Method and apparatus for providing an integrated communications, navigation and surveillance satellite system

A method of providing improved accuracy in determining a position of an object by monitoring ionospheric delay experienced by a signal traveling through an ionosphere and correcting for the ionospheric delay, the method comprising the steps of:

• providing a plurality of time synchronized satellites with each satellite of the plurality of satellites broadcasting multiple navigation signals and being capable of two-way communication with other devices;
• providing a network so that each satellite of the plurality of satellites is capable of communicating with any other satellite of the plurality of satellites;
• providing at least one user device capable of two-way communication with any satellite of the plurality of satellites that are within a line of sight of the at least one user device and of two way communication with any satellite of the plurality of satellites via the network;
• broadcasting a dual frequency surveillance signal from the at least one user device;
• receiving the dual frequency surveillance signal on each satellite of the plurality of satellites within the line of sight of the at least one user device;
• calculating a correction factor for each satellite of the plurality of satellites that received the dual frequency surveillance signal by using the received dual frequency surveillance signal to correct for ionospheric induced time delays caused by the ionosphere in signals traveling between the at least one user device and each satellite of the plurality of satellites that received the surveillance signal;
• transmitting from at least one satellite of the plurality of satellites to the at least one user device the correction factor for each satellite of the plurality of satellites that received the surveillance signal;
• receiving the correction factors by the at least one user device so that the at least one user device can correct for the time delays in navigation signals broadcast from each satellite of the plurality of satellites for which a correction factor was calculated;
• correcting each navigation signal received by the at least one user device for which a correction factor was received;
• and
• determining a position of the at least one user device based on the navigation signals received by the at least one user device and the corrections made to the navigation signals.

A method of determining a position of an object, the method comprising the steps of:

• providing a plurality of time synchronized satellites with each satellite of the plurality of satellites broadcasting multiple navigation signals and being capable of two-way communication with other devices;
• providing a network so that each satellite of the plurality of satellites is capable of communicating with any other satellite of the plurality of satellites;
• providing at least one user device capable of direct two-way communication with any satellite of the plurality of satellites that are within a line of sight of the at least one user device and of two way communication with any satellite of the plurality of satellites through the network;
• receiving at least one of the navigation signals broadcast from each satellite of the plurality of satellites that are within the line of sight of the at least one user device by the at least one user device;
• calculating a position of the at least one user device based on the received navigation signal(s);
• broadcasting from the at least one user device the calculated position of the at least one user device along with broadcasting a surveillance signal;
• receiving the broadcast position of the at least one user device and the surveillance signal by at least three satellites of the plurality of satellites;
• calculating the position of the at least one user device based on the surveillance signals received by the at least three satellites of the plurality of satellites;
• comparing the two calculated positions of the at least one user device;
• and
• transmitting to the at least one user device the position of the at least one user device calculated based upon the received surveillance signals if the two calculated positions differ by more than a predetermined amount.

A method of determining the position of an object when navigation signals being broadcast from a plurality of satellites are not being received, the method comprising the steps of:

• providing a plurality of time synchronized satellites with each satellite of the plurality of satellites broadcasting multiple navigation signals and being capable of two-way communication with other devices;
• providing a network so that each satellite of the plurality of satellites is capable of communicating with any other satellite of the plurality of satellites;
• providing at least one user device capable of direct two-way communication with each satellite of the plurality of satellites within a line of sight of the at least one user device and of two way communication with any satellite of the plurality of satellites through the network;
• broadcasting from the at least one user device a surveillance signal along with a message signal indicating that the at least one user device is not receiving the broadcast navigation signals when the at least one user device is not receiving at least one of the broadcast navigation signals;
• receiving the surveillance signal along with the message signal by each satellite of the plurality of satellites within the line of sight of the at least one user device;
• calculating a position of the at least one user device based on the received surveillance signals;
• and
• broadcasting from at least one satellite of the plurality of satellites to the at least one user device the calculated position of the at least one user device.

A system for providing integrated communications, navigation and surveillance information, the system comprising:

• a space segment having a plurality of satellites with synchronized time, each satellite of the plurality of satellites broadcasting multiple navigation signals and each satellite of the plurality of satellites being capable of two way communication and of receiving and relaying surveillance signals, and each satellite of the plurality of satellites being part of a network, the network allowing each satellite of the plurality of satellites to communicate with any other satellite of the plurality of satellites;
• a user segment having at least one mobile user device, the at least one user device being capable of direct two way communication with each satellite of the plurality of satellites that are within a line of sight of the least one user device and of two way communication with any satellite of the plurality of satellites through the network, the at least one user device being capable of receiving at least one of the navigation signals broadcast by the plurality of satellites and using the received navigation signal(s) to compute a position of the at least one user device, and the at least one user device being capable of broadcasting a surveillance signal to the plurality of satellites;
• a terrestrial segment having a processing apparatus that is capable of two way communication with any satellite of the plurality of satellites through the network, the processing apparatus being capable of receiving surveillance signals relayed by the plurality of satellites and determining a position of the at least one user device that broadcast the surveillance signal;
• and
• wherein the at least one user device communicates the position of the at least one user device computed by the at least one user device to the plurality of satellites along with a surveillance signal, the processing apparatus computes the position of the at least one user device based on the surveillance signal and compares the two computed positions, and the processing apparatus performs a system integrity check if the two computed positions differ by more than a predetermined amount.

