Cyclic additional optical true time delay for microwave beam steering with spectral filtering

Area of Science:

• Optoelectronics
• Microwave Engineering
• Wireless Communication

Background:

• Optical true time delay (OTTD) offers broadband, low-loss, and compact solutions for microwave beam steering (MBS).
• Existing OTTD methods face challenges in achieving simultaneous spectral and spatial filtering.

Purpose of the Study:

• To propose and demonstrate a novel OTTD approach, cyclic additional optical true time delay (CAO-TTD).
• To enable tunable spectral and spatial filtering for broadband MBS applications.

Main Methods:

• Implementing CAO-TTD by introducing additional integer delays to the microwave carrier frequency.
• Utilizing the CAO-TTD concept to develop a broadband MBS scheme.
• Conducting experimental validation of the proposed scheme.

Main Results:

• The CAO-TTD approach successfully achieves spectral filtering without disrupting spatial filtering (beam steering).
• The proposed broadband MBS scheme allows independent tuning of both spectral and spatial filtering.
• Experimental results align closely with theoretical predictions.

Conclusions:

• CAO-TTD is a viable and effective method for advanced microwave beam steering.
• The proposed scheme enhances capabilities for high-capacity wireless communication systems.
• This work advances the integration of optical true time delay in microwave applications.