Resource Optimization For Communication Link Of Multi-user Underwater Acoustic OFDM System

Effectively allocating subcarriers,power and other resources can bring higher communication capacity and performance to the system.Since the resources such as subcarriers and energy in the underwater wireless network are very valuable,if the resource optimization strategy is applied to the underwater acoustic OFDM system,the performance of the underwater acoustic communica-tion will be greatly improved.This paper focuses on designing resource optimization algorithms for underwater acoustic OFDM systems,and mainly allocates resources for the underwater acoustic OFDM communication link model under different access modes.The results obtained are mainly as follows:(1)For the OFDMA system,a method based on heuristic greedy algorithm for subcarrier allocation and then linearly distributing power is proposed.In the subcarrier allocation process,a"minimum rate request" method is defined as a basis for allocating sub-carriers to each receiver.In the power distribution process,the system meets the fairness requirements to a certain extent through an approximate proportional fairness method.Finally,the influence of communication signal-to-noise ratio on the communication speed of the three algorithms is analyzed by simulation.(2)For the NOMA system,a dynamic receiver matching mechanism is proposed.Then the sub-channels are allocated based on the greedy algorithm,and then the power allocation problem with non-convex optimization form is converted into geometric planning form by transforming the optimization target.The power allocation problem,using the interior point method to solve the power allocation problem in this form.Finally,the effectiveness of the proposed algorithm is proved by simulation.