The characteristic function of the K-distributed interference

Several types of electromagnetic interference as well as ultrasound backscatter signals can be accurately modelled by K-distribution. The probability density and cumulative distribution functions and expressions for moments of a K-distributed random variable are known. However, the form of the characteristic function has remained unsolved. Here, a closed form expression of the characteristic function of K-distribution is derived and investigated. Also, the form of the kernel for empirical characteristic function is examined in a view of designing a test for K-distribution.