Popis: |
The last chapter was a description of the free wave idea. In whatever context a free wave field is encountered, it will always have certain general characteristics: in particular, the complex cross-spatial density (CCSD) taken between two observation points in the field may always be expressed as a weighted integral of uncorrelated plane wave contributions. The plane wave weighting function occurring in this integral completely characterises the field, and its interpretation was outlined in Chapter Two. |