Spectrum allocation method

A spectrum allocation method for a cellular network including a small cell network, the spectrum allocation method comprising:

• a) constructing a graph theory model of spectrum allocation including abstracting a cellular network into an interference pattern where each network node is abstracted and mapped to a vertex in the interference pattern, and an existing conflict or interference between two network nodes is mapped to the edge between two vertexes;
• b) establishing or updating a stakeholder list for each network node, the stakeholder list including information of a network node that cannot obtain the same spectrum resource unit of another network node established with the stakeholder list;
• a mapping vertex of the contained network node in the stakeholder list in the interference pattern, and a mapping vertex of the network node establishing the stakeholder list is linked by an edge;
• each network node calculates a largest value of maximal clique label of the interference pattern according to the stakeholder list;
• each network node transmits the established or the updated stakeholder list and the largest value of maximal clique label to other network nodes in the network;
• c) each network node listening periodically or triggered by an event for a status of the network, and if the number An of spectrum resource units obtained by a network node n is less than a lower bound value Kn, then the network node n selects more spectrum resource units until Kn spectrum resource units are obtained;
• where Kn is the total number of spectrum resource units obtained in the network and the largest value of maximal clique label of the network node and network node n includes at least one network node;
• if An≧Kn, and the number En of the spectrum resource units of the network node n being competed with the stakeholder list being equal to zero, the network node n competes for the remaining K′n−Kn spectrum resource units with a predetermined probability, until there is no free spectrum resource unit anymore;
• where K′n represents a upper bound value of the number of spectrum resource units being used by network node n;
• if An>Kn, and En>0, the network node n releases the spectrum resource units being competed;
• if An=Kn, and En>0, the network node n first releases the spectrum resource units being competed, and then selects K′n−Kn spectrum resource units not being competed in the spectrum resource units.