The Method of Reducing the Simulation Time for Narrow and Asymmetric Jakes Spectrum Simulation

To meet the time autocorrelation performance requirement of the radio channel simulation, the required simulation time may be very long for the narrow and asymmetric Jakes spectrum simulation based on the ergodic sum-of–cisoids model. To reduce the required simulation time, in this paper, the time autocorrelation deviation function is analyzed to indicate that it has periodical local minimal values, which decrease monotonously. Meanwhile, these local minimal values are optimal and the corresponding time periods can be obtained conveniently, when the method of equal distance is applied to create the simulation model. Based on this analysis, an equal distance method based simulation model is propsoed by setting the simulation time to some specific value which is nearby the time period associated with specific local minimum values of the corresponding autocorrelation deviation function. Therefore, the resulted autocorrelation deviation function can approache its local minimal value with shortest simulation time requirement. The simulation resutls show that under the same time autocorrelation requirement, this propsoed method can reduce the simulation time length one order of magnitude than that of the existing methods.