High Frequency (HF) Radio Automatic Link Establishment (ALE)

SPAWAR N03-143, Small Business Innovation and Research (SBIR), Phase I

OBJECTIVE:  Develop an application that increases the number of reliable High Frequency (HF) communications links for sites with a large population of legacy HF assets and a limited number of Automated Link Establishment (ALE) radios. 

DESCRIPTION: HF Communications is still a widely used and relied upon by US Naval fleet and shore activities, as well as the other armed services and civilian agencies. HF communications is used on US Navy Amphibious ships as a primary means of communication with embarked Marines ashore. Marine troops when ashore are often capable of to twelve simultaneous HFALE links, while the ship they are embarked on is only capable of two, or sometimes less, HFALE links. By making HF Communications more reliable and easier to establish the Fleet could also use HF Communications for inter-battle group communications, voice and data, freeing up desirable long haul bandwidth (i.e. SATCOM) for other uses. Most, if not all Navy ships, have some form of HF radios and they continue to be procured and installed on new and existing platforms.

Currently, HF communication links are established using a manual process where operators select link frequencies using a predetermined frequency plan or using frequency prediction algorithms. This frequency selection method does not always result in the best communications link since the selected frequency is not optimized for the existing environmental conditions. As a result, operators often encounter unreliable, and in the worst case, complete loss of communications.

The Navy is currently trying to solve this problem by deploying ALE capable HF radios. These radios are capable of automatically establishing the optimal communication link by selecting the frequency that maximizes the link reliability.   When ALE radios are not being used they are continuously broadcasting signals at various frequencies, which are received and recorded by other ALE capable radios. ALE radios use the link’s qualitative analysis to determine the best frequency to use when establishing communication links with other ALE radios.

PHASE I: Define the functional requirements for the application. Identify key technologies and communication elements that will be used for the initial implementation. Formulate an architecture and design for interface and control of the identified elements. Provide prototype Graphical User Interfaces (GUI).

The project began in September 2003.