公开(公告)号：US09042463B2

公开(公告)日：2015-05-26

申请号：US13351071

申请日：2012-01-16

Applicant: Mingrui Zhu ,  Arun Kedambadi ,  Seung Chul Hong ,  Anand Anandakumar

Inventor： Mingrui Zhu ,  Arun Kedambadi ,  Seung Chul Hong ,  Anand Anandakumar

IPC: H04K1/10 ,  H04L27/28 ,  H04L25/02 ,  H04L27/26

CPC classification number: H04L27/2605 ,  H04L25/0216 ,  H04L25/0222 ,  H04L25/0226 ,  H04L27/2607 ,  H04L27/2647 ,  H04L27/2655

Abstract: A method and system for combining a guard interval and a corresponding portion of a received symbol, whereby when receiving a signal that contains the symbol with a guard interval corresponding to the symbol, a portion of the guard interval that is free from inter-symbol interference may be extracted, and the extracted portion of the guard interval may be combined with the corresponding portion of the symbol. The extracting and combining may be done after a determining, based on a delay profile provided by the received signal, that a delay spread is smaller than a predetermined channel delay. The delay spread may be determined by filtering an instantaneous delay spread associated with the received signal. The filtering may be performed using a 1-tap infinite impulse response low-pass filter. The low-pass filter may include a time constant that is the inverse of a maximum Doppler frequency shift.

Abstract translation: 一种用于组合保护间隔和接收到的符号的对应部分的方法和系统，由此当接收到包含具有与该符号对应的保护间隔的符号的信号时，保护间隔的一部分没有符号间干扰 可以提取保护间隔的提取部分与符号的对应部分组合。 在基于由接收信号提供的延迟分布确定延迟扩展小于预定信道延迟之后，可以进行提取和组合。 可以通过对与接收信号相关联的瞬时延迟扩展进行滤波来确定延迟扩展。 可以使用1抽头无限脉冲响应低通滤波器来执行滤波。 低通滤波器可以包括与最大多普勒频移相反的时间常数。

公开(公告)号：US08912955B2

公开(公告)日：2014-12-16

申请号：US13098314

申请日：2011-04-29

Applicant: Curtis Ling ,  Anand Anandakumar

Inventor： Curtis Ling ,  Anand Anandakumar

IPC: G01S19/34 ,  G01S19/23 ,  G01S19/05 ,  G01S19/25 ,  G01S19/31

CPC classification number: G01S19/05 ,  G01S19/256 ,  G01S19/31 ,  G01S19/34

Abstract: Systems and methods for extracting synchronization information from ambient signals, such as broadcast television signals, and using the synchronization information as a reference for correcting the local time base so that a GNSS positioning receiver system maintains relative time base accuracy with respect to a GNSS time.

Abstract translation: 从诸如广播电视信号的环境信号中提取同步信息的系统和方法，以及使用同步信息作为校正本地时基的参考，以使得GNSS定位接收机系统相对于GNSS时间维持相对的时基精度。

公开(公告)号：US08909819B2

公开(公告)日：2014-12-09

申请号：US13674008

申请日：2012-11-10

Applicant: Anand Anandakumar ,  Sheng Ye ,  Curtis Ling

Inventor： Anand Anandakumar ,  Sheng Ye ,  Curtis Ling

IPC: G06F3/00 ,  H03K9/00 ,  H04N21/443 ,  H04N21/438 ,  H04N5/44 ,  H04N21/426 ,  H04N5/50

CPC classification number: H04N21/4263 ,  H04N5/44 ,  H04N5/50 ,  H04N21/4383 ,  H04N21/4436 ,  H04N21/4622 ,  H04N21/6143

Abstract: Methods and systems for multi-path video and network channels may comprise a communication device comprising a wideband path (WB) and a narrowband path (NB), wherein the WB may be operable to receive a plurality of channels and the NB may be operable to receive a single channel. Video channels and a network channel may be received in the WB when the device is operating in a first stage. Video channels and a network channel may be received in the WB and the network channel may also be received in the NB when the device is operating in a second stage. The network channel may be received in the NB when the device is operating in a third stage. The reception of the network channel from both the WB and the NB may enable a continuous reception of the network channel in a transition between the first and third stages.

