-
公开(公告)号：US10075314B2
公开(公告)日：2018-09-11
申请号：US15891750
申请日：2018-02-08
Applicant: Apple Inc.
Inventor： Jianglei Ma , Ming Jia , Wen Tong , Peiying Zhu , Hang Zhang , Hua Xu , Dongsheng Yu
CPC classification number: H04L27/2611 , H04B7/06 , H04B7/08 , H04L5/0007 , H04L5/0023 , H04L25/0226 , H04L25/0232 , H04L27/2626 , H04L27/2647
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).
-
公开(公告)号：US10044460B2
公开(公告)日：2018-08-07
申请号：US15399028
申请日：2017-01-05
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.
-
公开(公告)号：US09900069B2
公开(公告)日：2018-02-20
申请号：US15665711
申请日：2017-08-01
Applicant: Apple Inc.
Inventor： Wen Tong , Hosein Nikopour , Amir Khandani , Hua Xu , Ming Jia , Peiying Zhu , Dong-sheng Yu
IPC: H04B7/04 , H04B7/0456 , H04L29/06 , H04B7/0417 , H04B7/06
CPC classification number: H04B7/0478 , H04B7/0417 , H04B7/0456 , H04B7/0634 , H04B7/0639 , H04L69/04 , H04L69/14
Abstract: A codebook C is provided in a MIMO transmitter as well as a MIMO receiver. The codebook C will include M codewords ci, where i is a unique codeword index for each codeword ci. Each codeword defines weighting factors to apply to the MIMO signals, and may correspond to channel matrices or vectors to apply to the MIMO signals prior to transmission from the respective antennas of the MIMO transmitter. The present invention creates codeword subsets Si for each codeword ci of the codebook C. Each codeword subset Si defines L codewords cj, which are selected from all the codewords ci in the codebook C. The codewords cj in a codeword subset Si are the L codewords in the entire codebook that best correlate with the corresponding codeword ci.
-
公开(公告)号：US09838944B2
公开(公告)日：2017-12-05
申请号：US15473815
申请日：2017-03-30
Applicant: Apple Inc.
Inventor： Hang Zhang , Peiying Zhu , Wen Tong , Nimal Gamini Senarath , Derek Yu , David G. Steer
IPC: H04W4/00 , H04L12/28 , G01R31/08 , H04W40/12 , H04W28/18 , H04B7/26 , H04L12/46 , H04L29/06 , H04W16/26 , H04W28/24 , H04W72/04 , H04W76/02 , H04W84/04 , H04W84/12
CPC classification number: H04W40/12 , H04B7/2606 , H04L12/4633 , H04L47/24 , H04L47/28 , H04L69/22 , H04W16/26 , H04W28/18 , H04W28/24 , H04W40/22 , H04W72/0413 , H04W72/042 , H04W76/12 , H04W84/047 , H04W84/12
Abstract: A wireless communication access path exists between an ingress station and an egress station. A logical communication tunnel is established between the ingress and egress stations directly or through any number of intermediate relay stations to handle session flows of PDUs. As PDUs arrive, the ingress station may determine and add information bearing on an identified QoS associated with the PDU to the PDUs before they are delivered to the downstream egress station(s) or intermediate relay station(s). The information may be used by the downstream stations to schedule the PDUs for further delivery. The information may also be used by the egress station to schedule the PDUs for delivery.
-
公开(公告)号：US09832775B2
公开(公告)日：2017-11-28
申请号：US15075474
申请日：2016-03-21
Applicant: APPLE INC.
Inventor： Hang Zhang , Mo-Han Fong , Peiying Zhu , Wen Tong , Jianglei Ma
CPC classification number: H04W72/0453 , H04L5/0058 , H04L5/0091 , H04L5/0092 , H04L27/2601 , H04W28/06 , H04W72/042
Abstract: A channel descriptor management message is transmitted on a broadcast connection to a mobile terminal. The channel descriptor management message provides a format for a frame. The frame includes a resource space. The channel descriptor management message defines a plurality of channels within the resource space and allocates at least one of the channels to a plurality of users. Subsequent resource allocation messages may refer to a location within a channel rather than a location within the entire resource space.
