公开(公告)号：US07439907B2

公开(公告)日：2008-10-21

申请号：US11561758

申请日：2006-11-20

Applicant: Chi-Shin Wang ,  David Wang ,  Wentao Zhang ,  Jun Mo ,  Lei Dong

Inventor： Chi-Shin Wang ,  David Wang ,  Wentao Zhang ,  Jun Mo ,  Lei Dong

IPC: G01S3/14

CPC classification number: G01S19/49 ,  G01S19/40

Abstract: The present invention provides methods and systems that enable a mobile navigation receiver to accurately determine its trajectory with non-current ephemeris in stand-alone mode. In an embodiment, the receiver computes the position for the same location using non-current ephemeris and current ephemeris at different time instances. The receiver then determines a position correction by finding the difference between these two computed positions, and applies this correction to the trajectory generated with non-current ephemeris to obtain a more accurate trajectory. In another embodiment, the receiver computes an initial position of the receiver using non-current ephemeris and finds the difference between the computed initial position and an accurate approximation of the initial position. The receiver then shifts the subsequent receiver trajectory computed using non-current ephemeris by the difference to obtain a more accurate trajectory.

Abstract translation: 本发明提供使移动导航接收机能够以独立模式的非当前星历精确地确定其轨迹的方法和系统。 在一个实施例中，接收机使用不同时间的非当前星历和当前星历表计算相同位置的位置。 然后，接收机通过找到这两个计算位置之间的差异来确定位置校正，并将该校正应用于由非当前星历产生的轨迹，以获得更准确的轨迹。 在另一个实施例中，接收机使用非当前星历表计算接收机的初始位置，并且找出所计算的初始位置与初始位置的精确近似之间的差。 然后，接收器将使用非当前星历计算的后续接收器轨迹移动该差，以获得更准确的轨迹。

公开(公告)号：US20080150797A1

公开(公告)日：2008-06-26

申请号：US11615431

申请日：2006-12-22

Applicant: Zhike Jia ,  Shridhara A. Kurethaya ,  Chi-Shin Wang

Inventor： Zhike Jia ,  Shridhara A. Kurethaya ,  Chi-Shin Wang

IPC: G01S1/04 ,  G01S5/14

CPC classification number: G01S19/34 ,  G01S19/24

Abstract: The present invention provides systems and methods for navigational signal tracking in low power mode to conserve the power of handheld navigation receivers. In an embodiment, the receiver cycles between sleep and wakeup states. During the sleep state, most of the components of the receiver are powered off to conserve power, and during the wakeup state, the receiver tracks navigational signals. In an embodiment, the duty cycle of the sleep/wakeup states depends on the receiver dynamic state, e.g., whether the receiver is accelerating. In another embodiment, during the wakeup state, the receiver selects a tracking mode based on the signal strength. Under weak signal conditions, a tracking mode using a long integration to track the satellite signal is disclosed. In one embodiment, a tracking mode tracks the navigation signal by performing data aided integration using known or predicted data bits, such as the TLM and HOW words.

Abstract translation: 本发明提供了用于低功率模式的导航信号跟踪的系统和方法，以节省手持式导航接收机的功率。 在一个实施例中，接收器在睡眠和唤醒状态之间循环。 在睡眠状态期间，接收机的大多数组件被断电以节省功率，并且在唤醒状态期间，接收机跟踪导航信号。 在一个实施例中，睡眠/唤醒状态的占空比取决于接收机的动态状态，例如接收机是否正在加速。 在另一个实施例中，在唤醒状态期间，接收机基于信号强度来选择跟踪模式。 在弱信号条件下，公开了使用长积分跟踪卫星信号的跟踪模式。 在一个实施例中，跟踪模式通过使用已知或预测的数据位（诸如TLM和HOW字）执行数据辅助积分来跟踪导航信号。

公开(公告)号：US20080117103A1

公开(公告)日：2008-05-22

申请号：US11561749

申请日：2006-11-20

Applicant: Chi-Shin Wang ,  David Wang ,  Zongde Qiu

Inventor： Chi-Shin Wang ,  David Wang ,  Zongde Qiu

IPC: G01S5/14 ,  G01S1/00

CPC classification number: G01S19/34 ,  G01S19/258

Abstract: The present invention provides methods and systems for keeping the ephemeris in a navigational receiver current to achieve fast TTFF without the need for connecting to an aiding network or remote server. In an embodiment, the receiver keeps the ephemeris current by downloading the ephemeris in the background. In the preferred embodiment, the receiver uses a background sleep/wake up process to download current ephemeris with minimal power drain. In this embodiment, the receiver alternates between a sleep mode and a wake up mode. During the wake up mode, the receiver attempts to download current ephemeris. The receiver then goes back to the sleep mode until the next wake up to conserve power. The receiver may wake up from the sleep mode to download the ephemeris when the stored ephemeris is no longer current or the ephemeris broadcasted from a satellite has been updated or based on receiver usage patterns.

