Abstract: A universal multi-channel receiver for receiving and processing signals from different navigation systems is provided. The universal receiver is implemented as an ASIC receiver with a number of universal channels. The receiver with universal channels is capable of receiving and processing signals from navigation satellites located within a direct access zone. The universal receiver has a plurality of channels that share the same memory. The universal receiver can determine its coordinates using any of the existing navigation systems (GPS, GLONASS, Beidou and GALILEO). The receiver can receive and process any (PN) signals.

Abstract: A method for receiving and processing satellite navigation signals includes receiving the navigation signals; converting the navigation signals into digital signals; providing a clock signal to all channels that process the digital signals; generating frequency division signals; selecting a channel frequency division signal from the frequency division signals based on which ADC is used to convert the satellite navigation signals into digital signals; connecting the channel to the ADC; generating code frequency signal and base carrier frequency signal using a net accumulation signal; processing the digital signal in the channel to produce digital quadrature signal components of the digital signal based on the code frequency signal and the base carrier frequency signal; using a tick signal that represents 2N×clock signal as a temporary time scale for control of the channels for determining digital signal phase differences between the channels; and outputting coordinates based on the quadrature components.

Abstract: GNSS receiver includes first type correlators and a maximum selecting unit selecting an output from the first type correlators, and with a common control of all the correlators in code delay, carrier phase and carrier frequency; second type correlators with individual control in code delay of each correlator or each sub-group of second type correlators and with common control of all second type correlators in carrier phase and frequency; and a processor. The first type correlators can convolve one quadrature only, and demodulates CSK symbols, the second type correlators calculate discriminator values for CSK-modulated signal DLL, the demodulated data then is used by the processor to produce improved position and velocity.

Abstract: The present invention discloses methods of accuracy improving for code measurements in GLONASS GNSS receivers. One component of error budget in code measurements of GLONASS receivers is caused by a difference in signal delays arising in the receiver analog Front End and antenna filter on different channel frequencies specific to GLONASS satellites. Methods to compensate for differences in delays for different GLONASS channel frequencies have been proposed using data collected from a GLONASS signals simulator.

Abstract: A method for demodulating and tracking of CSK-modulated signals comprising the steps of receiving a CSK-modulated signal at a plurality of correlators, the CSK-modulated signal including a transmitted symbol; convolving the CSK-modulated signal with a preset reference replica of the CSK-modulated signal for N shifts (D1 . . . DN) of a PRN code relative to an internal receiver clock corresponding to N possible code shifts in the transmitted symbol, and M other code shifts (T1 . . . TM), where M<N, that satisfies D1??T?Ti?DN+?T for all Ti from (T1 . . . TM); selecting one of the N shifts (DMAX) where the convolution is a maximum; adjusting a CSK-signal Delay Locked Loop (DLL) based on a ratio of convolution values for the shifts DMAX and Ti for all Ti for which a modulus |DMAX?Ti| is smaller than a predefined threshold; and determining a value of the transmitted symbol based on DMAX.

Abstract: A method for receiving and processing satellite navigation signals includes receiving the navigation signals; converting the navigation signals into digital signals; providing a clock signal to all channels that process the digital signals; generating frequency division signals; selecting a channel frequency division signal from the frequency division signals based on which ADC is used to convert the satellite navigation signals into digital signals; connecting the channel to the ADC; generating code frequency signal and base carrier frequency signal using a net accumulation signal; processing the digital signal in the channel to produce digital quadrature signal components of the digital signal based on the code frequency signal and the base carrier frequency signal; using a tick signal that represents 2N×clock signal as a temporary time scale for control of the channels for determining digital signal phase differences between the channels; and outputting coordinates based on the quadrature components.

Abstract: Position determination for a mobile station is achieved through the modification of certain Wi-Fi access point and station signals, that are radiated by a certain master (i.e., guiding) base station, combined with slave (i.e., guided) stations having known coordinates, and processing the signals received from these base stations at the mobile station to determine the desired position.