Abstract translation: 用于多路径视频和网络信道的方法和系统可以包括包括宽带路径（WB）和窄带路径（NB）的通信设备，其中，所述WB可以可操作以接收多个信道，并且所述NB可操作为 接收单个频道。 当设备在第一阶段中操作时，可以在WB中接收视频通道和网络通道。 在WB中可以接收视频信道和网络信道，并且当设备在第二阶段中操作时，也可以在NB中接收网络信道。 当设备在第三阶段中操作时，可以在NB中接收网络信道。 来自WB和NB的网络信道的接收可以使得能够在第一和第三级之间的转换中连续接收网络信道。

公开(公告)号：US20130107910A1

公开(公告)日：2013-05-02

申请号：US13413916

申请日：2012-03-07

Applicant: Maxime Leclercq ,  Ioannis Spyropoulos ,  Nishant Kumar ,  Anand Anandakumar

Inventor： Maxime Leclercq ,  Ioannis Spyropoulos ,  Nishant Kumar ,  Anand Anandakumar

IPC: H04B1/7073

CPC classification number: G01S19/46 ,  H04B7/1853 ,  H04B7/18547 ,  H04W64/006

Abstract: Methods and systems for repurposing of a global navigation satellite system receiver for receiving low-earth orbit (LEO) communication satellite timing signals may comprise receiving medium Earth orbit (MEO) satellite signals and/or LEO signals in a receiver of the communication device. A radio frequency (RF) path may be configured to down-convert either of the signals, and a position of the communication device may be calculated utilizing the down-converted signals. The signals may be down-converted utilizing a local oscillator signal generated by a phase locked loop (PLL), which may be delta-sigma modulated via a fractional-N divider. A clock signal may be communicated to the PLL utilizing a temperature-compensated crystal oscillator. The signals may be down-converted to an intermediate frequency or down-converted directly to baseband frequencies. The signals may be processed utilizing surface acoustic wave (SAW) filters. In-phase and quadrature signals may be processed in the RF path utilizing a two-stage polyphase filter.

Abstract translation: 用于重新利用用于接收低地球轨道（LEO）通信卫星定时信号的全球导航卫星系统接收机的方法和系统可以包括在通信设备的接收机中接收介质地球轨道（MEO）卫星信号和/或LEO信号。 射频（RF）路径可以被配置为下变频信号中的任一个，并且可以利用下变频信号来计算通信设备的位置。 信号可以利用由锁相环（PLL）产生的本地振荡器信号进行下变频，锁相环（PLL）可经由分数N分频器进行Δ-Σ调制。 可以使用温度补偿晶体振荡器将时钟信号传送到PLL。 信号可以被下变频到中频或者直接下变频到基带频率。 可以使用表面声波（SAW）滤波器来处理信号。 可以使用两级多相滤波器在RF路径中处理同相和正交信号。

公开(公告)号：US20120183107A1

公开(公告)日：2012-07-19

申请号：US13351071

申请日：2012-01-16

Applicant: Mingrui Zhu ,  Arun Kedambadi ,  Seung Chul Hong ,  Anand Anandakumar

Inventor： Mingrui Zhu ,  Arun Kedambadi ,  Seung Chul Hong ,  Anand Anandakumar

IPC: H04B15/00

CPC classification number: H04L27/2605 ,  H04L25/0216 ,  H04L25/0222 ,  H04L25/0226 ,  H04L27/2607 ,  H04L27/2647 ,  H04L27/2655

Abstract: A method and system for combining a guard interval and a corresponding portion of a received symbol, whereby when receiving a signal that contains the symbol with a guard interval corresponding to the symbol, a portion of the guard interval that is free from inter-symbol interference may be extracted, and the extracted portion of the guard interval may be combined with the corresponding portion of the symbol. The extracting and combining may be done after a determining, based on a delay profile provided by the received signal, that a delay spread is smaller than a predetermined channel delay. The delay spread may be determined by filtering an instantaneous delay spread associated with the received signal. The filtering may be performed using a 1-tap infinite impulse response low-pass filter. The low-pass filter may include a time constant that is the inverse of a maximum Doppler frequency shift.

