Wireless Communications From The Ground Up- An ...

Tiny wavelength (mm). Allows massive antenna arrays (32, 64, 128 elements) in a phone-sized device. Beamforming—electronically steering a focused beam of energy directly at your phone, ignoring reflections. The downside: a human hand blocks the signal.

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In wireless communications, we utilize specific portions of this spectrum—Radio Frequencies (RF) and Microwaves. The choice of frequency is the first critical decision in any system design.

Unlike most textbooks, this one: