Using optical fibre for the distribution of microwave signals has several benefits compared to using electrical cables. Optical fibre has low loss and frequency-independent attenuation. It is also insensitive to electromagnetic interference, low in weight, small in size and low in cost.
To meet the future demand generated by the constantly increasing number of devices that are wireless connected, and at the same time maintain full mobility and high data rates, new higher frequencies must be brought into use, as the frequency space is becoming congested.
In a new PhD thesis by Andreas Wiberg at the Photonics Laboratory at Chalmers, research is presented which deals with optical generation, modulation and distribution of signals in micro- and millimetre-wave applications. The results obtained include demonstrations of transportation of 40 GHz signals over 44 km of optical fibre modulated with 2.5 Gbit/s data, transmitted through a wireless link in a laboratory environment.
"Fibre optic solutions are particularly beneficial at high frequencies and over longer distances. Combining photonic technology and microwave applications opens up new, interesting possibilities and technical solutions," says Andreas Wiberg.
In order to also maintain sufficient coverage at high frequencies, new wireless systems with distributed antennas are required for both indoor and outdoor solutions. These antennas can be managed from a central location and with centralised control; dynamic channel allocation is possible in order to follow fluctuations in traffic load and maintain good wireless coverage.
Researchers at the Department of Microtechnology and Nanoscience at Chalmers University of Technology have investigated the possibility of using fibre optic technology to generate and distribute microwave signals for future networks with wireless Gigabit/s data rates, so-called Radio-over-Fibre.
The work by Andreas Wiberg also presents details of how several frequencies and/or frequency bands can be sent in parallel through a microwave photonic system in which optical filtering is used to separate the different frequencies. It is also shown that optical techniques could be used to generate high-frequency harmonics from electrically generated signals.
The use of photonic technology in microwave applications is referred to as Microwave Photonics and has many applications apart from communication. Microwave Photonics can also be used in analogue applications, such as reference signal generation and distribution of these signals to antenna arrays. Examples of such applications could be phase-steered radar antennas or large antenna arrays for radio astronomy.
Andreas Wiberg's thesis "Generation, Modulation, and Detection of Signals in Microwave Photonic Systems" will be defended in public on March 14, 2008.Time: 10 am
An abstract of the thesis is available in the Chalmers publication database, www.chalmers.seFor further information, please contact:
Sofie Hebrand | idw
New manufacturing process for SiC power devices opens market to more competition
14.09.2017 | North Carolina State University
Quick, Precise, but not Cold
17.05.2017 | Fraunhofer-Institut für Lasertechnik ILT
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research