An OFDM Multi-User Spectrum Resource Allocation Algorithm Based on Joint Access Mechanism

Aiming at the problem of spectrum resource allocation of multi-cognitive users in CR-OFDM systems, this paper proposes a joint subcarrier and power allocation method based on access mechanism. In addition, the cognitive user's interference to the primary user communication is defined as the opportunity interference constraint. The algorithm first allocates subcarriers, takes into account the different communication needs of each cognitive user in the allocation, and introduces an on-demand allocation scale factor to ensure the fairness of spectrum resource allocation. Then, when the subcarrier allocation is completed, add a power lower bound constraint to each subcarrier allocated by the cognitive user, through a ladder algorithm to complete the power allocation optimization of the subcarrier finally. Simulation results show that the proposed algorithm not only ensures the fairness of capacity allocation among cognitive users but also guarantees the communication quality of each user. In addition, the proposed algorithm is more suitable for practical application background due to the introduction of opportunities to interfere with constraints.