Abstract translation: 本发明提供了用于将星历保持在导航接收机当中以在不需要连接到辅助网络或远程服务器的情况下实现快速TTFF的方法和系统。 在一个实施例中，接收器通过在背景中下载星历来保持星历当前的状态。 在优选实施例中，接收机使用背景睡眠/唤醒过程以最小的功率耗散来下载当前星历。 在该实施例中，接收器在睡眠模式和唤醒模式之间交替显示。 在唤醒模式下，接收端尝试下载当前星历。 接收器然后回到睡眠模式，直到下一次唤醒以节省电量。 当存储的星历不再是当前的或者从卫星广播的星历表已被更新或基于接收机使用模式时，接收机可以从休眠模式唤醒以下载星历。

公开(公告)号：US20070248152A1

公开(公告)日：2007-10-25

申请号：US11379451

申请日：2006-04-20

Applicant: Chi-Shin Wang ,  Yue Chen ,  Zhike Jia

Inventor： Chi-Shin Wang ,  Yue Chen ,  Zhike Jia

IPC: H04B1/00

CPC classification number: G01S19/24

Abstract: Fast Fourier Transform (FFT) based Phase Lock Loops (PLLs) are provided for use in navigational signal receivers. In an embodiment, a navigation receiver correlates a received navigational signal with a locally generated signal into correlation samples, e.g., one-millisecond correlation samples. The navigation receiver includes a FFT based PLL that corrects phase shifts in the correlation samples due to the Doppler frequency by considering both the Doppler frequency and its rate of change, which are obtained from a FFT computation with interpolation. The phase corrected correlation samples are then integrated over a length of a navigation data bit, e.g., 20 milliseconds, to determine the sign of the data bit of the received signal. In another embodiment, a soft decision feedback technique involving integration extending over the present data bit and several prior data bits is used to determine the sign of a present data bit of the received signal.

Abstract translation: 基于快速傅里叶变换（FFT）的锁相环（PLL）被提供用于导航信号接收机。 在一个实施例中，导航接收器将接收到的导航信号与本地生成的信号相关联成相关样本，例如，一毫秒相关样本。 导航接收机包括基于FFT的PLL，其通过考虑从具有插值的FFT计算获得的多普勒频率及其变化率来校正由于多普勒频率引起的相关样本中的相移。 然后将相位校正的相关样本在导航数据位的长度（例如20毫秒）上积分，以确定接收信号的数据位的符号。 在另一个实施例中，使用涉及在当前数据位和若干先前数据位上延伸的积分的软判决反馈技术来确定接收信号的当前数据位的符号。

公开(公告)号：US07180446B2

公开(公告)日：2007-02-20

申请号：US11179353

申请日：2005-07-12

Applicant: Chi-Shin Wang ,  Zhike Jia ,  Hansheng Wang

Inventor： Chi-Shin Wang ,  Zhike Jia ,  Hansheng Wang

IPC: G01S5/14

CPC classification number: G01S19/30

Abstract: A method and device to acquire navigational satellite signals combines non-coherent and coherent integrations and can efficiently acquire both strong and weak signals. Successive steps eliminate lower powered and less likely combinations of code offsets and carrier frequencies or dwells of a given satellite signal. Only remaining dwells then are correlated and integrated over larger time duration to obtain the most probable dwell or dwells, which results in reduced computational load. The selection of most likely dwells is based on Parseval's theorem on equivalence of power in time and frequency domains. An optimal estimator algorithm efficiently estimates the probable navigation data bits embedded in the received signal. In case of an ambiguity due to several possible dwells, the steps are repeated with a new set of signal samples.

Abstract translation: 一种获取导航卫星信号的方法和装置组合了非相干和相干的整合，可以有效地获得强信号和弱信号。 相继的步骤消除了给定卫星信号的代码偏移和载波频率或驻留的较低功率和不太可能的组合。 然后，只有剩余的住宅在较大的持续时间内相关并整合，以获得最可能的停留或停留，这导致减少的计算负荷。 最可能的住宅选择是基于时间和频域功率等效的Parseval定理。 最优估计算法有效地估计嵌入在接收信号中的可能的导航数据位。 在由于几个可能的住宅而引起歧义的情况下，用新的一组信号样本重复这些步骤。

公开(公告)号：US20060251173A1

公开(公告)日：2006-11-09

申请号：US11123861

申请日：2005-05-06

Applicant: Hansheng Wang ,  Chi-Shin Wang

Inventor： Hansheng Wang ,  Chi-Shin Wang

IPC: H04N11/04

CPC classification number: G01S19/37 ,  G01S19/235

Abstract: The present invention provides a new baseband integrated circuit (IC) architecture for direct sequence spread spectrum (DSSS) communication receivers. The baseband IC has a single set of baseband correlators serving all channels in succession. No complex parallel channel hardware is required. A single on-chip code Numerically Controlled Oscillator (NCO) drives a pseudorandom number (PN) sequence generator, generates all code sampling frequencies, and is capable of self-correct through feedback from an off-chip processor. A carrier NCO generates corrected local frequencies. These on-chip NCOs generate all the necessary clocks. This architecture advantageously reduces the total hardware necessary for the receiver and the baseband IC thus can be realized with a minimal number of gate count. The invention can accommodate any number of channels in a navigational system such as the Global Positioning System (GPS), GLONASS, WAAS, LAAS, etc. The number of channels can be increased by increasing the circuit clock speed.

Abstract translation: 本发明提供了一种用于直接序列扩频（DSSS）通信接收机的新的基带集成电路（IC）架构。 基带IC具有一组基带相关器，连续地为所有通道服务。 不需要复杂的并行通道硬件。 单个片上代码数控振荡器（NCO）驱动伪随机数（PN）序列发生器，产生所有代码采样频率，并且能够通过来自片外处理器的反馈进行自校正。 载波NCO产生校正的本地频率。 这些片上NCO产生所有必要的时钟。 该架构有利地减少了接收机和基带IC所需的总硬件，因此可以以最小数量的门数实现。 本发明可以容纳诸如全球定位系统（GPS），GLONASS，WAAS，LAAS等导航系统中的任何数量的信道。可以通过增加电路时钟速度来增加信道数量。