Method for establishing a communication link for a mobile user in a high frequency HF communication system comprising at least one transmission site and at least one reception site, the two sites being remote from one another by a distance D and communicating via a communication network, comprising at least the following steps: • at the reception site, scanning the signals or frequencies of interest f int for a given communication using a wideband receiver configured for a listening band which is strictly broader than the instantaneous band of the maximum modulated signal possible, estimating the level of energy received on the scanned frequencies by a correlation computation of the received signals and detecting whether the signals received on said wide band receiver comprises a request to establish a communication link between the mobile user and the communication system, • when the signal comprises a request to establish a communication link, then transmitting this request to establish a link at the level of a transmitting equipment and to a control module HUB which checks whether the communication request has been detected within a fixed period, • when the request is not received within the fixed period, then the reception site goes into a listening and polling phase, • when the request has arrived within the fixed period,, the control module at the reception level checks whether it is possible to establish a communication link by querying the transmission site and checking that the transmission site has the resources for establishing the requested communication link and starting the communication process based on configuration information computed by the transmission site, otherwise returning to the step of scanning the received signals. • at the reception site, scanning the signals or frequencies of interest f int for a given communication using a wideband receiver configured for a listening band which is strictly broader than the instantaneous band of the maximum modulated signal possible, estimating the level of energy received on the scanned frequencies by a correlation computation of the received signals and detecting whether the signals received on said wide band receiver comprises a request to establish a communication link between the mobile user and the communication system, • when the signal comprises a request to establish a communication link, then transmitting this request to establish a link at the level of a transmitting equipment and to a control module HUB which checks whether the communication request has been detected within a fixed period, • when the request is not received within the fixed period, then the reception site goes into a listening and polling phase, • when the request has arrived within the fixed period,, the control module at the reception level checks whether it is possible to establish a communication link by querying the transmission site and checking that the transmission site has the resources for establishing the requested communication link and starting the communication process based on configuration information computed by the transmission site, otherwise returning to the step of scanning the received signals.