Abstract: A method for receiving and processing satellite navigation signals includes receiving the navigation signals; converting the navigation signals into digital signals; providing a clock signal to all channels that process the digital signals; generating frequency division signals; selecting a channel frequency division signal from the frequency division signals based on which ADC is used to convert the satellite navigation signals into digital signals; connecting the channel to the ADC; generating code frequency signal and base carrier frequency signal using a net accumulation signal; processing the digital signal in the channel to produce digital quadrature signal components of the digital signal based on the code frequency signal and the base carrier frequency signal; using a tick signal that represents 2N×clock signal as a temporary time scale for control of the channels for determining digital signal phase differences between the channels; and outputting coordinates based on the quadrature components.

Abstract: A universal multi-channel receiver for receiving and processing signals from different navigation systems is provided. The universal receiver is implemented as an ASIC receiver with a number of universal channels. The receiver with universal channels is capable of receiving and processing signals from navigation satellites located within a direct access zone. The universal receiver has a plurality of channels that share the same memory. The universal receiver can determine its coordinates using any of the existing navigation systems (GPS, GLONASS, Beidou and GALILEO). The receiver can receive and process any (PN) signals.

Abstract: Position determination for a mobile station is achieved through the modification of certain Wi-Fi access point and station signals, that are radiated by a certain master (i.e., guiding) base station, combined with slave (i.e., guided) stations having known coordinates, and processing the signals received from these base stations at the mobile station to determine the desired position.

Abstract: A method for demodulating and tracking of CSK-modulated signals comprising the steps of receiving a CSK-modulated signal at a plurality of correlators, the CSK-modulated signal including a transmitted symbol; convolving the CSK-modulated signal with a preset reference replica of the CSK-modulated signal for N shifts (D1 . . . DN) of a PRN code relative to an internal receiver clock corresponding to N possible code shifts in the transmitted symbol, and M other code shifts (T1 . . . TM), where M<N, that satisfies D1??T?Ti?DN+?T for all Ti from (T1 . . . TM); selecting one of the N shifts (DMAX) where the convolution is a maximum; adjusting a CSK-signal Delay Locked Loop (DLL) based on a ratio of convolution values for the shifts DMAX and Ti for all Ti for which a modulus |DMAX?Ti| is smaller than a predefined threshold; and determining a value of the transmitted symbol based on DMAX.

Abstract: An apparatus to measure signal-to-thermal noise ratio (SNR) and signal-to-pulse noise ratio (SPNR), the apparatus including a quadrature mixer, a pulse noise reduction unit, an SNR estimation unit and an offset compensation unit, connected in series, the quadrature mixer receiving the input radio signal and outputting an in-phase component and a quadrature component; a pulse noise separation unit, and an SPNR estimation unit connected series, the pulse noise reduction unit and the pulse noise separation unit inputting the in-phase and quadrature components; the SPNR estimation unit inputting a filtered in-phase component from the pulse noise reduction unit. The offset compensation unit outputs a current SNR. The SPNR estimation unit outputs a current SPNR. The pulse noise separation unit includes a first LPF, an impulse noise separator and an HPF, connected in series; and a second LPF, a pulse noise detection unit and an inverter, connected in series.

Abstract: Method of identification and compensation for inversion of the input bit stream when decoding LDPC codes includes obtaining a code word of the LDPC code from a demodulator output and writing the code word into a buffer memory, decoding the code word, calculating a syndrome for each iteration when decoding, making an analysis of converging the weight of the syndrome, generating an inversion feature for the input bit stream based on this analysis, continuing the decoding, if the inversion feature for the input bit stream does not give evidence of detecting inversion, resetting, if the inversion feature for the input bit stream shows inversion, the LDPC decoder and analysis parameters for the convergence of the weight of the syndrome, reading next code word from the buffer memory, and producing an inversion of this code word, and feeding the word to the decoder input to implement the next decoding operation.

Abstract: Apparatus to measure signal-to-thermal noise ratio (SNR) and signal-to-pulse noise ratio (SPNR) includes a pulse noise reduction unit, an SNR estimation unit and an offset compensation unit; a pulse noise separation unit, and an SPNR estimation unit. Pulse noise separation unit includes (i) a first low pass filter (LPF), an impulse noise separator and a high pass filter (HPF), connected in series; and (ii) a second LPF, a pulse noise detection unit and an inverter. Pulse noise detection unit includes two channels, each with a high pass filter, an absolute value calculation unit, a low pass filter, a comparator, a pulse generator. The channels connect to OR gate, which outputs a pulse detection signal. Pulse noise reduction unit and pulse noise separation unit input in-phase and quadrature components. The SPNR estimation unit inputs a filtered in-phase component. The offset compensation unit outputs SNR, and the SPNR estimation unit outputs SPNR.

