摘要:
Methods for authentication or validation of the location of a putative source (ps) of a message, using time varying location determination (LD) signals that are received from J sources (J>1) of LD signals G(t;j;ps) that are spaced apart from the putative source. The putative source forms an augmented data signal that includes the original message, one or more segments g�t.sub.k(m),t.sub.k(m+1) ; j; ps!={G(t.sub.r ;j;ps).vertline.t.sub.k(m) .ltoreq.t.sub.r .ltoreq.t.sub.k(m+1) } of the LD signals for a selected time interval, a putative source asserted location L(t".sub.k(m) ;ps) for a time t".sub.k(m) in the selected time interval, and other identifying parameters. The augmented data signal is received by a central station that analyzes the LD signal segments and determines whether the asserted location L(t".sub.k(m) ;ps) is likely to be the true message source location. Part or all of the augmented data signal can be encrypted for transmission. One application is validation of use of licensed software on a computer whose location may be mobile. Another application is validation of votes cast from a plurality of remote voting sites.
摘要:
A method for measuring positional changes of an object, including rotation about any or all of three axes, using linear accelerometers. There is disclosed a method of using a linear accelerometer to integrate two other 3D linear accelerometers in order to measure and supply for further use six-dimensional information, that is, translation in three dimensions and rotation about three axes. Two linear accelerometer sensors are used to determine all but one of the variables in the six degrees of freedom. Output from a third accelerometer generates the data need to determine a sixth, rotational, degree of freedom. The need for a gyroscope for detecting changes in heading (i.e., yaw of azimuth) may therefore be avoided.
摘要:
Method and apparatus for reducing the contributions of receiver noise signal error and multipath signal error from signals received in a Satellite Positioning System (SATPS) from one or more SATPS satellites by formation and appropriate filtering of differences of signals DD that are differences of SATPS signals received by the SATPS receiver/processor. A difference signal DD of code-phase-derived delta range signals and carrier-phase-derived delta range signals is formed, and this difference signal is passed through a first statistical processing filter with an associated time constant .tau.1 in the approximate range 50-[500] 100 sec, to produce smoothed or filtered signal with the estimated receiver noise error reduced or removed. The difference signal DD is passed through second and third statistical processing filters having associated time constants .tau.2=5-20 sec and .tau.3=50-[500] 1000 sec, and the difference of the output signals of the second and third statistical processing filters is formed and subtracted from DD to form a new difference signal. This new difference signal is passed through a fourth statistical processing filter with an associated time constant .tau.4=50-[500] 1000 sec, to produce a smoothed or filtered signal with the estimated multipath signal error and estimated receiver noise error reduced or removed.
摘要:
Method and apparatus for reducing the contributions of receiver noise signal error and multipath signal error from signals received in a Satellite Positioning System (SATPS) from one or more SATPS satellites by formation and appropriate filtering of differences of signals DD that are differences of SATPS signals received by the SATPS receiver/processor. A difference signal DD of code-phase-derived delta range signals and carder-phase-derived delta range signals is formed, and this difference signal is passed through a first statistical processing filter with an associated time constant .tau.1 in the approximate range 50-500 sec, to produce smoothed or filtered signal with the estimated receiver noise error reduced or removed. The difference signal DD is passed through second and third statistical processing filters having associated time constants .tau.2=5-20 sec and .tau.3=50-500 sec, and the difference of the output signals of the second and third statistical processing filters is formed and subtracted from DD to form a new difference signal. This new difference signal is passed through a fourth statistical processing filter with an associated time constant .tau.4=50-500 sec, to produce a smoothed or filtered signal with the estimated multipath signal error and estimated receiver noise error reduced or removed.
摘要:
Methods, apparatus, and systems for determining the relevance of points of interest for a user are described. An application server receives information about a user's location, and velocity, as well as other user preferences, and adjusts a search space and filters points of interest identifying those that are relevant to the user. The relevance of the points of interest are based on the user's route, location and velocity.
摘要:
Methods, apparatus, and systems for determining the relevance of points of interest for a user are described. An application server receives information about a user's location, and velocity, as well as other user preferences, and adjusts a search space and filters points of interest identifying those that are relevant to the user. The relevance of the points of interest are based on the user's route, location and velocity.
摘要:
The partial decoding algorithm for decoding the partially damaged differential SATPS messages and the decoding device is disclosed. The algorithm is based on the modified parity test. The information contained in the decoded messages is used for the high level differential SATPS testing.
摘要:
A method for compensating for temporary loss of differential GPS correction signals for a satellite, numbered j, during an IODE changeover interval. Differences .DELTA.e.sub.i (t;j;n+1,n)=e.sub.i (t;j;n+1)-e.sub.i (t;j;n) (i=1, . . . , I) are formed for I ephemeris parameters used to describe the ephemeris for the satellite (j) during IODE intervals number n+1 and n. These differences are approximated for a DGPS blank-out time interval, given by t(j;n+1).sub.IODE .DELTA.t.sub.rev,mob .ltoreq.t
摘要翻译:一种用于在IODE切换间隔期间补偿卫星的差分GPS校正信号的暂时丢失的方法,编号为j。 差异DELTA ei(t; j; n + 1,n)= ei(t; j; n + 1)-ei(t; j; n)(i = 1,...,I) 参数用于在IODE间隔数n + 1和n期间描述卫星的星历表(j)。 对于DGPS空白时间间隔,由t(j; n + 1)IODE DELTA trev,mob = t
摘要:
Signal acquisition assistance data is obtained for receiving devices such as wireless position assisted location devices seeking signals from any source, such as satellite vehicles and base stations. The data may be obtained from previously acquired data, based upon evaluation of changes in parameters such as time and location that may jeopardize validity. In some cases the data may be adjusted for the changes in parameters. Refined data may be calculated by a receiver using partial measurements of signal sets, particularly if the acquisition assistance data provided by a remote entity includes more distinct parameters than have typically been provided. New data need not be obtained until the validity of previous data expires due to limitations upon temporal extrapolation using Doppler coefficients, unless mobile station movement that cannot be compensated is detected, and jeopardizes validity of the previous data.
摘要:
A method for compensating for temporary loss of differential GPS correction signals for a satellite, numbered j, during an IODE changeover interval. Differences .DELTA.e.sub.i (t;j;n+1,n)=e.sub.i (t;j;n+1)-e.sub.i (t;j;n) (i=1, . . . , I) are formed for I ephemeris parameters used to describe the ephemeris for the satellite (j) during IODE intervals number n+1 and n. These differences are approximated for a DGPS blank-out time interval, given by t(j;n+1).sub.IODE .DELTA.t.sub.rev,mob .ltoreq.t
摘要翻译:一种用于在IODE切换间隔期间补偿卫星的差分GPS校正信号的暂时丢失的方法,编号为j。 差异DELTA ei(t; j; n + 1,n)= ei(t; j; n + 1)-ei(t; j; n)(i = 1,...,I) 参数用于在IODE间隔数n + 1和n期间描述卫星的星历表(j)。 对于DGPS空白时间间隔,由t(j; n + 1)IODE DELTA trev,mob = t