-
Patent Agency Ranking
公开(公告)号：US09825793B2
公开(公告)日：2017-11-21
申请号：US15195083
申请日：2016-06-28
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.
-
公开(公告)号：US09813136B2
公开(公告)日：2017-11-07
申请号：US15357552
申请日：2016-11-21
Applicant: APPLE INC.
Inventor： Mahmoud Taherzadehboroujeni , Hosein Nikopour , Amir Khandani , Wen Tong , Ming Jia , Peiying Zhu , Dong-Sheng Yu , Jianglei Ma
CPC classification number: H04B7/0669 , H04B7/0413 , H04B7/06 , H04B7/0697 , H04B7/0891 , H04L1/0606 , H04L1/0625 , H04L1/0643 , H04L1/0668 , H04L5/0007 , H04L5/0023 , H04L5/0028 , H04L27/2626
Abstract: Methods and devices are provided for MIMO OFDM transmitter and receivers having odd and/even numbers of transmit antennas. Various methods for pre-coding information bits before space time coding (STC) are described for enabling transmission of information bits over all antennas. Methods of decoding received signals that have been pre-coded and STC coded are also provided by embodiments of the invention. Pilot patterns for downlink and uplink transmission between a base station and one or more wireless terminals for three transmit antenna transmitters are also provided. Variable rate codes are provided that combine various fixed rate codes in a manner that results in codes whose rates are dependent on all the various fixed rate codes that are combined.
-
公开(公告)号：US20170289816A1
公开(公告)日：2017-10-05
申请号：US15631921
申请日：2017-06-23
Applicant: Apple Inc.
Inventor： James Mark Naden , Peiying Zhu
CPC classification number: H04W16/12 , H04B7/15542 , H04B7/2606 , H04L5/0007 , H04L5/0041 , H04L5/0044 , H04L27/2627 , H04W72/04 , H04W72/0426 , H04W72/044 , H04W72/0446 , H04W72/0486 , H04W84/047
Abstract: The capacity of a cellular wireless system is increased by operation of base stations or base station sectors arranged to re-use radio resource elements that are used by neighbouring base stations or base station sectors, in conjunction with operation of relay stations, which are similarly arranged to re-use radio resource elements used by neighbouring relay stations, and where the radio resource elements re-used by the relay stations are different to those used by the base stations. The relay stations provide coverage, particularly in the areas at the boundaries between the areas of coverage of base stations that suffer from interference between signals transmitted from the respective base stations. In addition, the relay stations generally increase the average available carrier to interference ratio compared with a system in which base stations alone are deployed. The scheme for the allocation of radio resource elements ensures in particular that interference is avoided between signals transmitted from a base station and signals transmitted from a relay station in radio resource elements allocated to control data,
-
公开(公告)号：US09762300B2
公开(公告)日：2017-09-12
申请号：US14499316
申请日：2014-09-29
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
CPC classification number: H04B7/0452 , H04B7/0413 , H04J13/18 , H04J2013/165 , H04L1/0625 , H04L5/001 , H04L5/0026 , H04L5/0032 , H04L5/0048 , H04L5/005 , H04L5/0051 , H04L25/0226 , H04L25/0228 , H04L27/2613 , H04W72/04 , H04W72/044 , 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.
-
公开(公告)号：US09705720B2
公开(公告)日：2017-07-11
申请号：US15226101
申请日：2016-08-02
Applicant: Apple Inc.
Inventor： Jianglei Ma , Ming Jia , Wen Tong , Peiying Zhu , Hang Zhang , Hua Xu , Dong-Sheng Yu
CPC classification number: H04L27/2611 , H04B7/06 , H04B7/08 , H04L5/0007 , H04L5/0023 , H04L25/0226 , H04L25/0232 , H04L27/2626 , H04L27/2647
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).
-
-
-
-
-
-
-
-
-
Search Results
239
records
(took 0.023 seconds)
