR USER EQUIPMENT LOCATION DETERMINATION ON A WIRELESS TRANSMISSION SYSTEM
    6.
    发明公开
    METHOD AND SYSTEM FOR USER EQUIPMENT LOCATION DETERMINATION ON A WIRELESS TRANSMISSION SYSTEM 审中-公开

    公开(公告)号：EP3334226A1

    公开(公告)日：2018-06-13

    申请号：EP18152994.2

    申请日：2010-02-05

    Applicant: Apple Inc.

    Inventor： TEE, Lai King ,  WU, Geng ,  LI, Jun ,  TANG, Yuqiang ,  WANG, Neng ,  XU, Hua ,  MA, Jianglei

    IPC: H04W64/00

    Abstract: Neighbor cell hearability can be improved by including an additional reference signal that can be detected at a low sensitivity and a low signal-to-noise ratio, by introducing non-unity frequency reuse for the signals used for a time difference of arrival (TDOA) measurement, e.g., orthogonality of signals transmitted from the serving cell sites and the various neighbor cell sites. The new reference signal, called the TDOA-RS, is proposed to improve the hearability of neighbor cells in a cellular network that deploys 3GPP EUTRAN (LTE) system, and the TDOA-RS can be transmitted in any resource blocks (RB) for PDSCH and/or MBSFN subframe, regardless of whether the latter is on a carrier supporting both PMCH and PDSCH or not. Besides the additional TDOA-RS reference signal, an additional synchronization signal (TDOA-sync) may also be included to improve the hearability of neighbor cells.

    PREAMBLES IN OFDMA SYSTEM
    8.
    发明公开
    PREAMBLES IN OFDMA SYSTEM 审中-公开
    EMAEM系统中的PRÄAMBELN

    公开(公告)号：EP2993851A1

    公开(公告)日：2016-03-09

    申请号：EP15190774.8

    申请日：2005-06-23

    Applicant: APPLE INC.

    Inventor： MA, Jianglei ,  TONG, Wen ,  JIA, Ming ,  ZHU, Peiying ,  FONG, Mo-Han ,  ZHANG, Hang

    IPC: H04L27/26 ,  H04J11/00 ,  H04L7/00 ,  H04L5/00

    CPC classification number: H04L27/2692 ,  H04B7/02 ,  H04B7/0452 ,  H04L5/0007 ,  H04L5/0023 ,  H04L5/0048 ,  H04L7/043 ,  H04L27/2613 ,  H04L27/265 ,  H04L27/2655 ,  H04L27/2686 ,  H04W24/02

    Abstract: The present invention provides a preamble that is inserted into an OFDMA frame and has a common sequence for all the base stations participating in a transmission. The subscriber station performs fine synchronization using the common sequence on the common preamble, and the resulting peaks will provide the locations of candidate base stations. The base station specific search is then performed in the vicinities of those peaks by using base station specific pseudo-noise sequences. With this two stage cell search, the searching window is drastically reduced. The preamble is matched to known values by a respective receiver to decode the signals and permit multiple signals to be transferred from the transmitter to the receiver. The preamble may comprise two parts, Preamble-1 and Preamble-2, which may be used in different systems, including multi-output, multi-input (MIMO) systems.

    Abstract translation: 本发明提供插入到OFDMA帧中并具有参与传输的所有基站的公共序列的前同步码。 用户站使用公共前导码上的公共序列执行精细同步，并且所得到的峰值将提供候选基站的位置。 然后通过使用基站专用伪噪声序列在这些峰附近执行基站特定搜索。 通过这两个阶段的单元格搜索，搜索窗口大大减少。 前导码由相应的接收机与已知值匹配，以对信号进行解码，并允许将多个信号从发射机传送到接收机。 前导码可以包括两个部分，即前导码1和前导码2，其可以在不同的系统中使用，包括多输出多输入（MIMO）系统。

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