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Low-noise block downconverter
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== Common LNBs == === [[C band (IEEE)|C-band]] LNB === Here is an example of a North American [[C band (IEEE)|C-band]] LNB: * Local oscillator: 5.15 GHz * Frequency: 3.40β4.20 GHz * [[Noise temperature]]: 25β100 [[kelvin]]s (uses kelvin ratings as opposed to dB rating). * Polarization: Linear {| class="wikitable" |- ! rowspan=2 | Supply <br/>voltage ! colspan=2 | Block ! rowspan=2 | Local oscillator <br/>frequency ! rowspan=2 | Intermediate <br/>freq. range |- ! Polarization ! Frequency band |- | 13 V | Vertical | 3.40β4.20 GHz | 5.15 GHz | 950β1,750 MHz |- | 18 V | Horizontal | 3.40β4.20 GHz | 5.15 GHz | 950β1,750 MHz |} === [[Ku band|K{{sub|u}}-band]] LNB === [[Image:KuBAND-LNB-0A0B.jpg|220px|thumb|K<sub>u</sub>-band LNB with both sides uncovered]] ==== Standard North America K<sub>u</sub> band LNB ==== Here is an example of a standard linear LNB: * Local oscillator: 10.75 GHz * Frequency: 11.70β12.20 GHz * Noise figure: 1 dB typical * Polarization: Linear {| class="wikitable" |- ! rowspan=2 | Supply <br />voltage ! colspan=2 | Block ! rowspan=2 | Local oscillator <br />frequency ! rowspan=2 | Intermediate <br />freq. range |- ! Polarization ! Frequency band |- | 13 V | Vertical | 11.70β12.20 GHz | 10.75 GHz | 950β1,450 MHz |- | 18 V | Horizontal | 11.70β12.20 GHz | 10.75 GHz | 950β1,450 MHz |} ==== Universal LNB ("Astra" LNB) ==== [[Image:astra lnb.jpg|thumb|left|120px|[[Astra (satellite)|Astra]]-type LNBF]] In Europe, as [[SES (company)|SES]] launched more [[Astra (satellite)|Astra]] satellites to the [[Astra 19.2Β°E|19.2Β°E]] orbital position in the 1990s, the range of [[downlink]] frequencies used in the [[Fixed satellite services|FSS]] band (10.70β11.70 GHz) grew beyond that catered for by the standard LNBs and receivers of the time. Reception of signals from [[Astra 1D]] required an extension of receivers' IF tuning range from 950β1,950 MHz to 950β2,150 MHz and a change of LNBs' local oscillator frequency from the usual 10 GHz to 9.75 GHz (so-called ''enhanced'' LNBs). The launch of [[Astra 1E]] and subsequent satellites saw the first use by Astra of the [[BSS band]] of frequencies (11.70β12.75 GHz) for new digital services and required the introduction of an LNB that would receive the whole frequency range 10.70β12.75 GHz, the ''universal'' LNB. A universal LNB has a switchable local oscillator frequency of 9.75/10.60 GHz to provide two modes of operation: low band reception (10.70β11.70 GHz) and high band reception (11.70β12.75 GHz). The local oscillator frequency is switched in response to a 22 kHz signal superimposed on the supply voltage from the connected receiver. Along with the supply voltage level used to switch between polarizations, this enables a universal LNB to receive both polarizations (vertical and horizontal) and the full range of frequencies in the satellite {{Ku band}} under the control of the receiver, in four sub-bands:<ref>{{cite web|url=https://pro.ses-astra.com/resources/dealers/dish_inst_broch1.pdf|title=Professional Dish Installation|publisher=ASTRA (GB) Limited|date=March 2005|page=7|url-status=dead|archive-url=https://web.archive.org/web/20110716043156/https://pro.ses-astra.com/resources/dealers/dish_inst_broch1.pdf|archive-date=2011-07-16}}</ref> Here is an example of a universal LNB used in Europe: * Noise figure: 0.2 dB