Unwrapping algorithm for least-squares phase recovery from the modulo 2π bispectrum phase

One algorithm proposed for recovering an object’s Fourier phase from the phase of its bispectrum is the least-squares solution of the overdetermined system of equations that relate the Fourier and bispectrum phases. Although the least-squares technique is robust with respect to noise, it fails when the bispectrum phase is known only modulo 2π. A technique is presented for unwrapping the modulo 2π bispectrum; one can then obtain an accurate least-squares phase solution. Simulations that demonstrate the technique and test sensitivity to noise are given.