Electroabsorption Transceiver Research Articles

Fabrication of an electro-absorption transceiver with a monolithically integrated optical amplifier for fiber transmission of 40–60 GHz radio signals

We report on the fabrication of a monolithically integrated semiconductor optical amplifier (SOA) and a reflective electro-absorption transceiver (EAT) for 40–60 GHz radio-over-fiber applications. The EAT can either function as a transmitter (reflective modulator) or as a receiver (photodetector) depending on operation mode. The SOA and the EAT sections are based on different InGaAsP multiple quantum-well active layers connected by a butt joint. Benzocyclobutene is used to reduce the capacitance beside the ridge mesa. Devices are designed to have a peaked response at the operating frequency through the design of microwave waveguides on top of the devices. The packaged device exhibits at 0.1 mW optical input power an amplified DC responsivity of 18.5 mA mW−1 and a modulation efficiency of 0.67 mW V−1. The estimated radio frequency loss at 40 GHz of an optical link consisting of two SOA–EAT devices was 23 dB using an unmodulated optical input carrier to the transmitter of 0.94 mW.

Colorless gigabit WDM-PON link using injection locking and electro-absorption transceiver

In this paper, a novel colorless wavelength division multiplexing-passive optical network (WDM-PON) system using injection locking and electro-absorption transceiver (EAT) is proposed and demonstrated experimentally. This system has advantages, high data transmission, small downlink signal effect to uplink signal and less polarization sensitivity, compared to the system using reflective semiconductor optical amplifier (RSOA). Downlink signal modulates the right side carrier of the double side band signal by using injection locking. EAT functions as both photo detector in downlink signal and modulator for uplink signal, simultaneously. A possible cross absorption modulation effect from the EAT is analyzed experimentally. Bidirectional transmission of 1.25 Gbps and 622 Mbps for downlink and uplink, respectively, were verified through 23 km standard single mode fiber (SSMF).

Visible light wireless transmission based on optical access network using white light‐emitting diode and electroabsorption transceiver

AbstractWe propose the visible light communication (VLC) system based on optical access network using light‐emitting diode (LED) and electroabsorption transceiver (EAT).The EAT based on electroabsorption modulator is used as an optical network unit in order to be connected with VLC link based on white LED and photodiode (PD). The proposed architecture is demonstrated experimentally, and its performance is verified through the experimental investigation of quality factor and eye pattern of 5 Mbps baseband data. The variation of performance is shown depending on both the existence of the ambient light and the distance between the LED array and PD. A total of 5 Mbps downlink and uplink transmission is verified through 23.2‐km single‐mode fiber and wireless channel experimentally. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:790–793, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25045

Low-Detuning Operation of Electroabsorption Modulator as a Zero-Bias Optical Transceiver for Picocell Radio-Over-Fiber Applications

We examined the effect of low detuning when the electroabsorption modulator was operated as an optical transceiver for passive picocell applications. By changing the light wavelength from 1550 to 1536 nm for low detuning between the light and the exciton-peak wavelengths, we were able to operate this electroabsorption transceiver (EAT) at zero bias with the performance similar to what could be obtained under external bias. Frequency response of the EAT was also examined to show very little degradation with the zero-bias operation.

Coverage Range and Cost Comparison of Remote Antenna Unit Designs for In-building Radio over Fiber Technology

Future communication needs to be ubiquitous, broadband, convergent, and seamless. Radio over fiber (RoF) technology is one of the most important enabler in access network for the technologies. Adoption of RoF faces bottleneck in optoelectronics, that they are still expensive, high power consumption, and limited in bandwidth. To solve the problem, transceiver in remote antenna unit (RAU) is developed, i.e. electroabsorption transceiver (EAT) and asymmetric FabryPerot modulator (AFPM). This paper compares their coverage range and cost in providing WCDMA and WLAN services. Needed gain of RF amplifier for supporting picocell is also discussed.

WCDMA radio-over-fibre transmission experiment using electro-absorption transceiver

An electro-absorption transceiver has been evaluated for use as a remote antenna unit in a WCDMA in-building distributed antenna system. The experiment showed penalty-free transmission over a wide range of input and output RF powers. The ACLR limited the downlink output power to less than −28 dBm.

60-GHz-band full-duplex radio-on-fiber system using two-RF-port electroabsorption transceiver

A full-duplex radio-on-fiber system using a newly developed 60-GHz-band optical transceiver is investigated. We fabricated a 60-GHz-band two-radio-frequency (RF)-port electroabsorption transceiver (EAT) module, which is the first developed 60-GHz-band optical transceiver in the world. The EAT module has individual RF input and output ports, each with impedance-matching circuits that enhance modulation and detection efficiencies near 60 GHz. A radio-on-fiber testbed adopting the EAT has an advantage that a base station becomes the simplest configuration, which basically consists of only the 60-GHz-band EAT. Using the radio-on-fiber testbed, the simultaneous transmission of 59.6-GHz (downlink) and 60.0-GHz (uplink) signals with data of 156 Mb/s is experimentally demonstrated.

An approach to single optical component antenna base stations for broad-band millimeter-wave fiber-radio access systems

To realize a cost-effective and practical antenna base station (BS) for 60-GHz-band millimeter-wave fiber-radio access systems, an approach to a single optical component BS is presented in this paper. The external modulation technique will allow to replace the pair of a photodetector (PD) and a laser diode with an external modulator at the BS by an optical transceiver. Two system architectures using different types of optical transceivers are studied in detail: one employs an electroabsorption transceiver (EAT), and the other employs an electroabsorption transceiver/mixer (EATX). The EAT serves simultaneously as a PD and an external light modulator in 60-GHz-band millimeter-wave region. The EATX furthermore acts as an IF-to-RF upconverter and an RF-to-IF downconverter. It is shown that both system architectures have good prospects to realize cost-effective fiber-radio access systems.

Full-duplex 60 GHz fibre optic transmission

A full-duplex millimetre-wave fibre optic system based on a high-speed electroabsorption transceiver (EAT) is proposed. Full-duplex fibre optic transmission of broadband (155.52 Mbit/s) 60 GHz-band millimetre-wave signals is experimentally demonstrated. Excellent transmission quality (BER < 10-9) is achieved for uplink and downlink transmission, simultaneously.