mathematical formula that enables a sonar's performance to be evaluated Note 1 to entry: The equation that applies to sonars exists in a number of forms, because the evaluation is of a one-way transmission level, a two-way echo level or a bistatic echo level. Note 2 to entry: The terms of the equation that applies to sonars are generally logarithmic and expressed in units of decibels. Consequently, the sonar equation consists of an arithmetic sum of terms. |