Method and system for sharing radio spectrum

A method for sharing spectrum in a communication network including at least one first network including first transmission systems S1 and one second network including second transmission systems S2, the first and the second networks working in frequency ranges that overlap at least partially and lie in one and the same geographic area, resulting in a sharing of a spectral band, the method comprising at least the following steps:

• affiliating at least a first transmission system and at least a second transmission system with a server and communicating spectrum sharing rules;
• determining whether there is a constrained system defined as having a fixed frequency band, and, when there is, assigning to said constrained system a first spectral sub-band of the shared spectral band, for a given geographic area, or generating an alarm when said assigning is not possible;
• performing said assigning for all geographic areas covered by said constrained system;
• and
• identifying non-constrained systems defined as having flexible frequency bands of variable widths and/or positions in the spectral band, and, by applying the communication spectrum sharing rules, assigning to each of the non-constrained systems and each defined geographic area, a spectral sub-band for each of the first and second transmission systems as a function of the geographic area covered by the communication network, and when said spectral sub-band cannot be found, generating another alarm.