公开(公告)号：US20100278220A1

公开(公告)日：2010-11-04

申请号：US12747505

申请日：2008-12-12

申请人： Lawrence R. Weill

发明人： Lawrence R. Weill

IPC分类号： H04B1/707

CPC分类号： H04B1/709 ,  G01S19/14 ,  G01S19/24 ,  G01S19/243 ,  G01S19/39

摘要： Sub-microsecond time transfer in a GPS/GNSS receiver using a weak GPS/GNSS signal is provided. The digitized complex baseband signal and the generated PN code are cross-correlated for each code period so as to output a complex correlation value at each code epoch of the generated PN code, where a sequence of the output correlation values form a data stream representing the navigation message. Bit synchronization generates bit sync pulses at bit boundaries. The location of a target segment having a known sequence at a known bit location in the navigation message is detected by searching through a plurality of sub-frames and accumulating search results for the plurality of subframes. Transmission time of the target segment is determined from the detected location of the target segment, with a certain time ambiguity. Accurate local time is determined by solving the time ambiguity using approximate time obtained from an external source.

摘要翻译： 提供了使用弱GPS / GNSS信号的GPS / GNSS接收机中的亚微秒时间传输。 数字化复基带信号和所生成的PN码对于每个码周期是交叉相关的，以便在所生成的PN码的每个码周期输出复相关值，其中输出相关值的序列形成表示 导航信息。 位同步在位边界生成位同步脉冲。 通过搜索多个子帧并累积多个子帧的搜索结果来检测在导航消息中的已知比特位置处具有已知序列的目标段的位置。 从目标段的检测位置确定目标段的传输时间，具有一定的时间模糊度。 通过使用从外部源获得的近似时间求解时间歧义来确定准确的本地时间。

公开(公告)号：US20160179748A1

公开(公告)日：2016-06-23

申请号：US14971923

申请日：2015-12-16

申请人： Lawrence R. Weill

发明人： Lawrence R. Weill

IPC分类号： G06F17/13

CPC分类号： G06F17/13 ,  G01S5/0215 ,  G01S5/0221

摘要： The invention described herein is directed to a method and apparatus for estimating an onset time t0 of a noisy waveform by producing a time t1 that a magnitude of the noisy waveform crosses a positive threshold T which is as small as possible while keeping the probability of false crossings due to noise at an acceptable level. The estimate of the onset time t0 uses an initial portion of a noisy waveform magnitude leading edge to avoid errors due to later-occurring multipath components. The invention also produces a derivative of the noisy waveform magnitude at time t1, which is used to normalize against errors due to variations to power level without having to use any portion of the noisy waveform beyond time t1. The waveform to which the invention applies can be a received signal, the cross-correlation function derived from a received signal, or another waveform where onset time needs to be estimated.

摘要翻译： 本文描述的本发明涉及一种用于通过产生时间t1来估计噪声波形的起始时间t0的方法和装置，其中噪声波形的幅度跨越尽可能小的正阈值T，同时保持假概率 由于噪音在可接受的水平上过境。 开始时间t0的估计使用噪声波形幅度前沿的初始部分，以避免由于稍后发生的多径分量引起的误差。 本发明还在时间t1产生噪声波形幅度的导数，其用于对由于功率电平变化引起的误差进行归一化，而不必使用超过时间t1的噪声波形的任何部分。 本发明应用的波形可以是接收信号，从接收信号导出的互相关函数，或需要估计起始时间的另一个波形。

公开(公告)号：US08391340B2

公开(公告)日：2013-03-05

申请号：US12677787

申请日：2008-09-15

申请人： Lawrence R. Weill

发明人： Lawrence R. Weill

IPC分类号： H04B1/00

CPC分类号： G01S19/37

摘要： A low-cost GPS/GNSS receiver receives a satellite signal at an RF frequency (fRF). The GPS/GNSS receiver includes a front end section for receiving the satellite signal and generating a digital complex signal having a first bandwidth, the received satellite signal being converted into a complex signal before digitizing, a signal capturing section for searching for and acquiring the satellite signal, the signal capturing section including a capture memory, a baseband processor for tracking the acquired satellite signal, and a signal splitter coupled to the front end section. The signal splitter splits the digital complex signal into two bandwidths, by generating a narrowband digital complex signal having a second bandwidth substantially smaller than the first bandwidth. The signal splitter provides the narrowband digital signal to the capture memory and the wider first bandwidth digital complex signal to the baseband processor.

