A method comprising: identifying, by data processing hardware (118, 118a, 118b, 118g), a target platform (200, 300) for communication with a communication device (110, 200); establishing a communication connection between the target platform (200, 300) and the communication device (110, 200); identifying, by the data processing hardware (118, 118a, 118b, 118g), an available communication channel for communicating data between the target platform (200, 300) and the communication device (110, 200); modifying, by the data processing hardware (118, 118a, 118b, 118g), a communication signal by multiplying the communication signal with a pseudo random noise spreading code; and causing, by the data processing hardware (118, 118a, 118b, 118g), transmission of the modified communication signal from the communication device (110, 200) to the target platform (200, 300) through the available communication channel, the modified communication signal being transmitted below a thermal noise of the available communication channel; and wherein identifying the target platform (200, 300) comprises: tracking, by the data processing hardware (118, 118a, 118b, 118g), global positions of high altitude platforms (200, 300); determining, by the data processing hardware (118, 118a, 118b, 118g), a collection of high altitude platforms (200, 300) and available communication channels for transmitting the communication signal at a communication time of the transmission of the modified communication signal from the communication device (110, 200); and selecting, by the data processing hardware (118, 118a, 118b, 118g), the target platform (200, 300) from the collection of high altitude platforms (200, 300). identifying, by data processing hardware (118, 118a, 118b, 118g), a target platform (200, 300) for communication with a communication device (110, 200); establishing a communication connection between the target platform (200, 300) and the communication device (110, 200); identifying, by the data processing hardware (118, 118a, 118b, 118g), an available communication channel for communicating data between the target platform (200, 300) and the communication device (110, 200); modifying, by the data processing hardware (118, 118a, 118b, 118g), a communication signal by multiplying the communication signal with a pseudo random noise spreading code; and causing, by the data processing hardware (118, 118a, 118b, 118g), transmission of the modified communication signal from the communication device (110, 200) to the target platform (200, 300) through the available communication channel, the modified communication signal being transmitted below a thermal noise of the available communication channel; and wherein identifying the target platform (200, 300) comprises: tracking, by the data processing hardware (118, 118a, 118b, 118g), global positions of high altitude platforms (200, 300); determining, by the data processing hardware (118, 118a, 118b, 118g), a collection of high altitude platforms (200, 300) and available communication channels for transmitting the communication signal at a communication time of the transmission of the modified communication signal from the communication device (110, 200); and selecting, by the data processing hardware (118, 118a, 118b, 118g), the target platform (200, 300) from the collection of high altitude platforms (200, 300). tracking, by the data processing hardware (118, 118a, 118b, 118g), global positions of high altitude platforms (200, 300); determining, by the data processing hardware (118, 118a, 118b, 118g), a collection of high altitude platforms (200, 300) and available communication channels for transmitting the communication signal at a communication time of the transmission of the modified communication signal from the communication device (110, 200); and selecting, by the data processing hardware (118, 118a, 118b, 118g), the target platform (200, 300) from the collection of high altitude platforms (200, 300).