typical * Polarization: Linear {| class="wikitable" |- ! colspan=2 | Supply ! colspan=2 | Block ! rowspan=2 | Local oscillator <br/>frequency ! rowspan=2 | Intermediate <br/>freq. range |- ! Voltage ! Tone ! Polarization ! Frequency band |- | 13 V | 0 kHz | Vertical | 10.70β11.70 GHz, low | 9.75 GHz | 950β1,950 MHz |- | 18 V | 0 kHz | Horizontal | 10.70β11.70 GHz, low | 9.75 GHz | 950β1,950 MHz |- | 13 V | 22 kHz | Vertical | 11.70β12.75 GHz, high | 10.60 GHz | 1,100β2,150 MHz |- | 18 V | 22 kHz | Horizontal | 11.70β12.75 GHz, high | 10.60 GHz | 1,100β2,150 MHz |} ==== North America DBS LNB ==== Here is an example of an LNB used for [[Direct broadcast satellite|DBS]]: * Local oscillator: 11.25 GHz * Frequency: 12.20β12.70 GHz * Noise figure: 0.7 dB * Polarization: Circular {| class="wikitable" |- ! rowspan=2 | Supply <br/>voltage ! colspan=2 | Block ! rowspan=2 | Local oscillator <br />frequency ! rowspan=2 | Intermediate <br />freq. range |- ! Polarization ! Frequency band |- | 13 V | Right-hand | 12.20β12.70 GHz | 11.25 GHz | 950β1,450 MHz |- | 18 V | Left-hand | 12.20β12.70 GHz | 11.25 GHz | 950β1,450 MHz |} === [[Ka band|K{{sub|a}} band]] LNB === Here are examples of [[Ka band|K{{sub|a}} band]] LNBs: {| class="wikitable" |- ! rowspan=2 | Supply <br/>voltage ! colspan=2 | Block ! rowspan=2 | Local oscillator <br />frequency ! rowspan=2 | Intermediate <br />freq. range |- ! Polarization ! Frequency band |- | 13 V | Right-hand | 20.2β21.2 GHz | 19.25 GHz | 950β1,950 MHz |- | 18 V | Left-hand | 20.2β21.2 GHz | 19.25 GHz | 950β1,950 MHz |- | 13 V | Right-hand | 21.2β22.2 GHz | 20.25 GHz | 950β1,950 MHz |- | 18 V | Left-hand | 21.2β22.2 GHz | 20.25 GHz | 950β1,950 MHz |} Here is an example of a [[Norsat]] [[Ka band|K{{sub|a}} band]] LNB: {| class="wikitable" |- ! rowspan=2 | Supply <br/>voltage ! colspan=2 | Block ! rowspan=2 | Local oscillator <br />frequency ! rowspan=2 | Intermediate <br />freq. range |- ! Polarization ! Frequency band |- | 13 V | Right-hand | 18.2β19.2 GHz | 17.25 GHz | 950β1,950 MHz |- | 18 V | Left-hand | 18.2β19.2 GHz | 17.25 GHz | 950β1,950 MHz |} === [[S band]] LNB === [[Image:S-Band_LNB_Bottom_View.jpg|220px|thumb|S-band LNB with written local oscillator frequency]] Here is an example of an [[S band]] LNB: * Local oscillator: 1.57 GHz * Frequency: 2.52-2.67 GHz * [[Noise temperature]]: Maximum of 50 [[kelvin]]s (uses kelvin ratings as opposed to dB rating) * Polarization: Linear {| class="wikitable" |- ! rowspan=2 | Supply <br/>voltage ! colspan=2 | Block ! rowspan=2 | Local oscillator <br/>frequency ! rowspan=2 | Intermediate <br/>freq. range |- ! Polarization ! Frequency band |- | 13 V | Vertical | 2.52-2.67 GHz | 1.57 GHz | 950β1,100 MHz |- | 18 V | Horizontal | 2.52-2.67 GHz | 1.57 GHz | 950β1,100 MHz |} This frequency range of LNB is quite rare as the only [[Satellite television|direct broadcast]] satellites that work with the S-band frequency are [[IndoStar-1]] and [[SES-7|IndoStar-2]], both utilized by Indonesian direct-to-home provider [[MNC Vision]]. S-band was chosen for these satellites because its frequencies efficiently penetrate the atmosphere and provide high-quality transmissions to small-diameter 80 cm antennas in regions that experience heavy rainfall such as Indonesia. A similar Ku- or C-band reception performance requires greater transmission power or much larger dish to penetrate the moist atmosphere.
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