A medical imaging system has a Gaussian PSF given by h(x, y) = 1 270 e-22u2...

  

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A medical imaging system has a Gaussian PSF given by h(x, y) = 1 270² e-2πσ2u2 MTF(u) = e e x²+y² 20² (e) Sketch the MTF as a function of frequency for the two cases where o = 1 and σ = 3. For each sketch, indicate the frequency values where the MTF is equal to 0.1, 0.5 and 1. (2 marks) (f) What is the FWHM associated with the system for the two cases where σ = 1 and σ = 3. (3 marks) (g) In which case does the system have a higher spatial resolution, σ = 1 or σ = 3? Why? (1 mark) (h) What are the spatial frequencies (u and v) for an input signal f(x, y) = cos(2x) + cos (ny)? Calculate the MTF values at these frequencies for σ = 1. Calculate the percentage change in modulation caused by this system (i.e. 100 x (1 - MTF(u))% and 100 x (1 - MTF (v))%). (3 marks) A medical imaging system has a Gaussian PSF given by h(x, y) = 1 270² e-2πσ2u2 MTF(u) = e e x²+y² 20² (e) Sketch the MTF as a function of frequency for the two cases where o = 1 and σ = 3. For each sketch, indicate the frequency values where the MTF is equal to 0.1, 0.5 and 1. (2 marks) (f) What is the FWHM associated with the system for the two cases where σ = 1 and σ = 3. (3 marks) (g) In which case does the system have a higher spatial resolution, σ = 1 or σ = 3? Why? (1 mark) (h) What are the spatial frequencies (u and v) for an input signal f(x, y) = cos(2x) + cos (ny)? Calculate the MTF values at these frequencies for σ = 1. Calculate the percentage change in modulation caused by this system (i.e. 100 x (1 - MTF(u))% and 100 x (1 - MTF (v))%). (3 marks)

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e The MTF for a Gaussian PSF is given by MTFu e22u2 where u is the spatial frequency and is th... View the full answer