-
公开(公告)号:US20150103938A1
公开(公告)日:2015-04-16
申请号:US14551053
申请日:2014-11-23
Applicant: Apple Inc.
Inventor: Wen Tong , Hosein Nikopourdeilami, IV , Amir Keyvam Khandani , Hua Xu , Ming Jia , Peiying Zhu , Dong-Sheng Yu
IPC: H04B7/04
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 S1 for each codeword c1 of the codebook C. Each codeword subset S1 defines L codewords cj, which are selected from all the codewords ci in the codebook C. The codewords cj in a codeword subset S1 are the L codewords in the entire codebook that best correlate with the corresponding codeword ci.
Abstract translation: 码本C被提供在MIMO发射机以及MIMO接收机中。 码本C将包括M个码字ci,其中i是每个码字ci的唯一码字索引。 每个码字定义了应用于MIMO信号的加权因子,并且可以对应于在从MIMO发射机的各个天线发送之前应用于MIMO信号的信道矩阵或向量。 本发明为码本C的每个码字c1创建码字子集S1。每个码字子集S1定义从码本C中的所有码字ci中选择的L个码字cj。码字子集S1中的码字cj是L个码字 在整个码本中与相应的码字ci最相关。
-
公开(公告)号:US20150016394A1
公开(公告)日:2015-01-15
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
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: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.
-
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.
-
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.
-
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).
-
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.
-
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).
-
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.
-
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).
-
-
-
-
-
-
-
-
-