| 摘 要： | An exact sound power emission formula of a simple source in a reverberation chamber is derived fromnormal mode theory as a function of its position in the room,and important properties of the emission arefound from simple analyses.For example,the average emission of the source in the room is not equal to thefree space emission but greater,on the contrary to the common notion.A smooth statistical formula is alsoderived for the variation of average sound power in an axial direction,which holds even at low frequency atwhich the wave length approaches the mean free path in the room.The sound power is found to havenumerous peaks in the room forming a three-dimensional lattice structure with high power barriers aroundthe boundary walls.The space factor in an axial direction is essentially exact,but the general formula of poweremission formed with the product of space factors in three axial directions might have some error.Numericalexamples are presented to check this.The variability of sound power emission in
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