公开(公告)号：US20190028155A1

公开(公告)日：2019-01-24

申请号：US16036372

申请日：2018-07-16

Applicant: National Instruments Corporation

Inventor： Jörg Hofrichter ,  Michael Löhning ,  Eckhard Ohlmer

IPC: H04B7/0417 ,  H04B1/40 ,  H04L1/00 ,  H01Q1/24

Abstract: In a wireless transceiver station having M antennas, designate an antenna as a target reference antenna (TRA) and for each antenna m other than the TRA: define N distinct paths from antenna m to TRA through zero or more intermediate reference antennas, N is two or more, each distinct paths has a distinct associated set of one or more antenna pairs; for each antenna pair of the sets, estimate an effective forward and backward channel response by sending calibration pilots forth and back between the antenna pair and calculate a reciprocity coefficient for the antenna pair using the estimated channel responses; for each of the N distinct paths, calculate a reciprocity coefficient estimate using the reciprocity coefficients calculated for the set of antenna pairs associated with the path; and combine the N calculated reciprocity coefficient estimates to produce a final reciprocity coefficient estimate for antenna pair (m, target reference antenna).

公开(公告)号：US10218549B1

公开(公告)日：2019-02-26

申请号：US15879369

申请日：2018-01-24

Applicant: National Instruments Corporation

Inventor： Michael Löhning ,  Eckhard Ohlmer

IPC: H04L1/00 ,  H04L7/00 ,  H04L27/227 ,  H04L25/03

Abstract: A post-equalization phase tracking unit, for each signal block of a received series: computes beginning absolute phase rotation using equalized preceding pilot symbols; subdivides the block into a time sequence of groups of equalized symbols; initializes accumulated phase associated with the first-in-time group with the absolute phase rotation. For each group, the unit: computes a de-rotated version of each symbol using the previous group's accumulated phase used to blindly estimate a residual group phase; assigns the group's accumulated phase with a sum of the group's residual phase and the previous group's accumulated phase; estimates phase drift within the group by using at least the group's accumulated phase to compute a phase compensation signal. A pre-equalization phase tracking unit computes a phase of autocorrelation between identical-as-transmitted initial/terminal sequence portions; estimates a start phase using the autocorrelation phase and the previous signal block start phase; interpolates start phases to estimate phase drift.

公开(公告)号：US09692586B2

公开(公告)日：2017-06-27

申请号：US14691339

申请日：2015-04-20

Applicant: NATIONAL INSTRUMENTS CORPORATION

Inventor： Yong Rao ,  Ahsan Aziz ,  Eckhard Ohlmer ,  James W. McCoy

IPC: H04W72/04 ,  H04L5/22 ,  H04B7/26 ,  H04L1/00 ,  H04W72/12 ,  H04L5/14

CPC classification number: H04L5/22 ,  H04B7/2656 ,  H04L1/00 ,  H04L5/14 ,  H04W72/1242

Abstract: A flexible real-time scheduler for a wireless communication node, enabling the node to communicate with a remote node using dynamically variable frame structure. The scheduler continuously receives map information defining the frame structure of frames in a frame sequence. Each frame includes a plurality of slots (e.g., time slots or frequency slots). The map information specifies for each slot of each frame whether the slot is to be a transmit slot or a receive slot. The scheduler drives a transmitter to transmit during the slots assigned for transmission, and drives a receiver to receive during the slots assigned for reception. (The number of slots per frame and the size of each slot are also configurable.)

公开(公告)号：US10312978B2

公开(公告)日：2019-06-04

申请号：US16036372

申请日：2018-07-16

Applicant: National Instruments Corporation

Inventor： Jörg Hofrichter ,  Michael Löhning ,  Eckhard Ohlmer

IPC: H04W52/08 ,  H04B7/0417 ,  H01Q1/24 ,  H04L1/00 ,  H04B1/40

Abstract: In a wireless transceiver station having M antennas, designate an antenna as a target reference antenna (TRA) and for each antenna m other than the TRA: define N distinct paths from antenna m to TRA through zero or more intermediate reference antennas, N is two or more, each distinct paths has a distinct associated set of one or more antenna pairs; for each antenna pair of the sets, estimate an effective forward and backward channel response by sending calibration pilots forth and back between the antenna pair and calculate a reciprocity coefficient for the antenna pair using the estimated channel responses; for each of the N distinct paths, calculate a reciprocity coefficient estimate using the reciprocity coefficients calculated for the set of antenna pairs associated with the path; and combine the N calculated reciprocity coefficient estimates to produce a final reciprocity coefficient estimate for antenna pair (m, target reference antenna).

公开(公告)号：US10218548B1

公开(公告)日：2019-02-26

申请号：US15879318

申请日：2018-01-24

Applicant: National Instruments Corporation

Inventor： Michael Löhning ,  Eckhard Ohlmer

IPC: H04L1/00 ,  H04L7/00 ,  H04L27/227 ,  H04L25/03

Abstract: A pre-equalization phase tracking unit, for each signal block of received series: computes autocorrelation between portion of identical-as-transmitted initial and terminal sequences and computes phase of autocorrelation; estimates start phase of block processing window using autocorrelation phase and start phase of previous signal block in series; estimates phase drift within window by interpolating using estimated start phases of at least the signal block and next signal block in series; and computes phase compensation signal using estimated phase drift. A post-equalization phase tracking unit subdivides the block into time sequence of groups of equalized symbols. For each group: compute de-rotated version of each symbol using previous group's accumulated phase to blindly estimate residual group phase; assign group's accumulated phase with sum of group's residual phase and previous group's accumulated phase; estimate phase drift within group by using at least group's accumulated phase to compute phase compensation signal.

公开(公告)号：US20150305029A1

公开(公告)日：2015-10-22

申请号：US14691339

申请日：2015-04-20

Applicant: NATIONAL INSTRUMENTS CORPORATION

Inventor： Yong Rao ,  Ahsan Aziz ,  Eckhard Ohlmer ,  James W. McCoy

IPC: H04W72/04 ,  H04L5/22

CPC classification number: H04L5/22 ,  H04B7/2656 ,  H04L1/00 ,  H04L5/14 ,  H04W72/1242

Abstract: A flexible real-time scheduler for a wireless communication node, enabling the node to communicate with a remote node using dynamically variable frame structure. The scheduler continuously receives map information defining the frame structure of frames in a frame sequence. Each frame includes a plurality of slots (e.g., time slots or frequency slots). The map information specifies for each slot of each frame whether the slot is to be a transmit slot or a receive slot. The scheduler drives a transmitter to transmit during the slots assigned for transmission, and drives a receiver to receive during the slots assigned for reception. (The number of slots per frame and the size of each slot are also configurable.)

Abstract translation: 用于无线通信节点的灵活的实时调度器，使节点能够使用动态可变的帧结构与远程节点进行通信。 调度器连续地接收定义帧序列中的帧的帧结构的映射信息。 每个帧包括多个时隙（例如，时隙或频率时隙）。 映射信息为每个帧的每个时隙指定时隙是发送时隙还是接收时隙。 调度器驱动发射机在分配用于传输的时隙期间进行传输，并且在分配给接收的时隙期间驱动接收机接收接收机。 （每帧的插槽数量和每个插槽的大小也可以配置。）