| 摘要 |
<p>A jam resistant, low-cost data link, wherein short burst messages are frequency-hopped on a message-by-message basis. The data link includes a transmitter and a receiver which initially are set at a common, predetermined frequency. The message transmitted during each burst includes encrypted data identifying the frequency at which the next message will be transmitted to enable the receiver to tune to that frequency. If the initial transmission is jammed, the transmitter and receiver are preprogrammed to change to a preset back-up frequency. The receiver will request retransmission before the next transmission frequency is changed if a received message is garbled.</p> |
