An illustrative embodiment disclosed herein is a method including determining, by a location server, a satellite constellation, a location of a target endpoint, and a next available time of the target endpoint. The method further includes determining, by the location server, a plurality of candidate satellites based on the satellite constellation, the location of the target endpoint, and the next available time of the target endpoint. The method further includes instructing, by the location server, a ground station to broadcast a downlink signal to the plurality of candidate satellites.

A wireless communication device according to some aspects includes an output determiner configured to determine first weighted signals for a plurality of antennas with first beamforming weights, a selector configured to select, from the plurality of antennas, a reference antenna based on signal powers of the first weighted signals, a weight controller configured to determine second beamforming weights for a predetermined number of antennas of the plurality of antennas based on a difference between the first weighted signal of the reference antenna and the first weighted signals of the predetermined number of antennas, the output determiner further configured to determine second weighted signals for the plurality of antennas with the second beamforming weights.

A method of receiving information is provided. The method, performed at a system for information transfer, includes receiving a signal pulse and determining a frequency band and a pulse duration associated with the signal pulse. The method includes, in accordance with a determination that the frequency band is one of a set of frequency bands, determining, from a first set of symbols, a first symbol associated with the frequency band. The method also includes, in accordance with a determination that the pulse duration is one of a set of pulse durations, determining, from a distinct second set of symbols, a second symbol associated with the pulse duration. Each frequency band in the set of frequency bands is associated with a respective symbol in the first set of symbols, and each pulse duration in the set of pulse durations is associated with a respective symbol in the second set of symbols.

A method of receiving information is provided. The method, performed at a system for information transfer, includes receiving a signal pulse and determining a frequency band and a pulse duration associated with the signal pulse. The method includes, in accordance with a determination that the frequency band is one of a set of frequency bands, determining, from a first set of symbols, a first symbol associated with the frequency band. The method also includes, in accordance with a determination that the pulse duration is one of a set of pulse durations, determining, from a distinct second set of symbols, a second symbol associated with the pulse duration. Each frequency band in the set of frequency bands is associated with a respective symbol in the first set of symbols, and each pulse duration in the set of pulse durations is associated with a respective symbol in the second set of symbols.

Methods, computer program products, and systems are presented. The method computer program products, and systems can include, for instance: examining one or more parameter characterizing a prospective connection of the mobile airborne article to first through Nth base stations, the one or more parameter including a Doppler shift; determining based on the examining that a criterion is satisfied, the criterion having one or more factor; and initiating handoff of the mobile airborne article to one of the first through Nth base stations based on the determining.

Methods, computer program products, and systems are presented. The method computer program products, and systems can include, for instance: examining one or more parameter characterizing a prospective connection of the mobile airborne article to first through Nth base stations, the one or more parameter including a Doppler shift; determining based on the examining that a criterion is satisfied, the criterion having one or more factor; and initiating handoff of the mobile airborne article to one of the first through Nth base stations based on the determining.

A method of receiving information is provided. The method is performed at a system for information transfer. The method includes receiving a first signal pulse and determining a first frequency band associated with the first signal pulse. The method includes, in accordance with a determination that the first frequency band is a respective frequency band in a predefined set of frequency bands, determining, from a predefined set of symbols, a first symbol associated with the first frequency band and represented by the first signal pulse. Each frequency band in the predefined set of frequency bands is associated with a distinct respective symbol in the predefined set of symbols, and frequency bands in the predefined set of frequency bands, in aggregate, are not contiguous.

A method of receiving information is provided. The method is performed at a system for information transfer. The method includes receiving a first signal pulse and determining a first frequency band associated with the first signal pulse. The method includes, in accordance with a determination that the first frequency band is a respective frequency band in a predefined set of frequency bands, determining, from a predefined set of symbols, a first symbol associated with the first frequency band and represented by the first signal pulse. Each frequency band in the predefined set of frequency bands is associated with a distinct respective symbol in the predefined set of symbols, and frequency bands in the predefined set of frequency bands, in aggregate, are not contiguous.

A method of receiving information is provided. The method is performed at a system for information transfer. The method includes receiving a first signal pulse and determining a first frequency band and a first pulse duration associated with the first signal pulse. The method includes, in accordance with a determination that the first frequency band is one of a predefined set of frequency bands, and that the first pulse duration is one of a predefined set of pulse durations, determining, from a predefined set of symbols, a first symbol associated with the first frequency band and the first pulse duration. Each frequency band in the predefined set of frequency bands is associated with a respective set of two or more symbols, and each symbol of a respective set of two or more symbols is associated with a distinct respective pulse duration in the first predefined set of pulse durations.

A method of receiving information is provided. The method is performed at a system for information transfer. The method includes receiving a first signal pulse and determining a first frequency band and a first pulse duration associated with the first signal pulse. The method includes, in accordance with a determination that the first frequency band is one of a predefined set of frequency bands, and that the first pulse duration is one of a predefined set of pulse durations, determining, from a predefined set of symbols, a first symbol associated with the first frequency band and the first pulse duration. Each frequency band in the predefined set of frequency bands is associated with a respective set of two or more symbols, and each symbol of a respective set of two or more symbols is associated with a distinct respective pulse duration in the first predefined set of pulse durations.