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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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公开(公告)号：US20190173722A1
公开(公告)日：2019-06-06
申请号：US16249672
申请日：2019-01-16
Applicant: APPLE INC.
Inventor： Jianglei Ma , Hang Zhang , Wen Tong , Ming Jia , Peiying Zhu , Mo-Han Fong
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-I and Preamble-2, which may be used in different systems, including multioutput, multi-input (MIMO) systems.
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公开(公告)号：US10284322B2
公开(公告)日：2019-05-07
申请号：US16031047
申请日：2018-07-10
Applicant: Apple Inc.
Inventor： Jianglei Ma , Ming Jia , Wen Tong , Peiying Zhu , Hua Xu , Hang Zhang , Mo-Han Fong
IPC: H04L5/00 , H04B1/707 , H04L27/26 , H04W72/04 , H04B7/0404 , H04J13/00 , H04L25/02 , H04B7/06 , H04J13/16 , H04L25/03
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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Patent Agency Ranking
公开(公告)号：US10278176B2
公开(公告)日：2019-04-30
申请号：US15723310
申请日：2017-10-03
Applicant: Apple Inc.
Inventor： Sophie Vrzic , Jun Yuan , Mo-Han Fong , Robert Novak , Dong-Sheng Yu , Jianglei Ma
IPC: H04W72/04 , H04W74/00 , H04W74/08 , H04L5/00 , H04L27/26 , H04J11/00 , H04W84/12 , H04W88/08 , H04W88/12
Abstract: A method and system are provided having an uplink control structure and a pilot signal having minimal signal overhead for providing channel estimation and data demodulation in a wireless communication network. The uplink control structures enable mobile terminals to communicate with corresponding base stations to perform various functions including obtaining initial system access, submitting a bandwidth request, triggering a continuation of negotiated service, or providing a proposed allocation re-configuration header. A dedicated random access channel is provided to communicatively couple the base station and the mobile terminal so that the mobile terminal can select a random access signaling identification. A resource request is received at the base station to uplink resource information from the mobile terminal and an initial access information request is received from the mobile terminal to configure the base station connection. Pilot signals with varying density configurations are provided to include low density symbol patterns for multiple contiguous resource blocks and high density symbol patterns for single resource blocks.
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公开(公告)号：US10200226B2
公开(公告)日：2019-02-05
申请号：US16110205
申请日：2018-08-23
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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公开(公告)号：US10110285B2
公开(公告)日：2018-10-23
申请号：US15691877
申请日：2017-08-31
Applicant: Apple Inc.
Inventor： Jianglei Ma , Ming Jia , Hua Xu , Wen Tong , Peiying Zhu , Moussa Abdi
IPC: H04W4/00 , H04B7/0452 , H04L5/00 , H04W72/04 , H04L27/26 , H04J13/18 , H04B7/0413 , H04W88/08 , H04L25/02 , H04J13/16 , H04L1/06
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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公开(公告)号：US10091693B2
公开(公告)日：2018-10-02
申请号：US14546732
申请日：2014-11-18
Applicant: APPLE INC.
Inventor： Jianglei Ma , Peiying Zhu , Wen Tong , Hang Zhang , Mo-Han Fong
Abstract: The present invention facilitates handoffs for a mobile terminal in a wireless access network that is capable of supporting different types of handoffs. The different handoff types may include soft handoffs and fast base station switching (FBSS). In operation, context information associated with supporting wireless communications between the wireless access network and the mobile terminal are determined. Based on whether the context information is shared between base stations involved in the handoff or transferred from one base station to another of the base stations involved in the handoff, a particular handoff type is selected from the different handoff types that are available. Selecting the specific type of handoff to use may also be based on the level of context information that is available, the actual content of the context information, application preferences, channel conditions, base station or mobile terminal capabilities, or any combination thereof.
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20.发明申请公开(公告)号：US20180270725A1
公开(公告)日：2018-09-20
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 , H04L27/26 , H04B7/0413
CPC classification number: H04W36/08 , H04B7/022 , H04B7/04 , H04B7/0413 , H04B7/0667 , H04B7/0697 , H04J11/0069 , H04L5/0023 , H04L5/0037 , H04L5/0048 , H04L7/0008 , H04L27/2602 , H04L27/2607 , H04L27/2613 , H04L27/2627 , H04L27/2628 , H04L27/2663 , H04L27/2665 , H04L27/2672 , H04L27/2675
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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