Elements and technical features » History » Version 18

HAENNIG, Gerald, 12/15/2015 09:11 AM

1 5 GOMEZ, Ramon
h1. 2.1 Elements 
2 1 GOMEZ, Ramon
3 12 HAENNIG, Gerald
4 13 HAENNIG, Gerald
p=. !{width:700px}bloc_diagram.png!
5 14 HAENNIG, Gerald
Figure 1. Optical Link (source Miteq).
6 12 HAENNIG, Gerald
7 12 HAENNIG, Gerald
8 10 HAENNIG, Gerald
On optical link consists of :
9 17 HAENNIG, Gerald
* an optical transmitter ; it modulates input Radio Frequency (RF) signal onto the optical wavelength intensity. 
10 11 HAENNIG, Gerald
Optical intensity is varied either directly by varying Laser Diode current or indirectly through a Mach-Zehnder Modulator modulating a constant laser source.
11 10 HAENNIG, Gerald
* fiber optic : in general, monomode fiber optic is used to avoid dispersion especially for long link. Morever, wavelengths around 1300 nm are used as dispersion is minimum in this region.
12 10 HAENNIG, Gerald
* an optical receiver : it is based on a photodectector. It detects RF modulation on the optical wavelength and outputs the RF signal.
13 1 GOMEZ, Ramon
14 15 HAENNIG, Gerald
Such an optical link is referred to as Radio Over Fiber (RoF), as well.
15 14 HAENNIG, Gerald
16 10 HAENNIG, Gerald
The main parameters for an optical link are gain, bandwidth, Noise Figure (NF) and Spurious Free Dynamic Range (SFDR).   
17 1 GOMEZ, Ramon
18 1 GOMEZ, Ramon
MITEQ, Fiber optic products : https://www.miteq.com/docs/MITEQ_FiberOptic_c40.pdf
19 14 HAENNIG, Gerald
20 14 HAENNIG, Gerald
Main applications are 
21 16 HAENNIG, Gerald
* antenna remoting : 
22 16 HAENNIG, Gerald
for satellite broadcast TV, signal is received on the antenna on the roof but actually demodulated in the tuner in the living room.
23 18 HAENNIG, Gerald
for teleports, Radio-frequency signal transport through optical fibres from Antenna to the main building (containing Modulator/Demodulator, Network Equipments).
24 16 HAENNIG, Gerald
* signal distribution : 
25 16 HAENNIG, Gerald
for phased array radar application, it could be used to distribute the Local Oscillator to the different array elements.
26 16 HAENNIG, Gerald
for cable television (CATV : Community Antenna TeleVision) : to distribute the TV channels to the homes.
27 9 HAENNIG, Gerald
28 3 GOMEZ, Ramon
Earth stations are based on an indoor/outdoor unit architecture. In our system we will count on: 
29 1 GOMEZ, Ramon
30 8 GOMEZ, Ramon
* Outdoor: L-band reception antenna, the coaxial cable relying the antenna and the modulator transmitter (allows to convert from L-band to optic frequencies) and the 30m of Monomode FO. 
31 3 GOMEZ, Ramon
* Indoor: consists of the receiver L-band/optic demodulator and the coaxial cable to rely the demodulator with the TV. 
32 1 GOMEZ, Ramon
33 6 GOMEZ, Ramon
!schema.jpg!