The name is absent

THz transmitter
(fiber-coupled
PC antenna)

H

random
pattern

42cm

Figure 4.1 : The THz compressive imaging setup. An approximately collimated
beam from the THz transmitter illuminates an object mask and is partially (~50%)
transmitted through a random pattern of opaque pixels. The random patterns, the
focusing lens and the receiver are placed in order to most efficiently focus the THz
beam onto the receiver antenna. One complete time-domain waveform is collected
for each random pattern.

pixels in the image, i.e., M < N², and can still reconstruct the object perfectly,
through an optimization procedure as described in references [8,9]. The THz Fourier
imaging scheme using CS and phase retrieval in Chapter 3 uses a random subset of
the Fourier basis as rows of Φ. Here, the single-pixel imaging method chooses a set of
vectors, whose entries are randomly picked to be 1 or 0 with equal probability, as rows
of Φ [60]. In other words, for each row in Φ, only a random subset (approximately
half) of the pixels are set to unity (100% transmission), while the remainder are set
to zero (no transmission). Thus, the terahertz beam traveling from the object to the
detector is filtered by randomly blocking a subset of the spatial wave front.

4.2 Imaging experiment

Figure 4.1 illustrates the imaging setup, which consists of a THz transmitter/receiver
pair (fiber-coupled photoconductive antenna), a planar screen with a random pattern

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