Abstract: A method of receiving and decoding non-legacy GNSS signals and re-transmitting these in real-time as legacy GPS (L1-C/A) signals decoding into standard PVT/PNT information then re-encoding using a real-time GPS simulator as legacy GPS code signals, and outputting as a legacy GPS antenna signal. A navigational apparatus for performing the method may further include an Inertial Measurement Unit, Inertial Navigation System (IMU/INS) module and oscillator coupled to the GPS simulator for providing an inertial location signal supplementing the GNSS signal to the GPS simulator, wherein the GPS simulator encodes the RF simulated GPS signal based at least in part on the inertial location signal for a period when at least one of the GNSS signal or the PVT/PNT signal is not available.

Abstract: A method of receiving and decoding non-legacy GNSS signals and re-transmitting these in real-time as legacy GPS (L1-C/A) signals decoding into standard PVT/PNT information then re-encoding using a real-time GPS simulator as legacy GPS code signals, and outputting as a legacy GPS antenna signal. A navigational apparatus for performing the method may further include an Inertial Measurement Unit, Inertial Navigation System (IMU/INS) module and oscillator coupled to the GPS simulator for providing an inertial location signal supplementing the GNSS signal to the GPS simulator, wherein the GPS simulator encodes the RF simulated GPS signal based at least in part on the inertial location signal for a period when at least one of the GNSS signal or the PVT/PNT signal is not available.

Abstract: In one embodiment, the present invention includes a method of receiving and decoding military L2 or L1 P(Y) or M-Code signals and re-transmitting these in real-time as legacy L1-C/A signals. The decoding process of the P(Y) or M-code is done through the programming by the user of secret keys into an embodiment of this invention. These military code signals are then decoded into standard PVT/PNT information which are typically transmitted on an industry standard serial port and format, which are then re-encoded using a real-time GPS simulator sub-system as legacy L1-C/A code signals, and transmitted to the output of the embodiment of this invention as a standard antenna signal. This output signal could be made compatible with any commercial L1-C/A code GPS receiver, and may thus be decoded by the GPS receiver as if the signals had been received directly from the Satellites.

Abstract: In one embodiment, the present invention includes a method of correcting the frequency of a crystal oscillator. The method includes establishing an operating baseline for the crystal oscillator using a frequency reference, storing information in memory, and adjusting the frequency according to the information. The information corresponds to the operating baseline. Adjusting the frequency occurs in response to a power-on event and the absence of the frequency reference.

Abstract: In one embodiment, the present invention includes a method of correcting the frequency of a crystal oscillator. The method includes establishing an operating baseline for the crystal oscillator using a frequency reference, storing information in memory, and adjusting the frequency according to the information. The information corresponds to the operating baseline. Adjusting the frequency occurs in response to a power-on event and the absence of the frequency reference.

Abstract: In one embodiment, the present invention includes a method of correcting the frequency of a crystal oscillator. The method includes establishing an operating baseline for the crystal oscillator using a frequency reference, storing information in memory, and adjusting the frequency according to the information. The information corresponds to the operating baseline. Adjusting the frequency occurs in response to a power-on event and the absence of the frequency reference.

Abstract: In one embodiment, the present invention includes a method of correcting the frequency of a crystal oscillator. The method includes establishing an operating baseline for the crystal oscillator using a frequency reference, storing information in memory, and adjusting the frequency according to the information. The information corresponds to the operating baseline. Adjusting the frequency occurs in response to a power-on event and the absence of the frequency reference.