摘要翻译： 低成本GPS / GNSS接收机以RF频率（fRF）接收卫星信号。 GPS / GNSS接收机包括用于接收卫星信号并产生具有第一带宽的数字复合信号的前端部分，所接收的卫星信号在数字化之前被转换成复信号，用于搜索和获取卫星的信号捕获部分 信号，所述信号捕获部分包括捕获存储器，用于跟踪获取的卫星信号的基带处理器，以及耦合到所述前端部分的信号分离器。 信号分路器通过产生具有基本上小于第一带宽的第二带宽的窄带数字复信号，将数字复信号分离成两个带宽。 信号分离器将窄带数字信号提供给捕获存储器，并将较宽的第一带宽数字复合信号提供给基带处理器。

公开(公告)号：US07646830B1

公开(公告)日：2010-01-12

申请号：US11211876

申请日：2005-08-26

申请人： Lawrence R. Weill

发明人： Lawrence R. Weill

IPC分类号： H04L27/06

CPC分类号： G01S19/22 ,  G01S7/292

摘要： In ranging systems such as GPS, radar, and the like, accuracy of the ranging information recovered depends on the phase linearity of the ranging receiver, generally implemented as a superheterodyne radio. Superheterodyne radios use bandpass filters in their Intermediate Frequency (IF) amplifiers to accomplish suppression of adjacent channel signal interference. Depending on the ratio of IF center-frequency to signal-bandwidth, such filters evidence phase non-linearity affecting the signal group delay response. This generally manifests in coupling of the in-phase and quadrature detected signals during signal modulation changes in state. If this effect is ignored, reduced accuracy in the recovery of ranging information can be expected. One solution is to incorporate in the ranging receiver a phase non-linearity compensation structure, but this has an adverse economic impact. On study, it has been determined that real-time Maximum Likelihood estimates of signal parameters in a multipath environment is both tractable and efficacious. The subject of this invention is means to obtain Maximum Likelihood estimates of the amplitude, carrier phase, and delay parameters of the direct and secondary path signals arising in a multipath environment when the receiver signal modulation is complex-valued, an appropriate signal model when phase non-linearity is operating. An algorithmic solution to the problem of ranging receiver induced phase non-linearity is a preferred solution, since there is little to no economic impact.

摘要翻译： 在诸如GPS，雷达等的测距系统中，恢复的测距信息的精度取决于测距接收机的相位线性度，通常被实现为超外差无线电。 超外差无线电在其中频（IF）放大器中使用带通滤波器来完成相邻信道信号干扰的抑制。 根据IF中心频率与信号带宽的比例，这种滤波器可以证实影响信号组延迟响应的相位非线性。 这通常表现在信号调制变化状态下的同相和正交检测信号的耦合。 如果忽略这种效果，可以预期降低测距信息恢复的准确性。 一个解决方案是在测距接收机中并入相位非线性补偿结构，但这具有不利的经济影响。 在研究中，已经确定，多径环境中的信号参数的实时最大似然估计是易于处理和有效的。 本发明的主题是当接收机信号调制是复值时，获得在多径环境中产生的直接和次级路径信号的幅度，载波相位和延迟参数的最大似然估计的手段，当相位为适当的信号模型时 非线性运行。 测距接收机诱发相位非线性问题的算法解决方案是一个优选的解决方案，因为几乎没有经济影响。

公开(公告)号：US07362265B2

公开(公告)日：2008-04-22

申请号：US11103499

申请日：2005-04-12

申请人： Lawrence R. Weill

发明人： Lawrence R. Weill

IPC分类号： G01S1/00

CPC分类号： G01S19/258 ,  G01S19/42

摘要： A base station (server) transmits assisting information to the user's receiver (rover). Signals from at least 5 satellites are used for 3-dimensional positioning. Pseudorange measurements are made in a system of equations having a minimum set of unknowns X,Y,Z, and T. (X,Y,Z) is the 3D rover position in a predefined coordinate system, and T is the time at which simultaneous measurements are made to determine pseudoranges to all satellites. The position of each satellite is a vector-valued function ƒk (T) of said time T, where fk is determined from satellite ephemeris data or its equivalent, sent to the rover over a communication link, as well as from knowledge of the approximate position of the rover.

摘要翻译： 基站（服务器）向用户的接收者（流动站）发送辅助信息。 来自至少5颗卫星的信号用于三维定位。 在具有最小未知数X，Y，Z和T​​的集合的方程组中进行伪距测量。（X，Y，Z）是预定坐标系中的3D流动站位置，T是同时 进行测量以确定所有卫星的伪距。 每个卫星的位置是所述时间T的向量值函数f（k），其中，从卫星星历数据或其等效物确定f k 流动站在通信链路上，以及从流动站的大致位置的知识。