Automatic Sounding

telecommunication Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that ...

, automatic sounding is the testing of selected channels for quality by providing a very brief identifying transmission that may be used by other stations to evaluate connectivity, and

availability In reliability engineering, the term availability has the following meanings: * The degree to which a system, subsystem or equipment is in a specified operable and committable state at the start of a mission, when the mission is called for at ...

, and to identify known working channels for immediate or later use for

communications Communication (from la, communicare, meaning "to share" or "to be in relation with") is usually defined as the transmission of information. The term may also refer to the message communicated through such transmissions or the field of inquir ...

or calling. They are often used to maintain

connectivity Connectivity may refer to: Computing and technology * Connectivity (media), the ability of the social media to accumulate economic capital from the users connections and activities * Internet connectivity, the means by which individual terminal ...

in digital communications high frequency radio networks. Automatic soundings are primarily intended to increase the efficiency of the

automatic link establishment Automatic Link Establishment, commonly known as ALE, is the worldwide de facto standard for digitally initiating and sustaining HF radio communications. ALE is a feature in an HF communications radio transceiver system that enables the radio statio ...

(ALE) function, thereby increasing system

throughput Network throughput (or just throughput, when in context) refers to the rate of message delivery over a communication channel, such as Ethernet or packet radio, in a communication network. The data that these messages contain may be delivered ov ...

. In ALE, the sounding information consists of a heavily error-corrected short message identifying the sender. Recipients decode it and use the

bit error rate In digital transmission, the number of bit errors is the number of received bits of a data stream over a communication channel that have been altered due to noise, interference, distortion or bit synchronization errors. The bit error rate (BER) i ...

to calculate and store a (channel, node, quality)

tuple In mathematics, a tuple is a finite ordered list (sequence) of elements. An -tuple is a sequence (or ordered list) of elements, where is a non-negative integer. There is only one 0-tuple, referred to as ''the empty tuple''. An -tuple is defi ...

. As ionospheric conditions and mobile-node locations change, these quality tuples will shift. The stored data can be used to maximize the chance that the best channel to link with a given partner will be chosen first. {{DEFAULTSORT:Automatic Sounding Communication circuits Radio frequency propagation fading