公开(公告)号：US08947994B2

公开(公告)日：2015-02-03

申请号：US14251627

申请日：2014-04-13

Applicant: Apple Inc.

Inventor： Jianglei Ma ,  Wen Tong ,  Ming Jia ,  Hua Xu ,  Peiying Zhu ,  Hang Zhang

IPC: H04J9/00 ,  H04L27/26 ,  H04L5/00 ,  H04L1/00

CPC classification number: H04L27/263 ,  H04L1/0003 ,  H04L1/0009 ,  H04L5/0007 ,  H04L5/0023 ,  H04L5/0044 ,  H04L5/0096 ,  H04L27/2613 ,  H04L27/2628 ,  H04L27/2634 ,  H04L27/2646

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.

Abstract translation: 提供了使OFDM发射机能够用于传输常规OFDM或变换OFDM形式的方法和系统。 提供了一种用于在IFFT之前变换样本的编码和调制序列的技术，其使得能够使用常规OFDM或变换OFDM来发送变换的样本序列。 用于变换样本的编码和调制序列的变换函数的选择可以基于优化发射机和接收机之间的特定操作条件的变换函数。 在本发明的一些实施例中，OFDM和时变OFDM在传输帧中以时间和/或频率被复用。 在本发明的一些实施例中，提供了导频模式，其中使用OFDM发送导频，并且使用OFDM和/或经变换的OFDM发送数据。

公开(公告)号：US08842756B2

公开(公告)日：2014-09-23

申请号：US13665982

申请日：2012-11-01

Applicant: Apple Inc.

Inventor： Jianglei Ma ,  Ming Jia ,  Hua Xu ,  Wen Tong ,  Peiying Zhu ,  Dong-Sheng Yu ,  Hang Zhang

IPC: H04K1/10

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).

Abstract translation: 一种用于改善OFDM通信系统内的信道估计的方法和装置。 OFDM中的信道估计通常借助于导频符号来执行。 导频符号通常在时间和频率上间隔开。 将导频符号插入的频率和时间的集合称为导频模式。 在一些情况下，导频图案是对角线形格子，规则的或不规则的。 该方法首先在较大相干性（时间或频率）的方向内插。 使用这些测量，导频符号在更快变化方向上的密度将增加，从而改善信道估计而不增加开销。 因此，第一内插步骤的结果然后可以用于辅助尺寸较小的相干性（时间或频率）的内插。

公开(公告)号：US20140211778A1

公开(公告)日：2014-07-31

申请号：US14231595

申请日：2014-03-31

Applicant: Apple Inc.

Inventor： Ming Jia ,  Jianglei Ma ,  Peiying Zhu ,  Wen Tong ,  Hua Xu ,  Hang Zhang

IPC: H04L5/00 ,  H04B7/06 ,  H04B7/26

CPC classification number: H04L5/0058 ,  H04B7/0602 ,  H04B7/0671 ,  H04B7/2621 ,  H04J11/00 ,  H04L1/0003 ,  H04L1/0625 ,  H04L5/0007 ,  H04L5/0023 ,  H04L5/0044 ,  H04L5/0048 ,  H04L5/0091 ,  H04L27/2615 ,  H04L27/2626 ,  H04L27/2636

Abstract: The present application provides methods, devices and transmitters that mitigate increases in peak to average power ratio (PAPR) from transmission diversity in a single carrier frequency division multiple access (SC-FDMA) modulated uplink. A PAPR preserving precode matrix hopping method that utilizes cyclic shift delays is provided, as well as a sub-band based transmit diversity scheme. The present application also provides methods, devices and transmitters that relax the scheduling restrictions associated with uplink scheduling in the LTE standard.

Abstract translation: 本申请提供了在单载波频分多址（SC-FDMA）调制的上行链路中减轻来自传输分集的峰均功率比（PAPR）的增加的方法，装置和发射机。 提供了利用循环移位延迟的PAPR保留预编码矩阵跳频方法以及基于子带的发射分集方案。 本申请还提供了放宽与LTE标准中的上行链路调度相关联的调度限制的方法，设备和发射机。

公开(公告)号：US20140119471A1

公开(公告)日：2014-05-01

申请号：US13944022

申请日：2013-07-17

Applicant: Apple Inc.

Inventor： Jianglei Ma ,  Ming Jia ,  Wen Tong ,  Peiying Zhu ,  Hang Zhang ,  Hua Xu ,  Dong-Sheng Yu

IPC: H04L27/26

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).

Abstract translation: 一种用于改善OFDM通信系统内的信道估计的方法和装置。 OFDM中的信道估计通常借助于导频符号来执行。 导频符号通常在时间和频率上间隔开。 将导频符号插入的频率和时间的集合称为导频模式。 在一些情况下，导频图案是对角线形格子，规则的或不规则的。 该方法首先在较大相干性（时间或频率）的方向内插。 使用这些测量，导频符号在更快变化方向上的密度将增加，从而改善信道估计而不增加开销。 因此，第一内插步骤的结果然后可以用于辅助尺寸较小的相干性（时间或频率）的内插。