  The utilization of millimeter wave frequency bands is expected to become
prevalent in the following communication systems. However, generating and
transmitting communication signals over these frequencies is not as
straightforward as in sub-6 GHz frequencies due to complex transceiver
structures. As an alternative to conventional transmitter architectures, this
paper investigates the implementation of time-modulated arrays to effectively
modulate and transmit high-quality communication signals at millimeter wave
frequencies. By exploiting the array structures and analog beamformers, which
are the fundamental components of millimeter wave transmitters, secure and
low-cost transmission can be achieved. Though, harmonics of theoretically
infinite bandwidth arise as a fundamental problem in this approach. Thus, this
paper presents a frequency analysis tool for the time-modulated arrays with
hardware impairments and shows how controlling the sampling period can reduce
the harmonics. Furthermore, the derived results are experimentally verified at
25 GHz with two important remarks. First, the phase error of received signals
can be reduced by 32% using the proposed architecture. Second, the harmonics
can be significantly suppressed by the correct choice of sampling period for
the given hardware.
