Method for Shifting Communications of a Terminal Located on a Moving Platform from a First to a Second Satellite Antenna Beam

Abstract

A method for shifting communications of a terminal located on a moving platform from a first satellite beam to a second satellite beam comprises determining a time for initiation of a beam shift from the first satellite beam to the second satellite beam; executing a first beam shift from the first satellite beam to the second satellite beam; and executing a second beam shift from the first satellite beam to the second satellite beam, wherein the first and second beam shifts are performed using a switch matrix.

Description

[0001]This application claims the priority benefit of U.S. provisional application Ser. No. 61 / 764,040, filed on 13 Feb. 2013, the contents of which are incorporated by reference in their entirety.BACKGROUND OF THE INVENTION[0002]Many airlines offer passengers the ability to engage in wireless communications in flight, such as using a personal laptop or tablet computer to access websites or E-mail services. These wireless communications can take place over wife and over a satellite link to a terrestrial gateway antenna.[0003]When communicating using a terminal located on a moving platform (such as an aircraft) covering large distances, the use of conventional satellites having wide beam coverage can provide for continuous connection for an extended period of time. When switching from one satellite to another, or for multi-beam satellites, from one satellite beam to another, the connection can be lost, and this down time is typically of the order of minutes. Although continuous conti...

AI Technical Summary

Benefits of technology

[0013]The invention can determine the connection quality of a prospective beam switch prior to completing the beam switch. That is, the invention examines the quality of the connection to the second satellite beam prior to a beam switch. If the connection quality is high, (for example, if there is little chance of a dropped connection upon switching to the second beam), the invention will undergo the beam switch. If the quality of the connection to the second beam is below a predetermined threshold, for example, due to noise, the invention will not undergo the beam switch and will revert back to the first satellite beam. In this manner, the invention seeks to maintain a high quality connection to minimize outages or gaps in coverage.

[0020]A user application on the terminal can be connected to either the first or second demodulator, whichever is active with respect to connecting the application traffic flow, through a command controllable switch, a non-manual switch connected to the controller software which controls the hardware of the switch. Such an embodiment allows for ready control of the beam switching process.

[0021]Each satellite can be equipped with a software engine and control function connected to respective on-board processors and switch matrixes and / or channelizers. Similarly, the terminal can be equipped with a terminal software engine and control function, and the respective software engines and control functions of the system can be synchronized with each other and configured to generate and transmit the switch command to execute the shifting of the communications signal. Such embodiments allow for efficient synchronization of a beam shift.

[0025]The system can also be configured to gather information from various sources, such as from communications traffic flowing through a network comprising the system, from an onboard processor and a network operations center, and / or from sensors such as ground sensors or atmospheric sensors about issues affecting signal conditions, and to inform users in real time thereof. That is, the system in the satellite may gather information from various sensors located at any place on the ground or in the atmosphere to acquire data about problems affecting link conditions, such as weather and other local effects, and can inform mobile users in the system, with effectively no delay, about such local problems. Users can then take whatever action may be advisable, such as changing their route, and thereby avoiding loss of communication caused by any potential problems.

[0026]The system can also be configured so as to provide flight control executed from the satellite which optimizes communications capacity at all times. That is, the system can comprise computer instructions and flight control configured to maintain optimized communications signal capacity and quality during travel of the moving platform. In this regard, the system is operationally linked to the flight control system so that the moving platform remains in a flight path which provides optimal signal quality.

Problems solved by technology

When switching from one satellite to another, or for multi-beam satellites, from one satellite beam to another, the connection can be lost, and this down time is typically of the order of minutes.

Although continuous continental and intercontinental communications with wide-beam satellites can take place with a limited number of satellite changes, a drawback of wide beams is that they provide low power density and low sensitivity since the energy is spread / received from a wide area, making it impossible to support high data rates on the moving platform using small antennas.

The small spot beam size will cause a frequent need to move from one beam to another, and it is no longer acceptable to lose communication during such shifts.

Although some of the beam shifts can be pre-planned before the trip, such pre-planning can be very difficult since flight delays, changes of itinerary, and weather can affect the planned trip route.

Since the satellite operator does not know at all times which frequencies may be available in each beam, pre-planning is therefore complex and very inefficient.

The satellite operator does not want to reserve frequencies in particular beams unless these frequencies are paid for, thereby removing them from general usage and causing inefficient use of spectrum, as well as significantly increasing service costs.

If route planning takes place long before the actual trip, pre-planning which satellite frequencies to use becomes even more difficult, and communications become even more expensive since longer lead times may result in even further changes, both environmentally and on the satellite.

This reconnection can be a rather complicated process, and the communication line will be down until the connection to the second beam can be established.

In a multi-beam environment where the beam diameter on the ground is small, this reconnection problem grows since the mobile platform will need to shift beams quite often, especially when moving quickly such as in flight.

Images