A 2.4-GHz Wireless-Over-Fibre System Using Photonic Active Integrated Antennas (PhAIAs) and Lossless Matching Circuits

Abstract

Abstract-This paper demonstrates that very low cost wirelessover-fibre systems can be implemented without RF amplification by using lossless matching techniques. Single stub matching circuits were designed on low loss substrates and integrated with photodiode chips and results show that the link gain can be theoretically improved by more than 8 dB. A 2-port link gain model is developed using Agilent ADS which allows simple wideband modeling of such systems. Finally the system is tested using a "live" access point both with and without matching and results show that a maximum RF range of 4 m can be obtained at 2 Mbps data rate over 317 m of installed MMF with no RF amplification.Index Terms-Radio-over-fibre, vertical cavity surface emitting lasers (VCSELs), WLAN.

Wireless Hybrid Mode Locked Lasers for Next Generation Radio-Over-Fiber Systems

“…This approach is being explored at lower frequencies and is termed as photonic active integrated antenna [27], [28]. The advantage in this case is that in the mm-wave bands antennas become sufficiently small such that they could be integrated directly on the same semiconductor substrate as the laser.…”

Millimeter‐wave photonic active integrated antennas using hybrid mode‐locked lasers

“…The key feature of a PhAIA‐based system is the ability to achieve relatively wideband conjugate matching between the photonic device and the antenna with no, or at least very simple, matching networks. This results in maximum power transfer and can result in significant improvement in link gain over a narrow bandwidth [ 8, 9]. To achieve conjugate matching, it is required to have a detailed knowledge of the input impedance of the photonic device.…”

“…A number of authors [10, 11] have reported the use of impedance‐matching networks for MLLs to improve RF injection efficiency; however, no one has reported the actual input impedances for these sections. The technique used here is called de‐embedding [8, 9, 12]. The term refers to the ability of a vector network analyzer (VNA), used to measure the impedance, to move its reference plane, such that the phase shift introduced by connectors and microstrip transmission lines can be removed.…”

“…Forty giga hertz is being used here as a prototype frequency, because MLLs are currently not widely available at 60 GHz. This approach is also being explored at lower frequencies and is termed photonic active integrated antennas (PhAIAs) [8, 9]. The advantage here is that mm‐wave band antennas become sufficiently small such that they could be integrated directly on the same semiconductor substrate as the laser.…”

“…The advantage here is that mm‐wave band antennas become sufficiently small such that they could be integrated directly on the same semiconductor substrate as the laser. This has already been implemented for high‐speed PDs [9], but to the author's knowledge this has not been explored for lasers. Such fully monolithic MLL‐PhAIA chips could radically reduce the costs of RAU design for next generation RoF systems and could lead to the widespread adoption of this technology.…”