Abstract: A system for establishing and sustaining a broadband communication is provided wherein: the first master post is suitable for transmitting a known test sequence on a sub-band Bk to the second called post as soon as the said second called post acknowledges the receipt of a communication setup message on a frequency fi; the said second controller being suitable for determining quality scores on the Mk frequencies of the sub-band Bk and for transmitting the said values of quality to the first master post. The first master post is suitable for determining and for evaluating the capability of the sub-band Bk to respond to the SLA target service a sub-channel on the basis of the scores of qualities received, and for selecting the sub-band Bk which exhibits the required capability and thereafter for triggering the communication with the said second post. Application to HF broadband systems.

Abstract: A method is provided for transmitting data between a plurality of radio stations of one same network, each station having a transmitter and a receiver. The method includes a first transmission mode in which the network operates with frequency hopping in a first frequency plan, the frequency used for data transmission being maintained for a FH dwell time, and changing from one FH dwell time to another as per a law of frequency change; a second transmission mode in a second frequency plan in which a transmitter station (A) transmits data on a fixed frequency to a receiver station (B), the second mode comprising a step (120) to determine the fixed frequency, the determination step comprising the transmission of a test word on each frequency of the second plan for a respective test dwell time. The duration of the test dwell time is equal to the duration of the FH dwell time multiplied by an integer factor of value between 1 and 6.

Abstract: A system for establishing and sustaining a broadband communication is provided wherein: the first master post is suitable for transmitting a known test sequence on a sub-band Bk to the second called post as soon as the said second called post acknowledges the receipt of a communication setup message on a frequency fi; the said second controller being suitable for determining quality scores on the Mk frequencies of the sub-band Bk and for transmitting the said values of quality to the first master post. The first master post is suitable for determining and for evaluating the capability of the sub-band Bk to respond to the SLA target service a sub-channel on the basis of the scores of qualities received, and for selecting the sub-band Bk which exhibits the required capability and thereafter for triggering the communication with the said second post. Application to HF broadband systems.

Abstract: This method for transmitting data between a plurality of radio stations of one same network, each station having a transmitter and a receiver, comprises: a first transmission mode in which the network operates with frequency hopping in a first frequency plan, the frequency used for data transmission being maintained for a FH dwell time, and changing from one FH dwell time to another as per a law of frequency change; a second transmission mode in a second frequency plan in which a transmitter station (A) transmits data on a fixed frequency to a receiver station (B), the second mode comprising a step (120) to determine the fixed frequency, the determination step comprising the transmission of a test word on each frequency of the second plan for a respective test dwell time. The duration of the test dwell time is equal to the duration of the FH dwell time multiplied by an integer factor of value between 1 and 6.