Optimization of frequency assignment

A systematic method of determining carrier frequency assignment is proposed to minimize the cochannel interference in satellite communication systems. For the mathematical treatment of the problem, discrete positioning of carriers is introduced to avoid the nonlinear expression inherent in interference evaluation. The proposed method converts this nonlinear problem into the well-known assignment problem and enables the development of an algorithm based on the branch-and-bound method. Extended models of the proposed method are presented for practical application. To demonstrate the effectiveness of the method, computation results are shown for two typical problems. In both of the examples, cochannel interference is significantly reduced as the result of optimization of frequency assignment