A system for providing integrated communications, navigation and surveillance information, the system comprising:

• a space segment having a plurality of satellites with synchronized time, each satellite of the plurality of satellites broadcasting multiple navigation signals and each satellite of the plurality of satellites being capable of two way communication and of receiving and relaying surveillance signals, and each satellite of the plurality of satellites being part of a network, the network allowing each satellite of the plurality of satellites to communicate with any other satellite of the plurality of satellites;
• a user segment having at least one mobile user device, the at least one user device being capable of direct two way communication with each satellite of the plurality of satellites that are within a line of sight of the least one user device and of two way communication with any satellite of the plurality of satellites through the network, the at least one user device being capable of receiving at least one of the navigation signals broadcast by the plurality of satellites and using the received navigation signal(s) to compute a position of the at least one user device, and the at least one user device being capable of broadcasting a surveillance signal to the plurality of satellites;
• a terrestrial segment having a processing apparatus that is capable of two way communication with any satellite of the plurality of satellites through the network, the processing apparatus being capable of receiving surveillance signals relayed by the plurality of satellites and determining a position of the at least one user device that broadcast the surveillance signal;
• and
• wherein the at least one user device communicates the position of the at least one user device computed by the at least one user device to the plurality of satellites along with a surveillance signal, the processing apparatus computes the position of the at least one user device based on the surveillance signal and compares the two computed positions, and the processing apparatus communicates to the at least one user device via the network the position of the at least one user device computed by the processing apparatus if the two computed positions differ by more than a predetermined amount.

A system for providing integrated communications, navigation and surveillance information, the system comprising:

• a space segment having a plurality of satellites with synchronized time, each satellite of the plurality of satellites broadcasting multiple navigation signals and each satellite of the plurality of satellites being capable of two way communication and of receiving and relaying surveillance signals, and each satellite of the plurality of satellites being part of a network, the network allowing each satellite of the plurality of satellites to communicate with any other satellite of the plurality of satellites;
• a user segment having at least one mobile user device, the at least one user device being capable of direct two way communication with each satellite of the plurality of satellites that are within a line of sight of the least one user device and of two way communication with any satellite of the plurality of satellites through the network, the at least one user device being capable of receiving at least one of the navigation signals broadcast by the plurality of satellites and using the received navigation signal(s) to compute a position of the at least one user device, and the at least one user device being capable of broadcasting a surveillance signal to the plurality of satellites;
• a terrestrial segment having a processing apparatus that is capable of two way communication with any satellite of the plurality of satellites through the network, the processing apparatus being capable of receiving surveillance signals relayed by the plurality of satellites and determining a position of the at least one user device that broadcast the surveillance signal;
• and
• wherein the at least one user device informs the plurality of satellites that the at least one user device is not receiving the at least one navigation signal the at least one user device is capable of receiving whenever the at least one user device is not receiving the at least one navigation signal broadcast by the plurality of satellites and the processing apparatus computes the probable location of an interference source that is preventing the at least one user device from receiving the at least one navigation signal.

A method of determining a position of an object, the method comprising the steps of:

• providing a plurality of time synchronized satellites with each satellite of the plurality of satellites broadcasting multiple navigation signals and being capable of two-way communication with other devices;
• providing a network so that each satellite of the plurality of satellites is capable of communicating with any other satellite of the plurality of satellites;
• providing at least one user device capable of direct two-way communication with any satellite of the plurality of satellites that are within a line of sight of the at least one user device and of two way communication with any satellite of the plurality of satellites through the network;
• receiving at least one of the navigation signals broadcast from each satellite of the plurality of satellites that are within the line of sight of the at least one user device by the at least one user device;
• calculating a position of the at least one user device based on the received navigation signal(s);
• broadcasting from the at least one user device the calculated position of the at least one user device along with broadcasting a surveillance signal;
• receiving the broadcast position of the at least one user device and the surveillance signal by at least three satellites of the plurality of satellites;
• calculating the position of the at least one user device based on the surveillance signals received by the at least three satellites of the plurality of satellites;
• comparing the two calculated positions of the at least one user device;
• and
• performing an integrity check of the plurality of satellites if the two calculated positions differ by more than a predetermined amount.