HF communications applications using new broadband architecture

Various applications made possible or enhanced by broadband architecture are described. A key feature is the ability to simultaneously transmit on many frequencies with only one antenna. In shipboard operation, the broadband architecture allows full duplex operation with closely spaced frequencies and with small physical spacing between the transmitting and the receiving antennas. Similarly, embassy-type systems can be designed using broadband architecture. The ease with which frequency diversity can be done with this type of system makes it attractive to HF users (in the 2-30 MHz band) with two or more assigned frequencies. Automatic link establishment (ALE) is a means by which an HF communications system can automatically determine the best frequency or frequencies for sensing information. The broadband architecture allows a fully automatic and unattended system to be designed. Broadband architecture makes it possible to design a diversity-hopping system for which effective countermeasures are difficult