The Computer-controlled Shortwave Adaptive Data Transmission / Voice Compatible With The Communications Network To Achieve

The short-wave telecommunication is based on the electromagnetic wave's reflection on the ionosphere. The ionosphere itself is time-varying, so the application of short-wave communication was restricted greatly. The adaptive short-wave communication technique that appeared at the end of 1980's solved the problems of frequency selection and automatic link establishing, thus made a great progress in short-wave telecommunication.Most adaptive short-wave communication systems now used follow the USA federal standard FED-STD-1045. FED-STD-1045 is the standard of automatic link establishing (ALE). In order to make all radios conforming this standard communicate with each other, FED-STD-1045 formulates the wave pattern of ALE signals, the detection of channels and the rules of calling and service.Short-wave adaptive radio can be used not only to transport data but also to transmit voice signals. Additionally, after appending an Auto Standard Telephone Inter-connector to it, the radio can connect the shortwave network with Public Standard Telephone Network (PSTN), realizing cross-network talking.Based on the radios conforming the FED-STD-1045, this paper brings forward a method to construct a short-wave adaptive data/voice telecommunication system. This system is mainly used to transmit data, but it also supports voice transmission. It will improve the efficiency of shortwave telecommunication nets on the following aspects: the data/voice channel sharing in the whole system, automatic establishment and destruction of data/voice link and automatic switching between data and voice transmission.This system is composed with central stations and external stations. The central stations, which are the kernel nodes of the whole short-wave communication network, manage the channel resources and all requests of communication. The external stations, which are the periphery nodes of the...