An Optically Controlled Coplanar Waveguide Millimeter-Wave Switch

Abstract

This paper demonstrates an optically controlled Co-Planar Waveguide (CPW) switch operating in the millimetre wave region. Full wave electromagnetic analysis used a multi-layer model to simulate the photoinduced plasmas and good agreement between measured and simulated results has been achieved. The insertion loss is less than 4dB and isolation is greater than 15dB from 32GHz-50GHz. This approach requires the use of 175mW of optical power at a wavelength 980nm, but it removes the need for bandwidth limiting electrical bias networks. Index Terms-Optically induced plasmas (OIP), Co-Planar Waveguide (CPW), millimeter wave (mmW), optical switch

Optically controlled millimetre‐wave switch with stepped‐impedance lines

“…The switches in [2,4,5,8] are not capable of working above 6 GHz. Compared to works in [9,10] which can operate at higher frequencies, our proposed switch is the only one which covers the entire K u -band, K-band and upper 5G experimental band, with a particularly good RF performance (isolation ≥21.9 dB, insertion loss ≤ 1.1 dB, off-state RL ≥ 16.5 dB and on-state RL ≥ 13.8 dB) in the K-band. Moreover, our proposed switch is the only one which combines simple laser-etching fabrication and the use of an LED as the light source which is much cheaper and smaller than a fibre-coupled laser over 6 GHz.…”

“…In the higher portion of the microwave band, a CPW switch in [9] obtained an average 40 dB isolation on a high resistivity (HR) silicon substrate from 2.3 to 25 GHz with a 65 mW fibre-coupled laser. We recently also reported a grounded CPW (GCPW) millimetre-wave switch [10] based on a glass substrate and silicon superstrate which obtained isolation better than 15 dB from 32 to 50 GHz using a 175 mW fibre-coupled laser. However, the illuminated areas in [9][10] were confined to within the dimensions of 1 × 1 mm 2 which are difficult to achieve using compact and lowcost LEDs.…”

“…We recently also reported a grounded CPW (GCPW) millimetre-wave switch [10] based on a glass substrate and silicon superstrate which obtained isolation better than 15 dB from 32 to 50 GHz using a 175 mW fibre-coupled laser. However, the illuminated areas in [9][10] were confined to within the dimensions of 1 × 1 mm 2 which are difficult to achieve using compact and lowcost LEDs. Moreover, Flemish and Haupt [8], Ali et al [9], and Pang et al [10] required costly and time-consuming optical lithographical fabrication and thus cannot be integrated with typical microwave printed circuit boards (PCBs) directly.…”

“…However, the illuminated areas in [9][10] were confined to within the dimensions of 1 × 1 mm 2 which are difficult to achieve using compact and lowcost LEDs. Moreover, Flemish and Haupt [8], Ali et al [9], and Pang et al [10] required costly and time-consuming optical lithographical fabrication and thus cannot be integrated with typical microwave printed circuit boards (PCBs) directly. In addition, none of [2][3][4][5][6][7][8][9][10] are completely absorptive (both on-state and off-state return loss (RL) ≥ 10 dB) within their operating frequency bands which may cause problems in many microwave systems such as switched antenna beamforming systems.…”

Photo-Controlled Quantum Capacitors in Gated Graphene-Insulator-Graphene for Terahertz Frequency and Phase Modulations

“…For on-chip communication, photo control has many advantages over electrical control, such as response sensitivity, no parasitic parameters and greatly modulated frequency [4]. These properties mean optical signals can achieve higher bandwidth than electrical signals, which are suitable for THz applications [5], [6]. Thus, it is worthwhile to research THz communication devices based on optical carrier.…”