This thread is complete guide to lnb or Low noise block downconverter and conjointly we have a tendency to explained its sorts. truly this device is expounded to television system users and lnb satellite setup. it's forever situated on the front of satellite dish. operating method of the device is expounded to satellite signals and changing them into lower bands. It receive the signals from satellite and that square measure low level microwave therefore it coverts them into low level frequency bands conjointly amplify them and so transmit them to the receiving system that is found indoor. the ability is shipped by receiver to the current device for operating. Power is shipped by mistreatment same cable that's wont to send signals to receivers by this we have a tendency to don’t would like a separate cable for power.
The term low noise term utilized in name is expounded to quality of transistors situated in device that works as 1st stage input amplifiers. The unit during which quality of lnb is measured in Noise temperature. different alternatives square measure noise issue or noise figure. They each may be reborn to noise temperature. therefore however the standard is measured? Answer is lower the noise temperature higher is that the quality and better the noise temperature lower is that the quality of device. AN example} if an lnb device have the noise temperature 100K and second have the 200K than 1st is double sensible from second in quality. Devices with c band square measure higher than Hindu deity band owing to lower noise temperature. therefore I counsel c band devices for higher results.
The block term utilized in name is expounded to conversion of frequencies from microwave to lower block or ranges that square measure received from satellite. The vary of satellite broadcast is from four to twelve to twenty one gigahertz.
The term low noise term utilized in name is expounded to quality of transistors situated in device that works as 1st stage input amplifiers. The unit during which quality of lnb is measured in Noise temperature. different alternatives square measure noise issue or noise figure. They each may be reborn to noise temperature. therefore however the standard is measured? Answer is lower the noise temperature higher is that the quality and better the noise temperature lower is that the quality of device. AN example} if an lnb device have the noise temperature 100K and second have the 200K than 1st is double sensible from second in quality. Devices with c band square measure higher than Hindu deity band owing to lower noise temperature. therefore I counsel c band devices for higher results.
The block term utilized in name is expounded to conversion of frequencies from microwave to lower block or ranges that square measure received from satellite. The vary of satellite broadcast is from four to twelve to twenty one gigahertz.
Polarization:
Polarization could be a method through that they will transmit a lot of TV channels mistreatment minimum given frequencies. then again this method needed special receiving instrumentation for receiving signals that then filter the incoming signals aboard of polarization.
The probe within the Lnb devices solely receive those signals that match the plane of probe. therefore for increasing the strength and minimizing the unwanted signals probe is about or aligned with polarization of satellite signals. this will be set by adjusting the LBN’s skew and rotating it on wavelength axis. Some times for higher results polarizer is slot in front of LBN’s mouth however these polarizers square measure seldom used currently a days.
The probe within the Lnb devices solely receive those signals that match the plane of probe. therefore for increasing the strength and minimizing the unwanted signals probe is about or aligned with polarization of satellite signals. this will be set by adjusting the LBN’s skew and rotating it on wavelength axis. Some times for higher results polarizer is slot in front of LBN’s mouth however these polarizers square measure seldom used currently a days.
Types of lnb device:
C band LNB:
Here is example of a C band LNB device and properties square measure following:
- 5.15 gigahertz of heterodyne oscillator.
- Frequency vary is from three.40 to 4.20 GHz.
- Noise figure or noise temperature is from twenty five to a hundred kelvins.
- Linear Polarization is employed during this device.
Ku band LNB:
It is a regular North America kurchatovium band LNB that have following specifications.
- Local generator of ten.75 gigahertz band.
- Frequency ranges from eleven.70 to 12.20 GHz.
- Noise figure is one decibel generally.
- Polarization utilized in device is Linear.
Dual band lnb device:
Ku band LNBs largely use 2 variety of various heterodyne oscillator frequencies like nine.75 gigahertz to ten.6 gigahertz conjointly having the upper frequency possibility may be elect mistreatment twenty two kilocycle per second tone by injecting into cable. These devices will wont to receive high bands of ten.7 to 11.7 gigahertz whereas mistreatment lower bands of nine.7 gigahertz LO frequency conjointly higher band of eleven.7 to 12.7 gigahertz may be received mistreatment ten.60 gigahertz LO frequency. a number of kurchatovium band lnb devices will have four heterodyne oscillator frequencies.
Quattro lnb:
This is a special variety of LNB planned to be used in an exceedingly common or shared dish setup to hold signals to any range of TV tuners. A quattro lnb has associate degree only 1 feed horn and 4 outputs, every one of them stream only one of the kurchatovium sub bands. though a quattro typically appearance the same as a quad lnb, however it can not be connected to receivers directly.