Some embodiments of the invention relate to generating correction information based on global or regional navigation satellite system (NSS) multiple-frequency signals observed at a network of reference stations, broadcasting the correction information, receiving the correction information at one or more monitoring stations, estimating ambiguities in the carrier phase of the NSS signals observed at the monitoring station(s) using the correction information received thereat, generating residuals, generating post-broadcast integrity information based thereon, and broadcasting the post-broadcast integrity information. Other embodiments relate to receiving and processing correction information and post-broadcast integrity information at NSS receivers or at devices which may have no NSS receiver, as well as to systems, NSS receivers, devices which may have no NSS receiver, processing centers, and computer programs. Some embodiments may for example be used for safety-critical applications such as highly-automated driving and autonomous driving.

Some embodiments of the invention relate to generating correction information based on global or regional navigation satellite system (NSS) multiple-frequency signals observed at a network of reference stations, broadcasting the correction information, receiving the correction information at one or more monitoring stations, estimating ambiguities in the carrier phase of the NSS signals observed at the monitoring station(s) using the correction information received thereat, generating residuals, generating post-broadcast integrity information based thereon, and broadcasting the post-broadcast integrity information. Other embodiments relate to receiving and processing correction information and post-broadcast integrity information at NSS receivers or at devices which may have no NSS receiver, as well as to systems, NSS receivers, devices which may have no NSS receiver, processing centers, and computer programs. Some embodiments may for example be used for safety-critical applications such as highly-automated driving and autonomous driving.

A GPS filter-setting method comprises collecting, by a GPS filter-setting server, terminal information of a user terminal and GPS signal receiving environment information, setting, by the GPS filter-setting server, a filtering parameter used to filter an invalid GPS signal in the user terminal based on the collected terminal information of the user terminal and the GPS signal receiving environment information and transmitting, by the GPS filter-setting server, the set filtering parameter to the user terminal.

A multipath suppression method based on a steepest descent method includes stripping, according to carrier Doppler shift information fed back by a phase-locked loop, a carrier from an intermediate-frequency signal input into a tracking loop; constructing, on the basis of the autocorrelation characteristics of a ranging code, a quadratic cost function related to a measurement deviation of the ranging code, the cost function being not affected by a multipath signal; and finally, designing a new tracking loop of the ranging code according to the quadratic cost function and the principle of the steepest descent method, such that the loop has a multipath suppression function without increasing the computational burden. Compared with a narrow-distance correlation method, the current method reduces computing resources by ⅓, the design and adjustment of parameters are simple and feasible, a multipath suppression effect is superior, and a high engineering application value is obtained.

A multipath suppression method based on a steepest descent method includes stripping, according to carrier Doppler shift information fed back by a phase-locked loop, a carrier from an intermediate-frequency signal input into a tracking loop; constructing, on the basis of the autocorrelation characteristics of a ranging code, a quadratic cost function related to a measurement deviation of the ranging code, the cost function being not affected by a multipath signal; and finally, designing a new tracking loop of the ranging code according to the quadratic cost function and the principle of the steepest descent method, such that the loop has a multipath suppression function without increasing the computational burden. Compared with a narrow-distance correlation method, the current method reduces computing resources by ⅓, the design and adjustment of parameters are simple and feasible, a multipath suppression effect is superior, and a high engineering application value is obtained.

A method for detecting a presence of interference during global navigation satellite system (GNSS)-based and inertial sensor signals (INS)-based localization of a vehicle includes determining localization results using a first filter configured to read in GNSS data and INS data, and storing a plurality of the determined localization results. The plurality of the determined localization results are after one another in terms of time and are each determined using the first filter. The method further includes analyzing the stored plurality of localization results using a second filter which differs from the first filter.

A multipath suppression method based on a steepest descent method includes stripping, according to carrier Doppler shift information fed back by a phase-locked loop, a carrier from an intermediate-frequency signal input into a tracking loop; constructing, on the basis of the autocorrelation characteristics of a ranging code, a quadratic cost function related to a measurement deviation of the ranging code, the cost function being not affected by a multipath signal; and finally, designing a new tracking loop of the ranging code according to the quadratic cost function and the principle of the steepest descent method, such that the loop has a multipath suppression function without increasing the computational burden. Compared with a narrow-distance correlation method, the current method reduces computing resources by ⅓, the design and adjustment of parameters are simple and feasible, a multipath suppression effect is superior, and a high engineering application value is obtained.

A multipath suppression method based on a steepest descent method includes stripping, according to carrier Doppler shift information fed back by a phase-locked loop, a carrier from an intermediate-frequency signal input into a tracking loop; constructing, on the basis of the autocorrelation characteristics of a ranging code, a quadratic cost function related to a measurement deviation of the ranging code, the cost function being not affected by a multipath signal; and finally, designing a new tracking loop of the ranging code according to the quadratic cost function and the principle of the steepest descent method, such that the loop has a multipath suppression function without increasing the computational burden. Compared with a narrow-distance correlation method, the current method reduces computing resources by ⅓, the design and adjustment of parameters are simple and feasible, a multipath suppression effect is superior, and a high engineering application value is obtained.

A demodulator comprises a first-stage carrier demodulator and a second-stage carrier demodulator. The first-stage carrier demodulator is configured to remove or compensate for the tracking error in the baseband signal, where the tracking error comprises aggregate, channel tracking error of carrier phase for the same received band, sub-band, (baseband) GNSS satellite channel, or set GNSS channels. The second stage carrier demodulator is configured to remove or strip a carrier signal component without any unwanted image or carrier-related frequency artifacts and to prepare for correlation-based decoding or demodulation of the encoded baseband signal by the correlators. First correlators are configured to determine correlations for code phase tracking loop, where the code phase tracking loop is configured to estimate a corresponding code error component of the tracking error for the code local oscillator for a respective channel. Secondary correlators are configured to determine correlations for a carrier phase tracking loop, where the carrier phase tracking loop configured to estimate a corresponding aggregate feedback error for multiple channels or a set of channels.

Methods and systems are provided for navigating a mobile platform in an environment. A processor obtains information about an object in the environment, obtains information about a first satellite, and estimates a probability indicator for a non-line of sight signal transmission between a current satellite location of the first satellite and a current location of the mobile platform using the information about the first satellite and the information about the object. The processor further determines a discrepancy indicator using a movement information of the mobile platform and a movement information of the first satellite such that a weighting indicator can be determined using the estimated probability indicator and the determined discrepancy indicator. The processor then assigns a weighting indicator to a satellite signal transmitted from the first satellite in order to provide a first weighted signal for navigating the mobile platform.