Transmitting surveillance signals in response to a received signal

A method comprising:

• determining, by processing circuitry in a first instance, that a receiver has not received a command signal from a traffic management system;
• suppressing, by the processing circuitry, transmission of surveillance messages by a transmitter in response to determining that the receiver has not received the command signal;
• determining, by the processing circuitry in a second instance, that the receiver received the command signal from the traffic management system;
• and
• causing, by the processing circuitry, the transmitter to transmit the surveillance messages in response to determining that the receiver received the command signal.

A device comprising a computer-readable medium having executable instructions stored thereon, configured to be executable by processing circuitry for causing the processing circuitry to:

• determine, in a first instance, that a receiver has not received a command signal from a traffic management system;
• suppress transmission of surveillance messages by a transmitter in response to determining that the receiver has not received the command signal;
• determine, in a second instance, that the receiver received the command signal from the traffic management system;
• and
• cause the transmitter to transmit the surveillance messages in response to determining that the receiver received the command signal.