How many pixels does the profile of the object span?

Suppose that a slice has been selected through a 5 × 5 × 5 cm cube. We wish to produce a projection of this slice with the application of a readout gradient. The pulse sequence in Figure P13.4 is used to produce the profile

Suppose the gradient strength is G = 1 G/cm and N = 256 sample points are taken in the total sampling time NT = 10 ms (recall that T is the time between sampling points in the readout direction).

(a) What is the spatial extent (i.e., the FOV) of the profile? What is the bandwidth of the received signal?

(b) How many pixels does the profile of the object span?

(c) Suppose we set G = 0.5 G/cm, N = 256, and NT = 20 ms. How does this affect (a) and (b)? (d) Repeat (a) to (c) for the pulse sequence shown in Figure P13.5.

Figure P13.5 See Problem 13.9(d).

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