T.F. Kapaeva - JSC «Concern «Sozvezdie». E-mail: kapaeva@sozvezdie.su
А.Е. Limarev - project director, JSC «Concern «Sozvezdie». E-mail: limarev@sozvezdie.su
Yu.N. Maksyuta - JSC «Concern «Sozvezdie». E-mail: maksyuta@sozvezdie.su
V.I. Shestopalov - Ph(D), JSC «Concern «Sozvezdie»

A time optimization algorithm for cyclic spectrum sensing in multiple antenna system is proposed. All antennas operate in the identical conditions. At the output of each antenna there is an energy detector, that can work either in the radiometer mode (i.e. only energy is measured) or in the detector mode (i.e. local decision about detection is made). In the first case, global solution is made in the fusion centre based on the sum energy. In the second case, the fusion centre makes global solution according to the «k-out-of-M» rule, where M is the general number of antennas, and k is the number of antennas with positive local solutions. Local detector characteristics are computed on the given global detection probability as a solution of the nonlinear equation of the M-th order. Taking into consideration the equation specific features, it is possible to reduce the equation root calculation problem to the beta-distribution quantile computing. Numerical calculations are implemented based on the proposed algorithm.