Abstract translation: 一种用于组合保护间隔和接收到的符号的对应部分的方法和系统，由此当接收到包含具有与该符号对应的保护间隔的符号的信号时，保护间隔的一部分没有符号间干扰 可以提取保护间隔的提取部分与符号的对应部分组合。 在基于由接收信号提供的延迟分布确定延迟扩展小于预定信道延迟之后，可以进行提取和组合。 可以通过对与接收信号相关联的瞬时延迟扩展进行滤波来确定延迟扩展。 可以使用1抽头无限脉冲响应低通滤波器来执行滤波。 低通滤波器可以包括与最大多普勒频移相反的时间常数。

公开(公告)号：US20130332968A1

公开(公告)日：2013-12-12

申请号：US13916130

申请日：2013-06-12

Applicant: Anand Anandakumar ,  Ioannis Spyropoulos ,  Meetul Parikh

Inventor： Anand Anandakumar ,  Ioannis Spyropoulos ,  Meetul Parikh

IPC: H04N21/647

CPC classification number: H04N21/64738 ,  H04N21/438 ,  H04N21/44209 ,  H04N21/6143

Abstract: A signal receiver may be configured to determine when signal generation changes affecting signals being received by the signal receiver may cause performance related changes; and to modify its (the signal receiver) configuration to handle the performance related changes. In this regard, the modifying of configuration may comprise determining characteristics of performance related changes, and controlling operations of the signal receiver based on the determined characteristics of the performance related changes. The performance related changes may comprise amplitude glitches, phase glitches, and/or bit or packet errors. The signal generation changes may comprise channel-to-frequency re-assignment. Controlling operations of the signal receiver based on determined characteristics of the performance related changes may comprise adjusting such parameters as amplification gain and/or tracking loop bandwidth, and/or determining whether (or not) to ignore bit/packet errors—i.e. not reacquire (e.g., based on determination that tracking loops used in the signal receiver remain locked).

Abstract translation: 信号接收机可以被配置为确定何时影响由信号接收器接收的信号的信号产生改变可能导致性能相关的变化; 并修改其（信号接收器）配置以处理性能相关的更改。 在这方面，配置的修改可以包括确定性能相关变化的特性，以及基于所确定的性能相关变化的特性来控制信号接收机的操作。 性能相关的变化可能包括幅度毛刺，相位毛刺和/或位或分组错误。 信号产生改变可以包括频率 - 频率重新分配。 基于性能相关变化的确定特性来控制信号接收机的操作可以包括调整诸如放大增益和/或跟踪环路带宽之类的参数，和/或确定是否（或不））忽略比特/分组错误 - 即， 不重新获取（例如，基于在信号接收器中使用的跟踪环路保持锁定的确定）。

公开(公告)号：US08548075B2

公开(公告)日：2013-10-01

申请号：US12947667

申请日：2010-11-16

Applicant: Seung-Chul Hong ,  Anand Anandakumar ,  Curtis Ling

Inventor： Seung-Chul Hong ,  Anand Anandakumar ,  Curtis Ling

IPC: H04K1/10

CPC classification number: H04L1/0023 ,  H04L5/0007 ,  H04L7/0016 ,  H04L25/0216 ,  H04L27/265 ,  H04L27/2665 ,  H04L27/2671 ,  H04L27/2695

Abstract: Systems and methods for adjusting timing in a communication system, such as an OFDM system are described. In one implementation an error signal is generated to adjust the timing of a variable rate interpolator so as to adjust FFT timing. The error signal may be based on detection of significant peaks in an estimate of the impulse response of the channel, with the peak locations being tracked over subsequent symbols and the system timing adjusted in response to changes in the peaks.