Abstract: A method for receiving and processing satellite navigation signals includes receiving the navigation signals; converting the navigation signals into digital signals; providing a clock signal to all channels that process the digital signals; generating frequency division signals; selecting a channel frequency division signal from the frequency division signals based on which ADC is used to convert the satellite navigation signals into digital signals; connecting the channel to the ADC; generating code frequency signal and base carrier frequency signal using a net accumulation signal; processing the digital signal in the channel to produce digital quadrature signal components of the digital signal based on the code frequency signal and the base carrier frequency signal; using a tick signal that represents 2N×clock signal as a temporary time scale for control of the channels for determining digital signal phase differences between the channels; and outputting coordinates based on the quadrature components.

Abstract: The present invention discloses methods of accuracy improving for code measurements in GLONASS GNSS receivers. One component of error budget in code measurements of GLONASS receivers is caused by a difference in signal delays arising in the receiver analog Front End and antenna filter on different channel frequencies specific to GLONASS satellites. Methods to compensate for differences in delays for different GLONASS channel frequencies have been proposed using data collected from a GLONASS signals simulator.

Abstract: Method of identification and compensation for inversion of the input bit stream when decoding LDPC codes includes obtaining a code word of the LDPC code from a demodulator output and writing the code word into a buffer memory, decoding the code word, calculating a syndrome for each iteration when decoding, making an analysis of converging the weight of the syndrome, generating an inversion feature for the input bit stream based on this analysis, continuing the decoding, if the inversion feature for the input bit stream does not give evidence of detecting inversion, resetting, if the inversion feature for the input bit stream shows inversion, the LDPC decoder and analysis parameters for the convergence of the weight of the syndrome, reading next code word from the buffer memory, and producing an inversion of this code word, and feeding the word to the decoder input to implement the next decoding operation.

Abstract: A navigation receiver operating in a differential navigation mode can change from one solution type to another. At each epoch, primary estimates of coordinates and the solution type are received. Each solution type has a corresponding accuracy. To improve the positioning quality when the solution type changes, smoothed estimates of coordinates are generated according to a two-branch algorithm. Two conditions are evaluated. If both conditions are satisfied, the current-epoch smoothed estimates of coordinates are set equal to the current-epoch extended estimates of coordinates calculated from the sum of the previous smoothed estimates of coordinates and coordinate increments calculated from carrier phases. If at least one of the conditions is not satisfied, updated smoothed estimates of coordinates are generated based on the sum of the current-epoch extended estimates of coordinates and a correction signal.

Abstract: Apparatus for estimating a current SNR of a signal, including an SNR estimator and an offset compensator connected in series, the offset compensator outputting the current SNR; the SNR estimator including (i) a first squaring unit, a summer, a square root unit, a first mean unit, a first subtractor, a scaling unit, a divider, a second subtractor and a decibel (dB)-recalculator, all connected in series, wherein an output of the second squaring unit is also connected to the divider; (ii) a third squaring unit connected to the first summer, and a second mean unit connected to an output of the summer at its input and to the subtractor at its output; and (iii) a correction calculator connected to the square root unit and to the second subtractor; the first squaring unit inputting an I component of the signal; and the second squaring unit inputting a Q component of the signal.

Abstract: A navigation receiver operably coupled to an antenna can determine location by receiving and processing radiofrequency navigation signals from global navigation satellites. The navigation receiver includes a quartz crystal oscillator that serves as a reference frequency source for a local oscillator signal that is mixed with the radiofrequency navigation signals to generate intermediate signals at intermediate frequencies lower than the radiofrequencies. In particular applications, the quartz crystal oscillator and the antenna are subjected to vibration and shock. A shift in the frequency or phase of the intermediate signals can result, and performance of phase-lock loops can degrade. Performance is improved with a phase-lock loop that processes a combination of individual channel control signals and common control signals.