摘要:
A method of recalibrating a Global Positioning System (GPS) receiver includes applying a first control signal to an oscillator for generation of an oscillator signal having an initial frequency and determining if an indicator of correct oscillator output frequency is present at the initial frequency. If an indicator of correct oscillator output frequency is not present, then iterative steps are followed until an indicator of correct oscillator output frequency is found. The iterative steps include: applying a new adjusted control signal to the oscillator for generation of a new frequency; determining whether an indicator of correct oscillator frequency is present; and if an indicator of correct oscillator output frequency is present with the oscillator having the new frequency, storing said adjusted control signal. If an indicator of correct oscillator frequency is present with the oscillator output signal having said initial frequency, then storing said initial control signal.
摘要:
A method and system for detecting GPS interference is disclosed. In one exemplary embodiment, a method for detecting interference in a Global Positioning System comprises the steps of receiving at least one satellite signal from one or more satellites in a Global Positioning System; identifying a noise floor value from the at least one satellite signal; identifying an interference signal based on the noise floor value; determining an interference value for the interference signal from the noise floor value wherein a level of the noise floor value corresponds to a level of interference; and providing the interference value to at least one user for informing the user of the interference signal.
摘要:
A base station (26) provides service in a satellite communications (SATCOM) system (22) to a terminal (24). The SATCOM system (22) operates in accordance with a first standard (43), and the terminal (24) is unable to communicate in accordance with the first standard (43). Methodology entails receiving, at a SATCOM resource controller (32), a request (62) for a satellite resource (46) from the base station (26). The satellite resource (46) is allocated to the base station (26) and the controller (32) sends a message (58) with the allocated satellite resource (46). The base station (26) applies a second standard (48), defining a specific set of functional and performance characteristics, to the satellite resource (46). The terminal (24) is enabled to perform satellite communications in accordance with the second standard (48) using the satellite resource (46).
摘要:
A communications system (20) includes a resource controller (22) and a terminal (24) in communication with the resource controller (22). Periodically, the resource controller (22) sends a service announcement (46) that identifies a set (50) of timeslots (52) within a communication resource (40) configured for random access within a future frame (42). The terminal (24) ascertains a burst characteristic (118) of a message (54) to be sent from the terminal (24) and generates a random access parameter (128). The terminal (24) selects one of the timeslots (52) from the set (50) in accordance with the random access parameter (128), the timeslot exhibiting a burst type (62) corresponding to the burst characteristic (118) of the message (54). The terminal (24) transmits the message (54) in the selected timeslot (52).
摘要:
Survival radio interrogator (1) transmits upon request a message including an identification of survival radio (3). Upon receiving and processing this message, survival radio (3) determines its position from the Global Positioning System and transmits a message back to the search aircraft (2) with the survival radio interrogator (1). The processor (10) of the survival radio interrogator 1 determines a range and bearing of the survival radio (3) and processes data from the survival radio 3 which data includes identification, position and messaging information for display on the LCD display 14. All message transmissions are conducted via the aircraft's (2) radio/intercom system (30).