**Abstract**

In this chapter, we review the worldwide progress referred to designing optical beamforming networks intended to the next-generation ultra-wideband millimeter-wave phased array antennas for incoming fifth-generation wireless systems, which in recent years is under the close attention of worldwide communication community. Following the tendency, we study in detail the design concepts below true-time-delay photonics beamforming networks based on switchable or continuously tunable control. Guided by them, we highlight our NI AWRDE CADbased simulation experiments in the frequency range of 57–76 GHz on design of two 16-channel photonics beamforming networks using true-time-delay approach. In the first scheme of the known configuration, each channel includes laser, optical modulator, and 5-bit binary switchable chain of optical delay lines. The second scheme has an optimized configuration based on only 3-bit binary switchable chain of optical delay lines in each channel, all of which are driven by four lasers with wavelength division multiplexing and a common optical modulator. In the result, the novel structural and cost-efficient configuration of microwave-photonics beamforming network combining wavelength division multiplexing and true-time-delay techniques is proposed and investigated.

**Keywords:** ultra-wideband millimeter-wave antenna array, computer aided design and optimization, photonics-based beamforming network
