Radio wave arrival status estimating system, its method and program

A radio wave arrival status estimation method, comprising:

• receiving, at a reception point of a radio system, line of sight and reflected radio waves;
• determining for each radio wave, by a deterministic estimation technique, whether or not an intensity of the main path of the radio wave to be evaluated is larger than a pre-decided threshold;
• estimating that a propagation characteristic of the radio wave has reached a minimum allowable level when the intensity of said main path is smaller than said threshold;
• estimating that it has not reached the minimum allowable level when the intensity of said main path is larger than said threshold;
• estimating an arrival status of the radio wave at said reception point by applying a first estimation technique of a radio wave propagation status for the reception point at which it is estimated that said minimum allowable level has been reached;
• and
• estimating an arrival status of the radio wave at said reception point by applying a second estimation technique of a radio wave propagation status, being a technique of which a precision is higher than that of said first estimation technique of the radio wave propagation status, for the reception point at which it is estimated that said minimum allowable level has not been reached,
• wherein said deterministic estimation technique is a ray tracing process that considers some but not all of reflection, transmission, diffraction, and irregular reflection of the radio wave in estimating the propagation characteristic of the radio wave, the propagation characteristic being associated with which of the reflection, the transmission, and the irregular reflection are considered by said deterministic estimation technique,
• wherein the ray tracing process is terminated when a propagation loss of the some but not all of the reflection, the transmission, the diffraction, and the reflection that are considered is less than an allowable propagation loss of a radio system, and said propagation characteristic includes at least one of an intensity of the radio waves received at the reception point, existence or not of an the line of sight radio wave, an intensity of a main path, an arrival angle, a radiation angle, and a delay spread.

A non-transitory computer readable storage medium storing a program for causing an information processing device to execute a process of:

• receiving, at a reception point of a radio system, line of sight and reflected radio waves:
• determining for each radio wave, by a deterministic estimation technique, whether or not an intensity of the main path of the radio wave to be evaluated is larger than a pre-decided threshold;
• estimating that a propagation characteristic of the radio wave has reached a minimum allowable level when the intensity of said main path is smaller than said threshold;
• estimating that it has not reached the minimum allowable level when the intensity of said main path is larger than said threshold;
• estimating an arrival status of the radio wave at said reception point by applying a first estimation technique of a radio wave propagation status for the reception point at which it is estimated that said minimum allowable level has been reached;
• and
• estimating an arrival status of the radio wave at said reception point by applying a second estimation technique of a radio wave propagation status, being a technique of which a precision is higher than that of said first estimation technique of the radio wave propagation status, for the reception point at which it is estimated that said minimum allowable level has not been reached,
• wherein said deterministic estimation technique is a ray tracing process that considers some but not all of reflection, transmission, diffraction, and irregular reflection of the radio wave in estimating the propagation characteristic of the radio wave, the propagation characteristic being associated with which of the reflection, the transmission, and the irregular reflection are considered by said deterministic estimation technique,
• wherein the ray tracing process is terminated when a propagation loss of the some but not all of the reflection, the transmission, the diffraction, and the reflection that are considered is less than an allowable propagation loss of a radio system, and said propagation characteristic includes at least one of an intensity of the radio waves received at the reception point, existence or not of an the line of sight radio wave, an intensity of a main path, an arrival angle, a radiation angle, and a delay spread.