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公开(公告)号：US11032119B2
公开(公告)日：2021-06-08
申请号：US16780620
申请日：2020-02-03
Applicant: Apple Inc.
Inventor： Jianglei Ma , Wen Tong , Ming Jia , Hua Xu , Peiying Zhu , Hang Zhang
Abstract: Methods and systems are provided that enable an OFDM transmitter to be used for transmitting conventional OFDM or a form of transformed OFDM. A technique is provided for transforming a coded and modulated sequence of samples prior to an IFFT that enables the transformed sequence of samples to be transmitted using conventional OFDM or transformed OFDM. The selection of a transform function for transforming the coded and modulated sequence of samples may be based on optimizing the transform function for particular operating conditions between the transmitter and receiver. In some embodiments of the invention OFDM and time transformed OFDM are multiplexed in time and/or frequency in a transmission frame. In some embodiments of the invention a pilot pattern is provided in which the pilot are sent using OFDM and data is sent using OFDM and/or transformed OFDM.
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公开(公告)号：US20200119827A1
公开(公告)日：2020-04-16
申请号：US16716845
申请日：2019-12-17
Applicant: Apple Inc.
Inventor： Jianglei Ma , Ming Jia , Wen Tong , Peiying Zhu , Hua Xu , Hang Zhang , Mo-Han Fong
Abstract: In some embodiments of the invention, OFDM symbols are transmitted as a plurality of clusters. A cluster includes a plurality of OFDM sub-carriers in frequency, over a plurality of OFDM symbol durations in time. Each cluster includes data as well as pilot information as a reference signal for channel estimation. In some embodiments, a plurality of clusters collectively occupy the available sub-carrier set in the frequency domain that is used for transmission. In some embodiments of the invention data and/or pilots are spread within each cluster using code division multiplexing (CDM). In some embodiments pilots and data are separated by distributing data on a particular number of the plurality of OFDM symbol durations and pilots on a remainder of the OFDM symbol durations. CDM spreading can be performed in time and/or frequency directions.
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公开(公告)号：US10595249B2
公开(公告)日：2020-03-17
申请号：US15982089
申请日：2018-05-17
Applicant: Apple Inc.
Inventor： Jianglei Ma , Ming Jia , Peiying Zhu , Wen Tong
IPC: H04W36/08 , H04B7/06 , H04L5/00 , H04L27/26 , H04J11/00 , H04B7/022 , H04L7/00 , H04B7/0413 , H04B7/04
Abstract: A method and apparatus are provided for performing acquisition, synchronization and cell selection within an MIMO-OFDM communication system. A coarse synchronization is performed to determine a searching window. A fine synchronization is then performed by measuring correlations between subsets of signal samples, whose first signal sample lies within the searching window, and known values. The correlations are performed in the frequency domain of the received signal. In a multiple-output OFDM system, each antenna of the OFDM transmitter has a unique known value. The known value is transmitted as pairs of consecutive pilot symbols, each pair of pilot symbols being transmitted at the same subset of sub-carrier frequencies within the OFDM frame.
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公开(公告)号：US10560159B2
公开(公告)日：2020-02-11
申请号：US16151636
申请日：2018-10-04
Applicant: Apple Inc.
Inventor： Jianglei Ma , Ming Jia , Hua Xu , Wen Tong , Peiying Zhu , Moussa Abdi
IPC: H04W4/00 , H04B7/0452 , H04L5/00 , H04L27/26 , H04W72/04 , H04B7/0413 , H04W88/08 , H04J13/18 , H04L1/06 , H04L25/02 , H04J13/16
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.
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115.发明授权公开(公告)号：US10470164B2
公开(公告)日：2019-11-05
申请号：US13784158
申请日：2013-03-04
Applicant: Apple Inc.
Inventor： Hang Zhang , Jianglei Ma , Ming Jia , Mo-Han Fong , Peiying Zhu , Wen Tong
IPC: H04W72/04 , H04W72/00 , H04W74/00 , H04L12/18 , H04W4/08 , H04W48/10 , H04B7/0413 , H04L1/18 , H04L27/26 , H04L29/12 , H04L5/02
Abstract: A method and system for allocating shareable wireless transmission resources. A resource pool is established. The resource pool is divided into a plurality of physical layer allocation units usable for wirelessly transmitting control information and traffic data. The allocation units are assigned at the media access control layer for the wireless transmission of the control information and traffic data. The system and method of the present invention also allows mobile stations to be dynamically grouped into multicast groupings to reduce system overhead resource requirements.
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Patent Agency Ranking
公开(公告)号：US20190288893A1
公开(公告)日：2019-09-19
申请号：US16433273
申请日：2019-06-06
Applicant: Apple Inc.
Inventor： Jianglei Ma , Ming Jia , Wen Tong , Peiying Zhu , Hang Zhang , Hua Xu , Dongsheng Yu
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).
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公开(公告)号：US10397960B2
公开(公告)日：2019-08-27
申请号：US15664431
申请日：2017-07-31
Applicant: Apple Inc.
Inventor： Jianglei Ma , Hua Xu , Ming Jia , Sarah Boumendil , Evelyne Le Strat , Hang Zhang , Peiying Zhu , Wen Tong
Abstract: Physical layer structures and access schemes for use in such networks are described and in particular initial access channel (IACH) structures are proposed. A spectrum efficient downlink (DL) IACH design supports different types of User Equipment (UE) capabilities and different system bandwidths. An IACH includes the synchronization channel (SCH) and broadcast-control channel (BCH). A non-uniform SCH for all system bandwidths is provided, as well as scalable bandwidth BCH depending on system bandwidth. An initial access procedure is provided, as well as an access procedure.
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公开(公告)号：US10374856B2
公开(公告)日：2019-08-06
申请号：US15674785
申请日：2017-08-11
Applicant: APPLE INC.
Inventor： Jianglei Ma , Ming Jia , Wen Tong , Peiying Zhu , Claude Royer
Abstract: Pilot, preamble and midamble patterns are provided that are particularly suited for four transmit antenna OFDM systems. Pilots are inserted in a scattered manner for each of the four antennas, either uncoded, space-time coded in pairs, space-time frequency coded in pairs, or space-time-frequency coded.
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公开(公告)号：US10349229B2
公开(公告)日：2019-07-09
申请号：US15730111
申请日：2017-10-11
Applicant: Apple Inc.
Inventor： Jianglei Ma , Aaron Callard , Ming Jia , Wen Tong , Peiying Zhu , Hang Zhang
Abstract: Systems and methods are disclosed herein for an enhanced Multimedia Broadcast Multicast Service (MBMS) in a wireless communications network. In one embodiment, a number of base stations in a MBMS zone, or broadcast region, accommodate both Spatial Multiplexing (SM) enabled user elements and non-SM enabled user elements. In another embodiment, a number of base stations form a MBMS zone, or broadcast region, where the MBMS zone is sub-divided into an SM zone and a non-SM zone. In another embodiment, the wireless communications network includes multiple MBMS zones. For each MBMS zone, base stations serving the MBMS zone transmit an MBMS zone identifier (ID) for the MBMS zone. The MBMS zone ID may be used by a user element for decoding and/or to determine when to perform a handoff from one MBMS zone to another.
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公开(公告)号：US10348542B2
公开(公告)日：2019-07-09
申请号：US16255702
申请日：2019-01-23
Applicant: Apple Inc.
Inventor： Jianglei Ma , Ming Jia , Wen Tong , Peiying Zhu , Hang Zhang , Hua Xu , Dongsheng Yu
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).
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